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University  of  California  •  Berkeley 


THE 

ANALYST; 

O  R,    A 

DISCOURSE 

AddrcfTcd  to  an 

Infidel  Mathematician. 

WHEREIN 

It  IS  examined  whether  the  Objedl,  Princi- 
ples, and  Inferences  of  the  modern  Analy- 
fis  are  more  diftindly  conceived,  or  more 
evidently  deduced,than  Religious  Myfteries 
and  Points  of  Faith. 


By  the  A  u  T  H  o  R  of  ne  Minute  Phllofipher. 


Firjl  cajl  out  the  beam  out  of  thine  own  Eye ;  and  then 
Jhalt  thou  fee  clearly  to  cajl  out  the  mote  out  of  thy  bro- 
ther's eye,  S.  Matt.  c.  vii.  v.  5". 


LO  N  D  ON: 
Printed  for  J.  Tonson  in  the  Strand,  17J4. 


(P 


.1^'' 


.#■ 


THE 

CONTENTS. 

SEC  T.  I.  Mathematipiam  frefumed  to 
be  the  great  Mafier^  cf  Reafon,  Hence 
an  nmche  Reference  ^o  their  decifions 
where  they  have  no  right  to.dedde.  This 
.one  Cmfe  fif  .Infidelity. 

II.  Their  Prirwiplejs  and  Methods  to  be  exa-^ 
mined  with  the  fame  Jreedom^  which 
they  -ajfume  witi  regard  to  the  Principles 
and  Myjleries  of  Religion,  In  what  Senje 
and  how  far  Geometry  is  to  be  allowed  an 
Jfnproipement  of  :the  Mind. 

III.  Fltixions'the  •greatObjedi  and  Employment 
of  the  profound  Geometricians  in  the  pre- 

feut  ^e.   What  tkeje  pluxioiu  are. 

IV".  "Moments  or  nafoent  Increments  cfflowirig 
^antities  difficiilt  4o  conceive.  Fluxions 
<f  different  -Orders.  Second  and  third 
Fluxions  obfcure  Myjleries. 

A  2  V.  Differ 

4340iG 


The    CONTENTS. 

V.  Differences^  i.  e.  Increments  or  Decre-^ 
ments  infinitely  fmall^  ufed  by  foreign  Ma^ 
thematicians  infiead  of  Fluxions  or  Velo^ 
cities  of  nafcent  and  evanefcent  Incre-- 
ments. 

VI.  Differences  of  various  Orders^  i.  e.  ^an-- 
tiiies  infinitely  lefs  than  ^antities  infi* 
nitely  little ;  and  infinitefimal  Farts,  of 
infinitefimals  of  infinitefimalsy  ix.c,  without 
end  or  limit, 

VII.  Myfieries  in  faith  unjufily  objeSiedagainJi 
by  thofe  who  admit  them  in  Science. 

VIII.  Modern  Analyfis  fuppofed  by  themfelves 
-  to  extend  their  views  even  beyond  infinity  : 

Deluded  by  their  own  Species  or  Symbols. 

IX.  Method  for  finding  the  Fluxion  of  a  ReSi-- 
'ungle.  of  two  indeterminate  ^antities^ 
.Jhewed  to  be  illegitimate  andfalfe. 

X.  Implicit  Deference  of  Mathematicalmen 

for  the  great  Author  of  Fli^xions.  7'heir 
eamefinefs  rather  to  go  onfafi  and  far ^ 
than  tofet  out  warily  and  fee  their  way 
difiin^lly, 

XL  Momen^ 


TSe    CONTENTS. 

XI.  Momenfums  difficult  io  comprehend,  Nd 
mddk  ^antity  to  be  admitted  between 
a  finite  ^antifj  and  nothings  'without 
admitting  Infiniiefimals. 

XII.  ^he  Fluxion  of  any  Power  of  afiowing 
^antity.  Lemma  premifed  in  order  to 
examine  the  method  for  finding  fucb 
Fluxion. 

XIII.  The  rule  for  the  Fluxions  of  Powers 
attained  by  unfair  reafoning, 

XIV.  The  aforefaid  re afoning  farther  unfold-^ 
ed  andjloew'd  to  be  illogical 

XV.  No  true  Conclufion  tobe  jufily  drawn  by 
dire6l  confequence  from  incon/ifient  Sup^ 
pojitiom.  The  fame  Rules  of  right  rea-^ 
fon  to  be  obfer^ved^  whether  Men  argue 

in  Symbols  or  in  Words, 

XVI.  An  Hypothefis  being  defiroyed^noconfe^ 
quence  offuch  Hypothefis  to  be  retained, 

XVII.  Hard  todifiinguifij  between  evanefcent 
Increments  and  infinitefimal  Differences, 
Fluxions  placed  in  various  Lights,  The 
great  Author^  it  feemsy  not fatisfied  with 
his  own  Notions. 

XVIII.  ^^/f- 


The  CONTENTS. 

XVIU.  ^4mt^iesinjituielyfmallfid^fiqfed  and 
rejeBed  by  Leiboitz  and  Ms  Polbwers. 
3S[o  ^antityy  according  ^o  them^  greater 
orfmaUerfar  .the  Addkim  or  Subdue^ 
tion  of  its  InfiniteJimaL 

XIX.  CmcJyfions  io  he ^Dvtd  byibe  Princi^ 
ples^and  not  Principles  by. the  Gonclu/ions. 

XX.  The  Geometrical  Analyft  confidered  as  a 
Logician'^  and  his  Di/coverieSy  mot  in 
themfehes^  iut  4is  derived  fram  fucb 
Principles  and  byfuch  Inferences. 

XXI.  A  I'angent  drmsDnto, the  Parabola  ac-^ 
cording  to  the  calculus  difFerentialis. 
"Truth Jhewn  to  be  the  refult  oferror^  and 
how, 

XXII.  3y  vlrjiut  of  a  (twofold  miftake  Ana* 
lyjls  arrive  at  Truthjxutmt  at  Science  : 
ignorant  how  they  come  at  their  own 
Concliifions, 

XXIII.  The  Conclupon  never  evident  or  accu-^ 
rate^  in  viitue  cf  ibfcure  or  inaccurate 
Premifes.  Pinite  '^antities  mi^ht  be 
rejeUed  as  well  as  Infiniiefimals. 

XXIV.  The  foregoing  DjsBrit^  farther  illu* 
ftraied.  XXV.  Sundr^f 


Tte  CONTENTS. 

jtXV.  Sundry  Obfirvathns  thereupon. 

XXVI.  Ordinate  found  fram  the  Area  by 
means  of  evanefcent  Increments. 

XXVII.  In  the  foregoing  Cafe  the  fuppofed 
evanefcent  Increment  is  realty  a  finite 
^antity,  defiroyed  by  ojj  equal  ^aniity 
mth  an  oppofite  Sign. 

XXVIII.  ^he  foregoing  Cafe  fut  generally. 
Algebraical  ExpreJ/ions  compared  with 
Geometric  at  ^anfitiiS. 

XXIX.  Correfpondent  ^antities  Algebraical 
and  Geometrical  equated.  The  Analyfis 
fhe*wed  not  to  obtain  in  Infintefnvals^  hut 

it  muji  alfo  obtain  infinite  ^antities. 

XXX.  The  getting  rid  of  ^antities  by  the 
received  Principles,  whether  of  Fluxions 
or  of  Differ ences,  neither  good  Geometry 
nor  good  Logic.  Fluxions  or  Velocities, 
i»hy  introduced, 

XXXI.  Velocities  not  to  be  abfiraEted  from 
Ttme  and  Space:  Nor  their  Proportions 
to  be  invefiigated  or  confidered  exclufively 
ofJime  and  Space. 

XXXII.  Dijicult 


The   CONTENTS. 

XXXII.  Difficult  andobfcure  Points  conjlitufe 
the  Principles  of  the  modern  Analyjis^  and 
are  the  Foundation  on  which  it  is  built. 

XXXIIL  The  rational  Faculties  whether  im^ 
proved  byfuch  objcure  Analytics. 

XXXIV.  By  what  inconceivable  Steps  finite 
Lines  are  found  proportional  to  Fluxions, 
Mathematical  Infidels  firain  at  a  Gnat 
andfwallow  a  Camel, 

XXXV.  Fluxions  or  Infinitefimalsmt  to  bea- 
voided  on  the  received  Principles.  Nice  Ab" 
firaBions  and  Geometrical  Metaphyfics.     - 

XXX VI.  Velocities  of  nafcent  or  evanefcent 
^antities^  whether  in  reality  underfiood 
andfignified  by  finite  Lines  and  Species. 

XXXVII.  Signs  or  Exponents  obvious-^  but' 
Fluxions  the mf elves  not  fi. 

XXXVIII.  Fluxions^  whether  the  Velocities 
with  which  infinitefimal  Differences  are 
generated  ? 

XXXIX.  Fluxions  of  Fluxions  or  fecond 
Fluxions^^  whether  to  be  conceived  as  Velo- 
cities of  VclocitieSy  or  rather  as  Velocities 
of  the  fecond  nafcent  Increments? 

XL,  Fluxions 


The   CO  NT  E  NTS. 

XL.  Fluxions  confidered,  fometimes  in  oni 
Senfe^  fometimes  in  another :  One  while  in 
themfehes^  another  in  their  Exponents : 
Hence  Confujion  and  Obfcurity, 

XLI.  Ifochronal  Increments^  whether  finite  or 
ndfcenty  proportional  to  their  refpeEiive 
Velocities. 

XLII.  T'ime  fuppofed  to  be  divided  into  Mo^ 
ments:  Increments  generated  in  thofe 
Moments :  And  Velocities  proportional  to 
thofe  IncrementSi 

XLIII.  Fluxions^  fecond,  thirds  fourthy  &c. 
*wh^t  they  are;  how  obtained,  and  how  re'- 
prefented.  What  Idea  of  Velocity  in  a  Mo^ 
ment  of  Time  and  Point  of  Space. 

XLIV.  Fluxions  of  all  Orders  inconceivable;^ 

XLV.  Signs  or  Exponents  confounded  with 
the  Fluxidnii 

XLVI.  Series  of  Expffjions  or  of  Notes  eafily 
contrived.  Whether  a  Series,  of  mere  Ve- 
locities, or  of  mere  nafcent  Increments^ 
cerrefponding  thereunto,  be  as  eafily  con^ 
teivtdf 

B  j^y.  Cekriliei. 


The  CONTENT! 

XL VII.  Celerities  difmijfed,  and  injiead  there* 
of  Ordinates  and  Areas  introduced,  Ana^ 
logies  and  Exprejfiom  ufeful  in  the  modern 
^adratiireSy  may  yet  be  ufelefs  for  ena- 
bling us  to  conceive  Fluxions,  No  right 
to  apply  the  Rules  without  knowledge  of 
the  Principles, 

XLVIII.  Metaphyjics  of  modern  Analyjis  mojl 
incomprehenfble. 

XLIX.  Analyjis  employ* d  about  notional  Jl:>a'* 
dowy  Entities,  Their  Logics  as  exception 
nable  as  their  Metaphyjics. 

L.  Occafion  of  this  Addrefs,  Conclujiont 
Queries. 


THE 


t  H  E 


ANALYST. 


I.  ^5SSS^^23SHOtJGli  i  ama  Stranger 
to  your  Perfon,  yet  I  am  not. 
Sir,  a  Stranger  to  the  Repu- 
tation you  have  acquired,  in 
that  branch  of  Learning  which  hath  beeli 
your  peculiar  Study ;  nor  to  the  Authority 
that  you  therefore  aflume  in  things  foreign 
to  your  Profeffion,  nor  to  the  Abufe  that 
you,  and  too  many  more  of  the  like  Cha- 
rader,  are  known  to  make  of  fuch  tindu6: 
Authority,  to  the  mifleading  of  tinwary 
Perfons  in  matters  of  the  higheft  Con- 
cernment, and  whereof  your  mathemati- 
cal Knowledge  can  by  no  means  qualify 
you  to  be  a  competent  Judge.  Equity  in- 
deed and  good  Senfe  would  incline  one  to* 
difiregar d  the  Judgment  of  Men,  in  Points* 
B  2  whielif 


Thb    Analyst; 

III.  The  Method  of  Fluxions  is  the  ge- 
neral Key,  by  help  whereof  the  modern 
Mathematicians  unlock  the  fecrets  of  Geo- 
metry, and  confequcntly  of  Nature.     And 
as  it  is  that  which  hath  enabled  them  fq 
remarkably  to  outgo  the  Ancients  in  difr 
covering  Theorems  and  folving  Problems, 
the  exercifc  and  application  thereof  is  be- 
come the  main,    if  not  fole,  employment 
of  all  thofe  who  in  this  Age  pafs  for  pro- 
found Geometers.   But  whether  this  Me- 
thod be  clear  or    obfcure,     confiftent    or 
I'epugnant,  demonftrative  or  precarious,  as 
I    {hall  inquire  with  the  utmoft    impar- 
tiality, fo  I  fubmit  my  inquiry    to    your 
own  Judgment,  and  that  of  every  candid 
Reader;   Lines  arc  fuppofed  to  be  gene- 
rated *  by  the  motion  of  Points,    Plains 
by  the  motion  of  Lines,    and  Solids    by 
the  motion  of  plains.  And  whereas  Quan- 
tities generated  in  equal  times  are  greater 
or    leffer,    according  to    the  greater     or 
leffer  Veltcity,   wherewith  they  increafe 
and   are  generated,  a  Method  hath  been 
found  to  determine  Quantities   from  the 
Velocities   of    their   generating   Motions. 

*  Introd.  ad  Quadraturam  Curvarum. 

And 


The   a  n  a  t  y  s  tJ  f, 

And  fuch  Velocities  are  called  Fluxions: 
and  the  Quantities  generated  are  called 
flowing  Quantities.  Thefe  Fluxions  are 
faid  to  be  nearly  as  the  Increments  of 
the  flowing  Quantities,  generated  in  the 
leaft  equal  Particles  of  time ;  and  to  be 
accurately  in  the  firft  Proportion  of  the 
nafcent,  or  in  the  laft  of  the  evanefcenr, 
Increments.  Sometimes,  inftead  of  Velo- 
cities, the  momentaneous  Increments  or 
Decrements  of  undetermined  flowing 
Quantities  are  confidered,  under  the  Ap* 
pellation  of  Moments. 

IV.  By  Moments  we  are  not  to  under- 
fl:and  finite  Particles.  Thefe  are  faid  not 
to  be  Moments,  but  Quantities  genera- 
ted from  Moments,  which  laft  are  only 
the  nafcent  Principles  of  finite  Quanti- 
ties. It  is  faid,  that  the  minuteft  Errors 
are  not  to  be  negled:ed  in  Mathematics : 
that  the  Fluxions  are  Celerities,  not  pro- 
portional to  the  finite  Increments  though 
ever  fo  fmall ;  but  only  to  the  Moments 
or  nafcent  Increments,  whereof  the  Pro- 
portion alone,  and  not  the  Magnitude,  is 
confidered.  And  of  the  aforefaid  Fluxions 
^  4  there 


P  T  H  E     A  N  A  L  y  S  T. 

there  be  other  Fluxions,  which  Fluxions 
pf  Fluxions  are  called  fecond  Fluxions. 
And  the  Fluxions  of  thefe  fecond  Fluxions 
are  called  third  Fluxions  :  and  foon,  fourth, 
fifth,  fixth,  &c.  ad  infinitum.  Now  as  our 
Senfe  is  ftrained  and  puzzled  with  the 
perception  of  Objedls  extremely  minute, 
even  fo  the  Imagination,  which  Faculty 
derives  from  Senfe,  is  very  much  ftrained 
^nd  puzzled  to  frame  clear  Ideas  of  the 
leaft  Particles  of  time,  or  the  leaft  Incre- 
nients  generated  therein  :  and  much  more 
fo  to  comprehend  the  Moments,  oi: 
thofe  Increments  of  the  flowing  Quanti- 
ties in  Jiatu  nafientiy  in  their  very^  firft 
origin  or  beginning  to  exift,  before  they 
become  finite  Particles.  And  it  feems  ftill 
more  difficult,  to  conceive  the  abftradled 
Velocitie?  of  fuch  nafcent  impeffed  En- 
tities. But  the  Velocities  of  the  Velocities, 
the  fecond,  third,  fourth  and  fifth  Velo- 
cities, ^c,  exceed,  if  I  miftake  not,  all 
Humane  Underftanding.  The  further  the 
Mind  analyfeth  aqd  purfueth  thefe  fugi- 
tive Ideas,  the  niore  it  is  loft  and  be- 
yv^ildered;  the  Objeds,  at  firft  fleeting  and 
piinute,  foon  vanifbing  put  of  fight.  Cer- 
tainly 


The   Analy  s  t, 

tainly  In  any  Senfe  a  fecond  or  third 
Fluxion  feems  an  obfcure  Myflery.  The 
incipient  Celerity  of  an  incipient  Celerity, 
the  nafcent  Augment  of  a  nafcent  Aug- 
ment, /.  e,  of  a  thing  which  hath  no 
Magnitude:  Take  it  in  which  light  you 
pleafe,  the  clear  Conception  of  it  will,  if 
I  miftake  not,  be  found  impofiible,  whe- 
ther it  be  fo  or  no  I  appeal  to  the  trial 
of  every  thinking  Reader.  And  if  a  fecond 
Fluxion  be  inconceivable,  what  are  we  to 
think  of  third,  fourth,  fifth  Fluxions,  and 
fo  onward  without  end  ? 

V.  The  foreign  Mathematicians  are 
fuppofed  by  fome,  even  of  our  own,  to 
proceed  in  a  manner,  lefs  accurate  per- 
haps and  geometrical,  yet  more  intelligi- 
ble. Inftead  of  flowing  Qu^antities  and 
their  Fluxions,  they  confider  the  variable 
finite  Quantities,  as  increafing  or  dimi- 
nifhing  by  the  continual  Addition  or  Sub- 
dudion  of  infinitely  fmall  Quantities.  In- 
ftead of  the  Velocities  wherewith  Incrc- 
nients  are  generated,  they  confider  the  In- 
crements or  Decrements  themfelves,  which 
;hey  call  Differences,  and  which  are  fup- 
pofed 


to  THEANALYSrr 

pofed  to  be  infinitely  fmall.  The  Diffe-* 
rence  of  a  Line  is  an  infinitely  little  Line ; 
of  a  Plain  an  infinitely  little  Plain.  They 
fuppofe  finite  Quantities  to  confift  of  Parts 
infinitely  little,  and  Curves  to  be  Poly* 
gones,  whereof  the  Sides  are  infinitely  lit- 
tle, which  by  the  Angles  they  make  one 
with  another  determine  the  Curvity  of 
the  Line.  Now  to  conceive  a  Quantity  in* 
finitely  fmall,  that  is,  infinitely  lefs  than 
any  fenfible  or  imaginable  Quantity,  or 
than  any  the  leaft  finite  Magnitude,  is,  J 
confefs,  above  my  Capacity.  But  to  con-» 
ceive  a  Part  of  fuch  infinitely  fmall  Quan- 
tity, that  fhall  be  ftill  infinitely  lefs  than 
it,  and  confequently  though  multiply*d 
infinitely  fliall  never  equal  the  ipinuteft 
finite  Quantity,  is,  I  fufpedl,  an  infinite 
Difficulty  to  any  Man  whatfoever;  and 
will  be  allowed  fuch  by  thofe  who  can- 
didly fay  what  they  think ;  provided  they 
really  think  and  refle<ft,  and  do  not  take 
things  upon  truft. 

VI.  And  yet  In  the  calculus  differentialit^ 
which  Method  ferves  to  all  the  fame  In- 
tents  and  Ends   v^ith  that    qf   Fluxions, 

our 


T  H  E    A  N  A  L  y  S  T.  II 

pur  modern  Analyfts  are  not  content   to 
confider    only   the  Differences    of   finite 
Quantities:  they  alfo  confider  the   Differ 
rences  of  thofe  Differences,  and  the  Diffe- 
rences of  the  Differences  of  the  firfl  Diffe- 
rences.    And  fo  on  ad  infinitum.     That  is, 
they  confider  Quantities  infinitely  lefs  than 
the  leafl  difccrnible  Quantity  ;  and  others 
infinitely  lefs  than  thofe  infinitely  fmall  oncsj 
and  flill  others  infinitely  lefs  than  the  prece- 
ding Infinitefimals,  and  fo  on  without  end 
pr  linaic.     Infomuch   that  we  are  to  ad- 
pit  an  infinite  fucceflion  of  Infinitefimals, 
each  infinitely    lefs    than  the    foregoing, 
$ind  infinitely  greater  than  the  following* 
As  there  are  firfl,  fecond,  third,   fourth, 
iifth,   Csfr,  Fluxions,    fo  there  are  Diffe- 
rences, firft,  fecond,  third,  fourth,  &fr.  in 
$in  infinite   ProgrefHon  towards    nothing, 
which  you  ftill  approach  and  never  arrive 
at.     And  (which  is  nKjfl  ftrange)  although 
you  (hould  take  a  Million  of  Millions  of 
thefe  Infinitefinaals,  each   whereof  is  fup- 
pofed  infinitely  greater   than   fome  other 
real  Magnitude,  and  add  them  to  the  leaft 
given  Quantity,  itfhall  be  never  the  bigger. 
For  this  is  one  gf  the  modefl  pojtulata  of 

pur 


rt  T  H  E     A  N  A  L  Y  S  T? 

our  modern  Mathematicians,  and  is  a  Cor- 
ner-ftone  or  Ground-work  of  their  Specu- 
lations. 

•  VII.  All  thefe  Points,  I  fay,  are  fup- 
pofed  and  believed  by  certain  rigorous  Ex- 
a<ftors  of  Evidence  in  Religion,  Men  who 
pretend  to  believe  no  further  than  they 
can  fee.  That  Men,  who  have  been  con- 
verfant  only  about  clear  Points,  fhould 
with  difficulty  admit  obfcure  ones  might 
not  feem  altogether  unaccountable.  But 
he  who  can  digeft  a  fecond  or  third  Fluxi- 
on, a  fecond  or  third  Difference,  need  not, 
methinks,  be  fqueamifli  about  any  Point 
in  Divinity.  There  is  a  natural  Prefump- 
lion  that  Mens  Faculties  are  made  alike. 
It  is  on  this  Suppofition  that  they  attempt 
to  argue  and  convince  one  another.  What, 
therefore,  Ihall  appear  evidently  impoffi- 
ble  and  repugnant  to  one,  may  be  pre- 
fumed  the  fame  to  another.  But  with 
what  appearance  of  Reafon  {hall  any  Man 
prefume  to  fay,  that  Myfteries  may  not 
be  Objedts  of  Faith,  at  the  fame  time  that 
he  himfelf  admits  fuch  obfcure  Myfteries 
to  be  the  Obje(^  of  Science  ? 

VIII.  It 


Irviii 


The   a  k  a  l  V  s  t.  "i'f 

VIIL  It  mu ft  indeed  be  acknowledged, 
the  modern  Mathematicians  do  not  confi- 
der  thefe  Points  as  Myfteries,  but  as  clear- 
ly conceived  and  maftered  by  their  com- 
prehenfive  Minds.  They  fcruple  not  to 
fay^  that  by  the  help  of  thefe  new  Analy-^ 
tics  they  can  penetrate  into  Infinity  it  felf  i 
That  they  can  even  extend  their  Views  be- 
yond Infinity  :  that  their  Art  comprehends 
not  only  Infinite,  but  Infinite  of  Infinite  (as 
they  exprefs  it)  or  an  Infinity  of  Infinites^ 
But,  notwithftanding  all  thefe  Aflfertions 
and  Pretenfions,  it  may  be  juftly  queftibn- 
ed  whether,  as  other  Men  in  other  Inqui>- 
ries  are  often  deceived  by  Words  or  Terms-, 
fo  they  like  wife  are  not  wonderfully  de- 
ceived and  deluded  by  their  own  peculiar 
Signs,  Symbols,  or  Species.  Nothing  iseafier 
than  to  devife  Expreflions  or  Notations  for 
Fluxions  and  Infinitefimals  of  the  firft,  fc-^ 
cond,  third,  fourth  and  fubfequent  Orders^ 
proceeding  in  the  fame  regular  form  with-* 
out  end  or  limit  x\  ^^  ^'  ^;,  Gfc.  or  dx,  ddx, 
dddx,  ddddx  &c,  Thefe  Expreflions  in- 
deed arc  clear  and  diftindl,  and  the  Mind 
finds  no  difficulty  in  conceiving  them  to 
be  continued  beyond  any  aflignable  Bounds; 

But 


14  The    ANALVst. 

fiiit  if  we  remove  the  Veil  and  look  uric(ef-. 
neath,  if  laying  afide  the  Expreflions  wc 
fct  our  felves  attentively  to  confider  the 
things  themfelves,  which  are  fuppofed  to 
be  expreffed  or  marked  thereby,  we  fhall 
difcover  much  Emptinefs,  Darknefs,  and 
Confufion  j  nay^  if  I  miftake  not>  direft 
Impoffibilities  and  Contradictions.  Whe- 
ther this  be  the  cafe  or  no,  every  think- 
ing Reader  is  intreated  to  examine  and 
judge  for  himfelfi 

iX.  Having  cotifidered  the  ObjcdV,  I 
proceed  to  confider  the  Principles  of  this 
pew  Analyfis  by  Momentums,  Fluxions^  or 
Infinitefimals ;  wherein  if  it  (hall  appear 
that  your  capital  Points,  upon  which  the 
reft  are  fuppofed  to  depend,  include  Er- 
ror and  falfe  Rcafoning  j  it  will  then  fol- 
low that  you,  who  are  at  a  lofs  to  eon- 
dud  your  felves,  cannot  with  any  decen- 
cy fet  up  for  guides  toother  Mcri.  The 
main  Point  in  the  method  of  Fluxions  is 
to  obtain  the  Fluxion  or  Momentum  of 
the  Redtangle  or  Produdt  of  two  indetef- 
fninate  Quantities.  Inafmuch  as  from 
thence  arc  derived  Rules  for  obtaining  thd 

Fluxiofitr 


The    ANALYst.  ij^ 

Fluxions  of  all  other  ProduiSts  and  Pow- 
ers; be  the  Coefficients  or  the  Indexes  what 
they  will,  integers  or  fradtions,  rational 
or  furd.  Now  this  fundamental  Point 
one  would  think  fhould  be  very  clearly 
made  out,  confidering  how  much  is  built 
upon  it,  and  that  its  Influence  extends 
throughout  the  whole  Analyfis.  But  let 
the  Reader  judge.  This  is  given  for  De- 
monftration.  *  Suppofe  the  Produd:  or 
Redangle  AB  increafed  by  continual  Mo- 
tion: and  that  the  momentaneous  Incre- 
ments of  the  Sides  A  and  B  are  a  and  i^ 
When  the  Sides  A  and  B  were  deficient,  or 
lelTer  by  one  half  of  their  Moments,  the  Rect- 
angle was  ji^—^a  xi^. — i^  i.e.  AB—^^aB 
^^ibji-^-iab.  And  as  foon  as  the  Sides 
A  and  B  are  increafed  by  the  other  twa 
halves  of  their  Moments,  the  Rectangle 
becomes  ^TT^  ^  FTT^or  AB-^iaB^ 
ibA-^r-ab,  From  the  latter  Redangle 
fubdudl  the  former,  and  the  remaining  difFc* 
fence  will  be  aB-^bA.  Therefore  the 
Increment  of  the  Redangle  generated  by 
the  intire  Increments  a  and  b\s  aB'\-bA, 

r 
*  Naturalis   Philofophix    principia   mathematica,    I.  z. 
km.  2. 


1  tf  T  H  E     A  N  A  L  Y  S  t. 

^jE.  jD.  But  it  is  plain  that  the  direct: 
and  true  Method  to  obtain  the  Moment  or 
Increment  of  the  Rectangle  jiB^  is  to  take 
the  Sides  as  increafed  by  their  whole  In- 
crements, and  (o  multiply  them  together*, 
A-^-a  by  5  +  ^,  the  Produdt  whereof 
jiB  +  aB  +  6A'\'ab  is  the  augmented 
Redlangle-  whence  if  we  fubdudl  AB^  tht 
Rerriainder  aB  +  iA  +  aif  will  be  the  trub 
Increment  of  the  Reftangle,  exceeding 
that  which  was  obtained  by  the  former 
illegitimate  and  indiredl  Method  by  the 
Quantity  ab.  And  thfS  holds  univerfally 
be  the  Quantities  a  and  i  what  they  will, 
big  or  little,  Finite  or  Infinitefimal,  Incre- 
ments, Moments,  or  Velocities.  Nor  will 
it  avail  to  fay  that  a^  is  a  Quantity  ex- 
ceeding fmall  t  Sihct  we  are  told  that  in  re-^ 
bus  mathematicis  errores  quam  minimi  nOn 
funt  contemnendi,  *  Such  reafoning  as  this,, 
for  Demonftration,  nothing  but  the  obfcurity 
of  the  Subject  could  have  encouraged  or  indu- 
ced the  great  Author  of  the  Fluxionary  Me- 
thod to  put  upon  his  Followers,  and  nothing 
but  an  implicit  deference  to  Authority  couH 
move  them  to  admit.     The  Cafe  indeed  is 

*  Imrod.  ad  Quadraturam  Curvarum. 

difBcufc 


T  H   E     A  N  A  L  V  S  t.  17. 

difficult.  There  can  be  nothing  done  till 
you  have  got  rid  of  the  Quantity  a  b.  In 
order  to  this  the  Notion  of  Fluxions  is 
fhifted:  It  is  placed  in  various  Lights: 
Points  which  fhould  be  clear  as  firft  Prin-^ 
ciples  are  puzzled  3  and  Terms  which 
fhould  be  fteadily  ufed  are  ambiguous. 
But  notwithftanding  all  this  addrefs  and 
skill  the  point  of  getting  rid  oi  ab  can- 
not be  obtained  by  legitimate  reafoning.  ^ 
If  a  Man  by  Methods,  not  geometrical  or 
demonftrative,  (hall  have  fatisfied  himfelf 
of  the  ufefulnefs  of  certain  Rules;  which 
he  afterwards  (hall  propofe  to  his  Difciples 
for  undoubted  Truths;  which  he  under- 
takes to  demonftrate  in  a  fubtile  man- 
ner, and  by  the  help  of  nice  and  in- 
tricate Notions  5  it  is  not  hard  to  conceive 
that  fuch  his  Difciples  may,  to  fave  them- 
felves  the  trouble  of  thinking,  be  inclined 
to  confound  the  ufefulnefs  of  a  Rule  with 
the  certainty  of  a  Truth,  and  accept  the 
one  for  the  other;  efpecially  if  they  are 
Men  accuftomed  rather  to  compute  than  to 
think;  earneft  rather  to  go  on  faft  and  far, 
than  folicitous  to   fee  out  warily  and  fee 

their  way  diftindtly. 

C  XI.  The 


I  8  T  H  E    A  N  A  t  r  S  T. 

XL  The  Points  or  meer  Limits  of  nal- 
cent  Lines  are  undoubtedly  equals  as  hav- 
ing no  more  magnitude  one  than  ano- 
ther, a  Limit  as  fuch  being  no  Quantity. 
If  by  a  Momentum  you  mean  more  than 
the  very  initial  Limit,  it  muft  be  either  a 
finite  Quantity  or  an  Infinitefimal.  But 
all  finite  Quantities  are  exprefly  excluded 
from  the  Notion  of  a  Momentum.  There* 
^  fore  the  Momentum  muft  be  an  Infini- 
tefimal. And  indeed,  though  much  Ar- 
tifice hath  been  employed  to  efcape  or  a- 
void  the  admiffion  of  Quantities  infinitely 
fmall,  yet  it  feems  ineifedtual.  For  ought 
I  fee,  you  can  admit  no  Quantity  as  a 
Medium  between  a  finite  Quantity  and 
nothing,  without  admitting  Infinitefimals. 
An  Increment  generated  in  a  finite  Parti- 
cle of  Time,  is  it  felf  a  finite  Particle ; 
and  cannot  therefore  be  a  Momentum^ 
You  muft  therefore  take  an  Infinitefimal 
Part  of  Time  wherein  to  generate  your 
Momentum.  It  is  faid,  the  Magnitude  of 
Moments  is  not  confidered :  And  yet  thefe- 
fame  Moments  are  fuppofed  to  be  divided 
into  Parts.  This  is  not  eafy  to  conceive,, 
no  more  than  it  is  why  we  fhould  take 

Quantities' 


T  H  E    A  N  A  L  Y  S  ir;  ffll 

Qoantities  lefs  than  A  and  5  in  order  to 
obtain  the  Increment  of  A  By  of  which 
proceeding  it  muft  be  owned  the  final 
Caufe  or  Motive  is  very  obvious;  but  it 
is  not  fo  obvious  or  eafy  to  explain  a  juft 
and  legitimate  Reafon  for  it,  or  (hew  it 
to  be  Geometrical. 

XII.  From  the  foregoing  Principle  fo 
demonftrated,  the   general  Rule  for  find- 
ing the  Fluxion  of  any  Power  of  a  flow- 
ing Qujantity  is  derived  *.     But,  as  there 
feems  to  have  been  fome  inward  Scruple 
or  Confcioufnefs  of  defed:  in  the  forego- 
ing Deraonftration,  and  as  this  finding  the 
Fluxion  of  a  given  Power  is  a  Point  of 
primary  Importance,     it    hath    therefore 
been  judged    proper    to    demonftrate    the 
fame  in  a  different  manner  independent  of 
the  foregoing  Demonftration.     But  whe- 
ther this  other  Method  be  more  legitimate 
and  conclufive  than    the  former,    I  pro- 
ceed now  to  examine  j  and  in  order  there- 
to (hall   premife  the    following  Lemma. 
"  If  with   a   V^iew   to   demonftrate    any 

*  Philofophije   naturalis   principia  Mathematica,  lib.  2. 
lem.  2. 

B  2  ^  Propo- 


;3L0  T  HE     A  N  A  L  Y  S  f, 

*^  Propofition,  a  certain  Point  is  fuppofcd, 
"  by  virtue  of  which  certain  other  Points 
*^  ^re  attained;  and  fuch  fuppofed  Point 
"  be  it  feif  afterwards  dcftroyed  or  rejec- 
"  ted  by  a  contrary  Suppofition ;  in  that 
"  cafe,  all  the  other  Points,  attained  thereby 
"  and  confequent  thereupon,  muft  alfo 
"  be  deftroyed  and  rejeded,  fo  as  from 
"  thence  forward  to  be  no  more  fuppo- 
"  fed  or  applied  in  the  Dcmonftration." 
This  is  fo  plain  as  to  need  no  Proot 

XIII.  Now  the  other  Method  of  ob- 
taining a  Rule  to  find  the  Fluxion  of  any 
Power  is  as  follows.  Let  the  Quantity  x 
flow  uniformly,  and  be  it  propofed  to  find 
the  Fluxion  of  x"»  In  the  fame  time 
that  X  by  flowing  becomes  x  +  o^y  the 
Power  a:»  becomes  x-\-o\ »  ,  i.  e.  by  the 
Method   of  infinite  Series  x^  +  nox^  —  ^ 


+  '^''^  -oox"  ^  +  £f^.  and  the  Incre- 
ments 0  and    nox^  —  ^  -f  lUZf  ^o^v^—z 

2 

4-  &c,  are  one  to  another  as  i  to  «;c»~i 
^  IJLlLJLoxn—^  +  0*c.  Let  now  the  In- 
crements vanifli,  and  their  laft  Proportion 
will  be  I  to  «x»  —  ^     Butitfliould  feem 

that 


I 


T  H  E     A  N  A  L  Y  S  T-  11 

that  this  reafoning  is  not  fair  or  conclufive. 
For  when  it  is  faid,  let  the  Increments 
vanifh,  /.  e,  let  the  Increments  be  nothing, 
or  let  there  be  no  Increments,  the  former 
Suppofition  that  the  Increments  were 
fomething,  or  that  there  were  Increments,  is 
deftroyed,  and  yet  a  Confequence  of  that 
Suppofition,  i,  e,  an  Expreflion  got  by 
virtue  thereof,  is  retained.  Which,  by 
the  foregoing  Lemma,  is  a  falfe  way  of 
reafoning.  Certainly  when  we  fuppofe 
the  Increments  to  vanifh,  we  muft  fup- 
pofe their  Proportions,  their  Expreflions, 
and  every  thing  elfe  derived  from  the  Sup- 
pofition of  their  Exiftcnce  to  vanifh  wittt 
theoi. 


XIV.  To  make  this  Point  plainer,- -J 
lift  fliall  unfold  the  reafoning,  and  propofe  Jt 
in  a  fuller  light  to  your  View.  It  amounts 
therefore  to  this,  or  may  in  other  Words 
be  thus  expreflfed.  .  I  fuppofe  that  the 
Quantity  x  flows,  and  by  flowing  is  in- 
creafed,  and  its  Increment  I  call  o,  fo 
that  by  flowing  it  becomes  x-^-o.  And 
as  X  increafcth,  it  follows  that  every  Power 
of  X  is  likewife  increafed  in  a  due  Pro- 
C  3  portion. 


tjf,  The    AaN^^lyst* 

portion.  Therefore  as  x  becomes  x-irJ?, 
A?«  will  become  x  -^  o\":  that  is,  .accord- 
ing to  the  Method  of  infinite   Series,  ^« 

+  nox""—^  -V^-^^-^oox^—^  +  &c.     And 

2 

if  from  the  two  augmented  Quantities  we 
fubdud  the  Root  and  the  Power  refpec^ 
lively,  we  fhall  have  remaining  the  two 
Increments,  to  wit,  o  and  nox^—'^  + 
^'—-^oox^  —  '^  4-  G'r.  which  Increments, 
being  both  divided  by  the  common  Divi- 
for  Oy  yield  the  Quotients  i  and  nx^  —  ^ 

■4-  l^'^^ox^  —  ^  4-  &c.  which  are  there- 
fore Exponents  of  the  Ratio  of  the  Incre- 
ments. Hitherto  I  have  fuppofed  that  x 
flows,  that  X  hath  a  real  Increment,  that 

0  is  fomething.     And  I  have  proceeded  all 
1       along  on  that  Suppofition,  without  which 

1  fhould  not  have  been  able  to  have  made 
fo  much  as  one  fingle  Step.  From  that 
Suppofition  it  is  that  I  get  at  the  Incre- 
ment of  a:»,  that  I  am  able  to  compare 
it  with  the  Increment  of  Xy  and  that  I 
find  the  Proportion  between  the  two  In- 
crements. I  now  beg  leave  to  make  a 
new  Suppofition  contrary  to  the  firft,  /.  e, 
I  will  fuppofc  that  there  i?  no  Increment 

of 


T  H  E     A  N  A  L  Y  S  T.  I5 

of  AT,  or  that  0  IS  nothing  ;  which  fecond 
Suppofition  deftroys  my  firft,  and  is  in- 
confiftent  with  it,  and  therefore  with  eve- 
ry thing  that  fuppofeth  it.  I  do  never- 
thelefs  beg  leave  to  retain  ^a:»  — »,  which 
is  an  Expreffion  obtained  in  virtue  of  my 
firft  Suppofition,  which  neceffarily  pre- 
fuppofeth  fuch  Suppofition,  and  which 
could  not  be  obtained  without  it :  All 
which  feems  a  moft  inconfifl:ent  way  of 
arguing,  and  fuch  as  would  not  be  allow- 
ed of  in  Divinity. 

XV.  Nothing  is  plainer  than  that  ih 
jufl:  Conclufion  can  be  diredly  drawn  from 
two  inconfiftent  Suppofitions.  You  may 
indeed  fuppofe  any  thing  poflible  :  But  af- 
terwards you  may  not  fuppofe  any  thing 
^^that  deftroys  what  you  firft  fuppofed.  Or 
'  if  you  do,  you  muft  begin  de  novo.  If 
therefore  you  fuppofe  that  the  Augments 
vanifli,  i,e,  that  there  arc  no  Augments, 
you  are  to  begin  again,  and  fee  what  fol- 
lows from  fuch  Suppofition.  But  nothing 
will  follow  to  your  purpofe.  You  cannot 
by  that  means  ever  arrive  at  your  Con- 
clufion,  or  fugceed  In,  what  is  called  by 

B  4  the 


5t4  .The   Anal  y  s^t. 

the  celebrated  Author,    the  Inveftigation 
of  the  firft  or  laft  Proportions  of  nafcent 
and  evanefcent  Quantities,    by  inftituting 
the  Analyfis   in  finite  ones.     I  repeat  it 
again:  You  are  at    hberty  to  make  any 
poflible  Suppofition:    And  you   may  de- 
ftroy  one    Suppofition  by    another:    But 
then  you  may  not  retain  the  Confequences, 
or  any  part   of  the  Confequences  of  your 
firft    Suppofition   fo    deftroyed.     I  admit 
that  Signs  may  be  made  to  denote  either 
any  thing  or  nothing :  And  confequently 
that  in  the  original  Notation  x-\-  Oy  o  might 
have  fignified  either  an  Increment  or  no- 
thing.    But   then  which  of  thefe  foever 
you  make  it  fignify,  you  muft  argue  con- 
fiftently  with   fuch  its   Signification,   and 
not    proceed    upon   a  double    Meaning : 
Which  to  do  were   a  manifeft  Sophifm* 
Whether   you    argue    in    Symbols    or   in 
Words,  the  Rules  of  right  Reafon  are  ftill 
the  fame.     Nor  can  it  be  fuppofed,  you 
will  plead  a  Privilege  in  Mathematics  to 
be  exempt  from  them. 

XVI.  If  you  affume  at  firft  a  Quantity 
increaf^c}  by  nothing,  and  in  the  Expref- 

fion 


The  Analyst.  15 

lion  x  +  0,  0  ftands  for  nothing,  upon  this 
Suppofition  as  there  is  no  Increment  of 
the  Root,  fo  there  will  be  no  Increment  of 
the  Power;  and  confequently  there  will 
be  none  except  the  firft,  of  all  thofe  Mem- 
bers of  the  Series  conftituting  the  Power 
of  the  Binomial ;  you  will  therefore  never 
come  at  your  Expreflion  of  a  Fluxion  le- 
gitimately by  fuch  Method.  Hence  you 
are  driven  into  the  fallacious  way  of  pro- 
ceeding to  a  certain  Point  on  the  Suppo- 
fition of  an  Increment,  and  then  at  once 
{hifcing  your  Suppofition  to  that  of  no 
Increment.  There  may  feem  great  Skill 
in  doing  this  at  a  certain  Point  or  Period. 
Since  if  this  fecond  Suppofition  had  been 
made  before  the  common  Divifion  by  c?, 
all  had  vanifhed  at  once,  and  you  muft 
have  got  nothing  by  your  Suppofition. 
Whereas  by  this  Artifice  of  firft  dividing, 
and  then  changing  your  Suppofition,  you 
retain  i  znd  nx^—K  Bli€,  notvvithftand- 
ing  all  this  addrefs  to  cover  ir,  the  fal- 
lacy is  ftill  the  fame.  For  whether  it  be 
done  fooner  or  later,  when  once  the  fe- 
cond Suppofition  or  Aflumption  is  made, 
in  the  fame  inftant  the  former  Affumpti- 

on 


^4  The   Analy^Y. 

Oft  and  all  that  you  got  by  it  is  deftroyed, 
and  goes  out  together.  And  this  is  univer- 
ifally  true,  be  the  Subjedt  what  it  will, 
throughout  all  the  Branches  of  humane 
Knowledge  ;  in  any  other  of  which,  I 
believe.  Men  would  hardly  admit  fuch  k 
reafoning  as  this,  which  in  Mathematics  is 
accepted  for  Demonftration. 

XVII.  It  may  not  be  amifs  to  obferve, 
■that  the  Method  for  finding  the  Fluxion 
of  a  Rectangle  of  two  flowing  Quantities, 
as  it  is  fet  forth  in  the  Treatife  of  Qua- 
dratures, differs  from  the  abovementioned 
taken  from  the  fecond  Book  of  the  Prin- 
ciples, and  is  in  effedl  the  fame  with  that 
ufed  in  the  calculus  different  talis  *.     For 
the  fuppofing  a  Quantity  infinitely  dimi- 
niflied  and  therefore  rejed:ing  it,  is  in  ef- 
fed:    the  rejed:ing  an  Infinitefimal;    and 
indeed  it  requires  a  marvellous  fharpnefs 
of  Difcernment,  to  be  able  to  diftinguifh 
between  evanefcent  Increments  and  infinir 
tefimal  Differences.     It   may  perhaps  be 
faid  that  the  Quantity  being  infinitely  di- 
minished   becomes  nothing,    and   fo  no- 
thing is    rejedled.     But  according  to  the 

*  Analyfe  des  infiniment  petits,  part.  i.  prop.  2. 

received 


ff        The   a  k  a  l  y  s  t.  17 

received  Principles  it  is  evident,  that  no 
Geometrical  Quantity,  can  by  any  divifion 
or  fubdivifion  whatfoever  be  exhaufted,  or 
reduced  to  nothing.  Confidering  the  var%» 
ous  Arts  and  Devices  ufed  by  the  great 
Author  of  the  Fluxionary  Method:  in 
how  many  Lights  he  placeth  his  Fluxions : 
and  in  v^hat  different  ways  he  attempts  to 
demonftrate  the  fame  Point :  one  would  be 
inclined  to  think,  he  was  himfclf  fufpici- 
Gus  of  the  juftnefs  of  his  own  demonftra- 
tions  5  and  that  he  was  not  enough  pleafed 
with  any  one  notion  fteadily  to  adhere  to 
it.  Thus  much  at  leafl:  is  plain,  that  he 
owned  himfelf  fatisfied  concerning  certain 
Points,  which  neverthelcfs  he  coqld  not 
undertake  to  demonftrate  to  others  *.  Whe- 
ther this  fatisfaftion  arofe  from  tentative 
Methods  or  Inductions  ;  which  have 
often  been  admitted  by  Mathematicians, 
(for  inftance  by  Dr.  fFallis  in  his  A- 
rithmetic  of  Infinites)  is  what  I  fliall  not 
pretend  to  determine.  But,  whatever  the 
Cafe  might  have  been  with  rcfped:  to  the 
Author,  it  appears  that  his  Followers 
{i^ve  {hewn  themfeives  more  eager  in  ap- 

*  See  Letter  to  Collins,  Nov.  8,  1676. 

plying 


The    Analyst.^ 

plying  his  Method,  than  accurate  in  exa- 
mining his  Principles. 

♦  XVIII.  It  is  curious  to  obferve,  what 
fubtilty  and  skill  this  great  Genius  em- 
ploys to  ftruggle  with  an  infuperable  Dif- 
ficulty; and  through  what  Labyrinths 
he  endeavours  to  efcape  the  Dodrine  of 
Infiniteiimals  ;  which  as  it  intrudes  up- 
on him  whether  he  will  or  no,  fo  it  is 
admitted  and  embraced  by  others  without 
the  leaft  repugnance.  Leibnitz  and  his 
Followers  in  their  calculus  differentialis 
making  no  manner  of  fcruple,  firft  to  fup- 
pofe,  and  fecondly  to  reje(5l  Quantities 
infinitely  fmall:  with  what  clearnefs  in 
the  Apprehenfion  and  juftnefs  in  the 
reafoning,  any  thinking  Man,  who  is  not 
prejudiced  in  favour  of  thofe  things,  may 
eafily  difcern.  The  Notion  or  Idea  of  an 
infinitefimal  Quantity,  as  it  is  an  Objedl 
fimply  apprehended  by  the  Mind,  hath 
been  already  confidered  *.  I  fhall  now 
only  obferve  as  to  the  method  of  getting 
rid  of  fuch  Quantities,  that  it  is  done 
without    the     leaft    Ceremony.     As     in 

*  Se^.  5  and  6. 

Fluxions 


The    a  n  a  l  y  s  Tr  a.> 

Fluxions  the  Point  of  firft  importance, 
and  which  paves  the  way  to  the  reft,  is  to 
find  the  Fluxion  of  a  Product  of  two  in- 
determinate Quantities,  fo  in  the  calculus 
differentialis  (which  Method  is  fuppofed  to 
have  been  borrowed  from  the  former  with 
fome  fmall  Alterations)  the  main  Point  is 
to  obtain  the  difference  of  fuch  Produdl. 
Now  the  Rule  for  this  is  got  by  rejecting 
the  Produdl  or  Redlangle  of  the  Differen- 
ces. And  in  general  it  is  fuppofed,  that  no 
Quantity  is  bigger  or  leffer  for  the  Addi-« 
tion  or  Subdudlion  of  its  Infinitefimal  : 
and  that  confequently  no  error  can  arife 
from  fuch  rejection  of  Infinitefimals. 

XIX.  And  yet  it  fliould  feem  that, 
whatever  errors  are  admitted  in  the  Pre- 
mifes,  proportional  errors  ought  to  be  ap- 
prehended in  the  Conclufion,  be  they  finite 
or  infinitefimal:  and  that  therefore  the 
a'jc^/jSgia  of  Geometry  requires  nothing 
fliould  be  negledted  or  rejected.  In  anfwer 
to  this  you  will  perhaps  fay,  that  the 
Conclufions  are  accurately  true,  and  that 
therefore  the  Principles  and  Methods  from 
whence   they  are  derived  muft  be  fo  too. 

But 


50  The    An  a:  l  y*  s  t. 

But   this  inverted  way  of  demonftrating^ 
your  Principles  by  your  Concluiions,  as  it 
would  be  peculiar  to  you  Gentlemen,  fo 
it  is  contrary  to  the  Rules  of  Logic.  The 
truth  of  the   Conclufion  will  not  prove 
either  the  Form  or  the  Matter  of  a  Syl- 
logifm  to  be  true :  inafmuch  as  the  Illation 
might  have  been  wrong  or  the  Premifcs 
falfe,  and  the  Conclufion  neverthelcfs  true, 
though  not  in  virtue   of  fuch  Illation  or 
of  fuch  Premifes.  I  fay  that  in  every  other 
Science  Men   prove  their  Conclufions  by 
their  Principles,and  not  their  Principles  by 
the  Conclufions.  But  if  in  yours  you  fhould 
allow  your   felves  this  unnatural  way  of 
proceeding,     the   Confequence    would  be 
that  you  muft  take  up  with  the  Inducftion, 
and  bid  adieu  to  Demonftration.    And  if 
you  fubmit  to  this,  your  Authority  will  no 
longer  lead  the  way  in  Points  of  Reafon 
and  Science. 

XX.  I  have  no  Controverfy  about  your 
Conclufions,  but  only  about  your  Logic 
and  Method.  .  How  you  demonftrate  ? 
What  Objeds  you  are  converfant  with, 
and  whether  you  conceive  them  clearly? 

What 


The    Analyst. 

What  Principles  you  proceed  upon;  how 
fpqnd  they  may  be ;  and  how  you  apply 
them?  It  muft  be  remembred  that  I  am 
not  concerned  about  the  truth  of  your 
Theorems,  but  only  about  the  way  of 
conling  at  them  ;  whether  it  be  legitimate 
or  illegitimate,  clear  or  obfcure,fcientificor 
tentative.  To  prevent  all  poflibility  of  your 
miftaking  me,  I  beg  leave  to  repeat  and 
infift,  that  I  confider  the  Geometrical  A- 
nalyft  as  a  Logician,  /.  e.  fo  far  forth  as  he 
reafons  and  argues  ;  and  his  Mathematical 
Conclufions,  not  in  themfelves,  but  in 
their  Premifes  ;  not  as  true  or  falfe,  ufe- 
ful  or  infignificant,  but  as  derived  from 
fuch  Principles,  and  by  fuch  Inferences. 
And  forafmuch  as  it  may  perhaps  fcera 
an  unaccountable  Paradox,  that  Mathe- 
maticians fliould  deduce  true  Propofitions 
from  falfe  Principles,  be  right  in  the  Con- 
clufion,  and  yet  err  in  the  Premifes ;  I  ihall 
endeavour  particularly  to  explain  why 
.  this  may  come  to  pafs,  and  fliew  how  Er- 
ror may  bring  forth  Trutb>  though  it 
cannot  bring  forth  Science. 

XXI.  la 


V 


i^ 


The   Analyst; 

XXI.  In  order  therefore  to  clear  up  this 
Point,  we  will  fuppofe  for  inftance  that  a 
Tangent  is  to  be  drawn  to  a  Parabola,  and 
examine  the  progrefs  of  this  Affair,  as  it 
is  performed  by    infinitcfimal  Differences, 


Let  AB  be  a  Curve,  the  Abfciffe  AP  —  Xi 
the  ordinate  PB==y,  the  Difference  of 
the  Abfciffe  PM=dxy  the  Difference  of 
the  Ordinate  RN=Jy,  Now  by  fuppofing 
the  Curve  to  be  a  Polygon,  and  confequenc- 
ly  BNy  the  Increment  or  Difference  of 
the  Curve,  to  be  a  ftraight  Line  coincident 

with 


T  H  E     A  N  A  L  Y  S  T-  3  5 

With  the  Tangent,  and  the  differential 
Triangle  B RN  lo  be  fimiliar  to  the  tri- 
angle TP-B  the  Subtangent  PT  is  found 
a  fourth  Proportional  to  RN:  RB:PBi 
that  is  to  Jy :  dx:  y.  Hence  the  Subtangent 

will  be  ^~,  But  herein  there  is  an  error 

arifing  from  the  forementioned  falfe  fup- 
pofition,  whence,  the  value  of  PT  comes 
out  greater  than  the  Truth  :  for  in  reality 
it  is  not  the  Triangle  RNB  but  RLB, 
which  isfimilar  to  P  B  T",  and  therefore  (in- 
ftead  o£RN)RL  fhould  have  been  the  firft 
term  of  the  Proportion,  /.  e.  RN  -{-  NL, 
i,  e.  dy  -Vzi  whence  the   true  expreflion 

for  the  Subtangent  fhould  have  been  ^^^« 

There  was  therefore  an  error  of  defedt  in 
making  dy  the  divifor  :  which  error  was 
equal  to  z,  / .  e.  NL  the  Line  comprehend* 
ed  between  the  Curve  and  the  Tangent. 
Now  by  the  nature  of  the  Cnrwc  yy=px, 
fuppofing  p  to  be  the  Parameter,  whence 
by  the  rule  of  Differences  2ydy^^pdx 
and  dy^==^^—^.  But  if  you  multiply^  -V  dy 

by   it  felf,    and  retain  the  whole  Produdt 

without  rejedling  the  Square  of  the  Diffe- 

D  rence, 


34  The    Analyst. 

rence,  it  will  then  come  out,  by  fubftitu- 
ting  the  augmented  Quantities  in  the  E- 

quation  of  the  Curve,  that  dy=-^-^^^^ 

truly.    There  was  therefore   an  error  of 

excefs  in  making  ^;'  =  ^-~,  which  followed 

from  the  erroneous  Rule  of  Differences.  And 

the  meafure  of  this  fecond  error  is  -^^  =  z. 

Therefore  the  two  errors  being  equal  and 
contrary  deftroy  each  other  ;  the  firft  er- 
ror of  defe(5l  being  corrected  by  a  fecond 
error  of  excefs. 

XXlI.  If  you  had  committed  only  one 
error,  you  would  not  have  come  at  a  true 
Solution  of  the  Problem.  But  by  virtue 
of  a  twofold  miftake  you  arrive,  though 
not  at  Science,  yet  at  Truth.  For  Science 
It  cannot  be  called,  when  you  proceed 
blindfold,  and  arrive  at  the  Truth  not 
knowing  how  or  by  what  means.    To  de- 

monftrate  that  z  is  equal  to  -^^,    let  BR 

or  dx  be  m  and  RN  or  Jy  be  n.  By  the 
thirty  third  Propofition  of  the  firft  Book  of 
the  Conies  oi  jlpolloniuSy^  and  from  fimilar 

Triangles, 


T  H  E     A  N  A  L  Y  S  t.  5  5 

Triangles,  as  2^  to;r  fo   is  m  to  «+  ^ 
=—  .    Likewife  from  the  Nature  of  tHp 

2X 

Parabola  7  ;'  +  2  yn+nn=  xp^r  mp,  and 
2yn-\-nn=^mp\  wherefore  ^-^^ ^'^ '^  =  /;7 : 

and  becaufe;'j=/>^,  y  will  be  equil 
to  X,  Therefore  fubfiitutirig  thefe  values 
inftead    of     m    and    x    we    ftiall    have 

^yUAH:    which      being      reduced      gives 

2y  zy     ^^ 

'  XXIII.  Now  I  obfervc  In  the  firft  place, 
that  the  Conclufion  comes  out  right,  not 
becaufe  the  rejefted  Square  of  dy  was  in- 
finitely fmall ;  but  becaufe  this  error  was 
compenfated  by  another  contrary  and  e^ 
qual  error.  I  obferve  in  the  fecond  places 
that  whatever  is  rejedled,  be  it  ever  {o 
fmall,  if  it  be  real  and  confequently  makes 
a  real  error  in  the  Premifes,  it  will  pro- 
duce a  proportional  real  error  in  the  Con- 
clufioni  Your  Theorems  therefore  cannot 
be  accurately  true,  nor  your  Problems 
accurately  folved,  in  virtue  of  Premifesi 
D  2  trhieh 


3,^  Th  E    A  N  A  L  Y  S  T. 

which  thcmfelves  are  not  accurate,  it  be- 
ing a  rule  in  Logic  that  Conclufio  fequitur 
partem  debiliorem.  Therefore  I  obferve  in 
the  third  place,  that  when  the  Conclufion 
is  evident  and  the  Premifes  obfcure,  or  the 
Conclufion  accurate  and  the  Premifes  in- 
accurate, we  may  fafely  pronounce  that  fuch 
Conclufion  is  neither  evident  nor  accurate, 
in  virtue  of  thofe  obfcure  inaccurate  Pre- 
mifes or  Principles;  but  in  virtue  of  fome 
other  Principles  which  perhaps  the  De- 
monftrator'  himfelf  never  knew  or  thought 
of  I  obferve  in  the  laft  place,  that  in 
cafe  the  Differences  arc  fuppofed  finite 
Quantities  ever  fo  great,  the  Conclufion 
will  neverthelefs  come  out  the  fame :  in- 
afmuch  as  the  rejed:ed  Quantities  are  le- 
gitimately thrown  out,  not  for  their 
fmallnefs,  but  for  another  reafon,  to  wir, 
becaufe  of  contrary  errors,  which  deftroy- 
ing  each  other  do  upon  the  whole  caufe 
that  nothing  is  really,  though  fomething 
is  apparently  thrown  out.  And  this  Rea- 
fon holds  equally,  with  refpedt  to  Quan- 
tities finite  as  well  as  infinitefimal,  great 
as  well  as  fmall,  a  Foot  or  a  Yard  long  as 
well  as  the  minutefl:  Increment. 

XXIV.  For 


Ipxxr 


Tbte   Analyst. 

XXIV.  For  the  fuller  illuftration  of  thisf 
Point,  I  (hall  confider  it  in  another  lighr,> 
amd  proceeding  in  finite  Quantities  to  the 
Conclufion,   I  (hall  only  then   make  ufe 


df  one  Infinitefimali  Suppofe  the  (Iraight 
Line  M^  cuts  the  Curve  ^  T*  in  the 
Points  2?  and  »S.  Suppofe  L2?  a  Tangent 
at  the  Point  R,  AN  the  Abfcifle,  NR 
and  OS  Ordinates.  Let  ^A''  be  produced 
to  O,  and  RP  he  drawn  parallel  to  NO. 
Suppofe  AN=x,  NR=y,  N  O  =  v, 
PS  =  %y  the  fubfecant  MN=S,  Let  the 
Equation  ^=Ar^  exprefs  the  nature  of  the 
Curve:  and  fuppofing  y  and  iV  increafed 
by  their  finite  Increments,  we  get  y  -\-  z 
^^^x-^  2y;v\-vvi  whence  the  former 
P  3  Eq^ua-. 


?7 


The   Analyst. 

Equation  being  fubdudbed  there  remains 
Z=2xv+vv.  And  by  reafon  of  fimilar 
Triangles   PS:  PR::    NR:    NM,    i.e. 

z  :v  :: y:  j  =  — >  wherein  if  for y  and  z 

we  fubflitute  their  values,  we  get  —'"\^  — 
==j=— ^.  And  fuppofins;  NO   to  be 

infinitely  diminiflied,  the  fubfecant  NM 
will  in  that  cafe  coincide  with  the  fubtan- 
gent  NL,  and  v  as  an  Infinitefimal  may 
be    rejedted,     whence     it     follows     that 

S  =  NL  =  —  =  -  5    which  is  the  true  va- 

2  AT        .2 

lue  of  the  Subtangent.  And  fince  this  was 
obtained  by  one  only  error,  /.  e.  by  once 
rejecting  one  only  Infinitefimal,  it  fhould 
feem,  contrary  to  what  hath  been  faid,that 
an  infinitefimal  Quantity  or  Difference 
may  be  negledted  or  thrown  away,  and  the 
Conclufion  neverthelefs  be  accurately  true, 
although  there  was  no  double  miftake  or 
ledifying  of  one  error  by  another,  as  in 
the  firft  Cafe.  But  if  this  Point  be  through- 
ly confidered,  we  {hall  find  there  is  even 
here  a  double  miftake,  and  that  one  com- 
penfates   or  reftifics  the  other.  For  in  the 

firft 


T  H  E     A  N  A  L  Y  S  T.  5  P 

iirfl:  plaee,    it  was   fuppofed,    that  when 
NO  is  infinitely  diminifhed  or  becomes  an, 
Infinitefimal,  then  the  Subfecant  NM  be- 
comes equal   to  the  Subtangent  NL.  But 
this   is  a  plain  miftake,  for  it  is  evident, 
that  as  a  Secant  cannot  be  a  Tangent,  fo  a 
Subfecant  cannot  be  a  Subtangent.    Be  the 
Difference  ever  fo  fmall,    yet  ftill  there  is  a 
Difference.  And  if  NO  be  infinitely  fmall, 
there  will  even  then  be  an  infinitely  fmall 
Diflference  between  NM  and  NL,  There- 
fore NM  or  S  was  too  little  for  your  fup- 
pofition,  (when  you  fuppofed  it  equal  to. 
N L)  and  this  error  was  compen fated  by  a 
fecond  error   in   throwing   out  i;,    which 
lafl  error  made  s  bigger  than  its  true  va- 
lue, and  in  lieu  thereof  gave  the  value  of 
the  Subtangent.  This  is  the  true  State  of 
the   Cafe,    however  it  may  be  difguifcd. 
And  to  this  in  reality  it  amounts,    and  is 
at  bottom  the  fame  thing,    if  we  fliould 
pretend    to  find  the  Subtangent  by  hav- 
ing   firft   found,    from   the  Equation  of 
the  Curve  and    fimilar  Triangles,    a  gcr 
neral   Expreffion   for   all  Subfecants,    and  , 
then  reducing   the  Subtangent   under  this 
general    Rule,  by  confidering    it    as   the 
P  4  Subfe- 


40  T  H  B     A  Ijl  A  L  y  $  T. 

Subfecant  when  v  vanijthcs    or  becomes 
nothing. 

XXV.  Upon  the  whole  I  obferve,  Firjf^ 
that  V  can  never  be  nothing  fo  long  a& 
there  is  a  fecant.  Secondly^  That  the  fame 
Line  cannot  be  both  tangent  and  fecant. 
thirdly,  that  when  v  or  NO  *  vanifheth, 
PS  and  iS-R  do  alfo  vanifh,  and  with 
them  the  proportionality  of  the  fimilar 
Triangles.  Confequently  the  whole  Expref- 
fion,  which  was  obtained  by  means  thereof; 
and  grounded  thereupon,  vanifheth  whea 
V  vanifheth.  Fourthly^  that  the  Method, 
for  finding  Secants  or  the  Expreffion  of  Se- 
cants, be  it  ever  fo  general,  cannot  in  com- 
mon fenfe  extend  any  further  than  to  alls 
Secants  whatfoever:  and,  as  it  neceffarily 
fuppofeth  fimilar  Triangles,  it  cannot  be 
fuppofed  to  take  place  where  there  are  not 
fimilar  Triangles.  Fifthly ^  that  the  Subfe- 
cant will  always  be  lefs  than  the  Subtaa^ 
gent,  and  can  never  coincide  with  it; 
which  Coincidence  to  fuppofe  would  be 
abfurd  J  for  it  would  be  fuppofing,  the 
fame  Line  at  the  fame    time  to  cut  and. 

*  S(e  the  foregoing  Figure, 

not 


T  HE     A  N  A  L  Y  S  T.  41 

not  to  cut  another  given  Line,  which  is  a 
manifeft  Contradicftion,  fuch  as  fubverts 
the  Hypothefis  and  gives  a  Demonftration 
of  its  Falfhood.  Sixthly,  If  this  be  not 
admitted,  I  demand  a  Reafon  why  any 
other  apagogical  Demonftration,  or  De- 
monflxation  ad  abfurdum  fhould  be  ad- 
mitted in  Geometry  rather  than  this :  Or 
that  fome  real  Difference  be  affigned  be- 
tween this  and  others  as  fuch.  Seventhly, 
I  obferve  that  it  is  fophiftical  to  fuppofe 
NO  or  RF,  PS,  znd  SR  to  be  finite 
real  Lines  in  order  to  form  the  Triangle 
UPS,  in  order  to  obtain  Proportions  by 
fimilar  Triangles ;  and  afterwards  to  fup- 
pofe there  are  no  fuch  Lines,  nor  confe- 
quently  fimilar  Triangles,  and  neverthe- 
lefs  to  retain  the  Confequence  of  the  firft 
Suppofition,  after  fuch  Suppofition  hath 
been  deftroyed  by  a  contrary  one.  Eighthly, 
That  although,  in  the  prefent  cafe,  by  in- 
confiftent  Suppofitions  Truth  may  be  ob- 
tained, yet  that  fuch  Truth  is  not  demon- 
ftrated:  That  fuch  Method  is  not  conform- 
able to  the  Rules  of  Logic  and  right  Rea- 
fon :  That,  however  ufeful  it  may  be,  it 
muft  be  confidered  only  as  a  Prefumptior, 

as 


43L  T  H    E      A  N  A  L  Y  S  T. 

as  a  Knack,  an  Arc  or  rather  an  Artifice, 
but  not  a  fcientific  Demonftration. 

XXVI.  The  Dodrine  premifed  may  be 
farther  illuftrated  by  the  following  fimple 
and  eafy  Cafe,  wherein  I  (hall  proceed  by 
evanefcent  Increments.     Suppofe  jiB  =  Xj 


FH 


BC=yy  BD  =  Oy  and  that  xx  is  equal  ta 
the  Area  ABC  :  It  is  propofed  to  find  the 
Ordinate  ^  or  BC,  When  x  by  flowing 
becomes  x  +  o,  then  x  x  becomes  xx-{- 
2XO'\-oo:  And  the  Area  ABC  becomes 
ADH,  and  the  Increment  of  xx  will  be 
equal  to  BDHC  the  Incremem  of  the 

Area. 


-T  H  E      A  N  A  L  Y  S  T.  4.J 

Area,  I  e.  to  BCFD+CFH.  And  If 
we  fuppofe  the  curvilinear  Space  C  FH  to 
he  go  0,  then  2x0  -i-oo  =y  o-\-  qoo  which 
xlividedby  0  gives  2^:4-0  =^4- §'(?.  And, 
fuppofing  0  to  vanifli,  2x=y,  in  which 
Cafe  ACH  will  be  a  ftraight  Line,  and 
the  Areas  ^BC,  CFH,  Triangles.  Now 
with  regard  to  this  Reafoning,  it  hath 
been  already  remarked  *,  that  it  is  not  le- 
gitimate or  logical  to  fuppofe  0  to  vanifh, 
/.  e,  to  be  nothing,  /.  e.  that  there  is  no 
Increment,  unlefs  we  rejedt  at  the  fame 
time  with  the  Increment  it  felf  every  Con- 
fequence  of  fuch  Increment,  /.  e.  what- 
foever  could  not  be  obtained  but  by  fup- 
pofing fuch  Increment.  It  mufl  never- 
thelefs  be  acknowledged,  that  the  Problem 
is  rightly  folved,  and  the  Conclufion  true, 
to  which  we  are  led  by  this  Method.  It 
will  therefore  be  asked,  how  comes  it  to 
pafs  that  the  throwing  out  0  is  attended 
with  no  Error  in  the  Conclufion  }  I  an- 
fwer,  the  true  reafon  hereof  is  plainly 
thi5:  Becaufe  q  being  Unite,  qo  \s  equal 
to  o\  And  therefore  zx-\-o — qo=:y^=2Xy 

*  Se^.   12  and  i^,  fupra. 

the 


44  T  H  E     A  N  A  L  Y  S  t. 

the  equal  Quantities  qo  and  o  being  dci* 
ftroyed  by  contrary  Signs. 

XXVIL  As  on  the  one  hand'  it  were 
abfurd  to  get  rid  of  o  by  faying,  let  mc 
contradidt  my  fclf :  Let  me  fubvert  my 
own  Hypothefis :  Let  mc  take  it  for  grant* 
ed  that  there  is  no  Increment,  at  the  fame 
time  that  I  retain  a  Quantity,  which  I 
could  never  have  got  at  but  by  afluming 
an  Increment:  So  on  the  other  hand  it 
Would  be  equally  wrong  to  imagine,  that 
in  a  geometrical  Dcmonftration  we  may 
be  allowed  to  admit  any  Error,  though 
ever  fo  fmall,  or  that  it  is  poffible,  in  the 
nature  of  Things,  an  accurate  Conclufion 
fliould  be  derived  from  inaccurate  Prin^ 
ciples.  Therefore  a  cannot  be  thrown  out 
as  an  Infinitefimal,  or  upon  the  Principle 
that  Infinitefimals  may  be  fafely  negleded. 
But  only  becaufe  it  is  deftroyed  by  an 
equal  Quantity  with  a  negative  Sign, 
whence  o^^qo  is  equal  to  nothing.  And 
as  it  is  illegitimate  to  reduce  an  Equation, 
by  fubduding  from  one  Side  a  Quantity 
when  it  is  not  to  be  deftroyed,  or  when 
an  equal  Quantity  is  not  fubduilcd  from 

the 


The   A  N  A  L  Y  s  T.  45 

i;he  other  Side  of  the  Equation :  So  it  mufl: 
be  allowed  a  very  logical  and  juft  Method 
of  arguing,  to  conclude  that  if  from  E- 
qual«  either  nothing  or  equal  Quantities 
are  fubdu<fted,  they  fhall  ftill  remain  equal. 
And  this  is  a  true  Reafon  why  no  Error 
js  at  laft  produced  by  the  rejecting  of  o. 
Which  therefore  muft  not  be  afcribed  to 
the  Dodtrine  of  Differences,  or  Infinitefi- 
mals,  or  evancfcent  Quantities,  or  Mo- 
mentums,  or  Fluxions. 

XXVni.  Suppofe  the  Cafe  to  be  gene- 
ral, and  that  ;c«  is  equal  to  the  Area 
ABC^  whence  by  the  Method  of  Fluxi- 
ons the  Ordinate  is  found  nx^-^^  which 
we  admit  for  true,  and  (hall  inquire  how 
it  is  arrived  at.  Now  if  we  are  content 
to  come  at  the  Conclufion  in  a  fummary 
way,  by  fuppofing  that  the  Ratio  of  the 
Fluxions  of  x  and  x»  are  found  *  to  be 
I  and  «a:»— ',  and  that  the  Ordinate  of 
the  Area  is  coniidcred  as  its  Fluxion  ;  wc 
fliall  not  fo  clearly  fee  our  way,  or  per- 
ceive how  the  truth  comes  out,  that  Me- 
thod as  we  have  fticwed  before  being  ob- 

*  s,a.  13. 

fcure 


4(5  /.T^H  E    Analyst. 

fcure  and  illogical.  But  if  we  fairly  de^ 
lineate  the  Area  and  its  Increment,  and 
divide  the  latter  into  two  Parts  BCFD 
and  C  FH^y  and  proceed  regularly  by  E- 
quatlons  between  the  algebraical  and  geo- 
metrical Quantities,  the  rcafon  of  the 
thing  will  plainly  appear.  For  as  a:  «  is 
equal  to  the  Area  AB  C^  fo  is  the  In- 
crement of  ^«  equal  to  the  Increment 
pf  the  Area^  /.  e.  to  BDHG-,  that  is^ 
to  fay,  «o:v«  — I  +/-^-^ o o  at » -  ^  4-  ^c. 

==BDFC  4-  CFH.  And  only  the  firft 
Members,  on  each  Side  of  the  Equation 
being  retained,  nox*"--^  =BDFC:  And 
dividing  both  Sides  by  <?  or  B  D,  we 
fliall  get  nx»  —  ^=BC.  Admitting, 
therefore,  that  the  curvilinear  Space  CFH 
is    equal   to    the    rejedaneous    Quantity 

VLTU^oox^-^  +  &c.   and  that  when  this 

2 

is  rejected  on  one  Side^  that  is  rcjedled  on 
the  other,  the  Reafoning  becomes  juft  and 
the  Conclufion  true.  And  it  is  all  one 
whatever  Magnitude  you  allow  to  B  D^ 
whether  that  of  an  infinitefimal  Difference 
or  a  finite  Increment  ever  fo  great.  It  is  there- 
fore plain,  that  the  fuppofing  the  rejectaneous 

*  See  tie  Figure  in  Sea.  z6.  alge- 


T  H  E     A  K  A  L  Y  S   T.  47 

algebraical  Quantity  to  be  an  infinitely 
fmall  or  evanefcent  Quantity,  and  there- 
fore to  be  negleded,  muft  have  produced 
an  Error,  had  it  not  been  for  the  curvi- 
linear Spaces  being  equal  thereto,  and  at 
the  fame  time  fubduded  from  the  other 
Part  or  Side  of  the  Equation  agreeably  to 
the  Axiom,  If  from  Equals  you  fubdudl 
Equals^  the  Remainders  ivill  be  equal  For 
thofe  Quantities  which  by  the  Analyfts  are 
faid  to  be  neglected,  or  made  to  vanifli, 
are  in  reality  fubduded.  If  therefore  the 
Conclufion  be  true,  it  is  abfolutely  necef- 
iary  that  the  finite  Space  C  F  H  he  equal 
to    the     Remainder     of    the    Increment 

expreffed  by  ^"'"•"•oox^  —  ^  &c.  equal  I  fay 

to  the  finite  Remainder  of  a  finite  Incre- 
ment. 

XXIX.  Therefore,  be  the  Power  what 
you  pleafe,  there  will  arife  on  one  Side 
an  algebraical  Exprefllon,  on  the  other  a 
geometrical  Quantity,  each  of  which  na- 
turally divides  it  felf  into  three  Members: 
The  algebraical  or  fluxionary  Exprefllon, 
into  one  which  includes  neither  the  Ex- 
prefllon 


4>  T  H  E     A  N  A  L  Y  S  T. 

preflion  of  the  Increment  of  the  Abfcifs 
nor  of  any  Power  thereof,  another  which 
includes  the  Expreflion  of  the  Increment 
it  felf,  and  a  third  including  the  Expref- 
fion  of  the  Powers  of  the  Increment.  The 
geometrical  Quantity   alfo   or   whole  in- 
creafed  Area  confifls   of  three    Parts    or 
Members,  the  firft  of  which  is  the  given 
Area,  the  fecond   a  Redtangle  under  the 
Ordinate   and  the  Increment  of  the  Ab- 
fcifs, and  the  third  a   curvilinear   Space, 
And,  comparing  the  homologous  or  cor- 
refpondent  Members  on  both  Sides,    we 
find  that  as  the  firft  Member  of  the  Ex-r 
preflion    is   the   Expreflion  of  the  given 
Area,  fo  the  fecond  Member  of  the  Ex- 
preflion will  exprefs  the  Re(flangle   or  fe- 
cond Member  of  the  geometrical  Quanti- 
ty ;  and  the  third,  containing  the  Powers 
of  the  Increment,  will  exprefs  the  curvi- 
linear Space,  or  third  Member  of  the  geo- 
metrical Quantity.     This  hint  may,  per- 
haps, be  further  extended  and  applied  to 
good  purpofe,  by  thofe  who  have  leifurc 
and  curiofiry  for  fuch  Matters.     The  ufe 
I  make  of  it  is  to  fliew,  that  the  Analyfis 
cannot  obtain  in  Augments  or  DiiFerences, 

but 


T  H  E     A  N  A  L  Y  S  t.  45> 

but  it  muft  alfo  obtain  in  finite  Quantities, 
be  they  ever  fo  great,  as  was  before  ob- 
ferved. 

XXX.  It  fecms  therefore  upon  the 
whole  that  we  may  fafely  pronounce,  the 
Conclufion  cannot  be  right,  if  in  order 
thereto  any  Quantity  be  made  to  vanifli, 
or  be  negledled,  except  that  either  one 
Error  is  redrefled  by  another ;  or  that  fe- 
condlyj  on  the  fame  Side  of  an  Equa- 
tion equal  Quantities  are  deftroycd  by 
contrary  Signs,  fo  that  the  Quantity  wc 
mean  to  rejcd:  is  firfl  annihilated  3  or 
laftly,  that  from  the  oppofite  Sides  equal 
Qu^antities  are  fubducled.  And  therefore 
to  get  rid  of  Quantities  by  the  received 
Principles  of  Fluxions  or  of  Differences  is 
neither  good  Geometry  nor  good  Logic. 
When  the  Augments  vanifli,  the  Veloci- 
ties alfo  vaniCh.  The  Velocities  or  Fluxi- 
ons are  faid  to  h^  primo  and  ulfimo,  as  the 
Augments  nafcent  and  evanefcent.  Take 
therefore  the  Ratio  of  the  evanefcent 
Quantities,  it  is  the  Tame  with  that  of 
the  Fluxions.  It  will  therefore  anfwer  all 
Intents  as  well.  Why  then  are  Fluxions 
E  intro* 


5©  The    Analyst. 

introduced?  Is  it  not  to  fliun  or  rather 
to  palliate  the  Ufe  of  Quantities  infinitely 
fmall  ?  But  we  have  no  Notion  whereby 
to  conceive  and  meafure  various  '  Degrees 
of  Velocity,  befide  Space  and  Time,  or 
when  the  Times  are  given,  befide  Space 
alone.  We  have  even  no  Notion  of  Ve- 
locity prefcinded  from  Time  and  Space. 
,  When  therefore  a  Point  is  fuppofed  to 
move  in  given  Times,  we  have  no  Notion 
of  greater  or  lefler  Velocities  or  of  Pro- 
portions between  Velocities,  but  only  of 
longer  or  (horter  Lines,  and  of  Proporti- 
ons between  fuch  Lines  generated  in  equal 
Parts  of  Time. 

XXXL  A  Point  maybe  the  limit  of  a 
Line :  A  Line  may  be  the  limit  of  a  Sur- 
face: A  Moment  may  terminate  Time. 
But  how  can  we  conceive  a  Velocity  by 
the  help  of  fuch  Limits  ?  It  neceflarily  im- 
plies both  Time  and  Space,  and  cannot 
be  conceived  without  them.  And  if  the 
Velocities  of  nafcent  and  evanefcent  Quan- 
tities, /.  e,  abftraded  from  Time  and 
Space,  may  not  be  comprehended,  how 
can  we  comprehend  and  demonflrate  their 

Propor- 


The    Analyst.  fi 

Proportions  ?  Or  confider  their  rationes 
frimce  and  ultima.  For  to  confider  the 
Proportion  or  Ratio  of  Things  implies  that 
fuch  Things  have  Magnitude :  That  fuch 
their  Magnitudes  may  be  meafijred,  and 
their  Relations  to  each  other  known.  But, 
as  there  is  no  meafurc  of  Velocity  except 
Time  and  Space,  the  Proportion  of  Velo- 
cities being  only  compounded  of  the  di- 
red  Proportion  of  the  Spaces,  and  the 
reciprocal  Proportion  of  the  Times ;  doth 
it  not  follow  that  to  talk  of  inveftigating, 
obtaining,  and  confidering  the  Proportions 
of  Velocities,  exclufively  of  Time  and 
Space,  is  to  talk  unintelligibly  ? 

XXXII.  But  you  will  fay  that,  in  the 
ufe  and  application  of  Fluxions,  Men  do 
not  overftrain  their  Faculties  to  a  precife 
Conception  of  the  abovementioned  Velo- 
cities, Increments,  Infinitefimals,  or  any 
other  fuch  like  Ideas  of  a  Nature  fo  nice, 
fubtile,  and  evanefcent.  And  therefore 
you  will  perhaps  maintain,  that  Problems 
may  be  folved  without  thofe  inconceiva- 
ble Suppofitions:  and  that,  confequently, 
the  Dodlrin^  of  Fluxions,  as  to  the  prac- 

E  2  tical 


The    Analyst. 

tical  Part,  ftands  clear  of  all  fuch  Diffi- 
culties. I  anfwer,  that  if  in  the  ufe  or 
application  of  this  Method,  thofe  difficult 
and  obfcure  Points  are  not  attended  to^ 
they  are  neverthelefs  fuppofed.  They  are 
the  Foundations  on  which  the  Moderns 
build,  the  Principles  on  which  they  pro- 
ceed, in  folving  Problems  and  difeover- 
ing  Theorems.  It  is  with  the  Method  of 
Fluxions  as  with  all  other  Methods,  which 
prefuppofe  their  refpedlive  Principles  and 
are  grounded  thereon.  Although  the 
Rules  may  be  pradifed  by  Men  who  nei- 
ther attend  to,  nor  perhaps  know  the 
Principles.  In  like  manner,  therefore,  as 
a  Sailor  may  practically  apply  certain 
•Rules  derived  from  Aflronomy  and  Geo- 
metry, the  Principles  whereof  he  doth 
not  underftand :  And  as  any  ordinary  Man 
m:ay  folve  divers  numerical  Queftions,  by 
the  vulgar  Rules -and  Operations  of  Arith- 
metic, which  he  performs  and  applies 
without  knowing  the  Reafons  of  them: 
Even  fo  it  cannot  be  denied  that  you  may 
apply  the  Rules  of  the  fluxionary  Me- 
thod :  You  may  compare  and  reduce  par- 
ticular Cafes  to  general  Forms :  You  may 

operate 


w 


TheAnalyst.  5} 

operate  and  compute  and  folve  Problems 
thereby,  not  only  without  an  adual  At- 
tention to,  or  an  adlual  Knowledge  of,  the 
Grounds  of  that  Method,  and  the  Prin- 
ciples whereon  it  depends,  and  whence  it 
is  deduced,  but  even  without  having  ever 
confidered  or  comprehended  them. 

XXXIII.  But  then  it  muft  be  remembred, 
that  in  fuch  Cafe  although  you  may  paf^ 
for  an  Artift,  Computift,  or  Analyft,  yet 
you  may  not  be  juftly  efteemed  a  Man  of 
Science  and  Demonflration.  Nor  fliould 
any  Man,  in  virtue  of  being  converfanc 
in  fuch  obfcure  Analytics,  imagine  his 
rational  Faculties  to  be  more  improved 
than  thofe  of  other  Men,  which  have 
been  exercifed  in  a  difterent  manner,  and 
on  different  Subjefts  ;  much  lefs  ered:  him- 
felf  into  a  Judge  and  an  Oracle,  concern- 
ing Matters  that  have  no  fort  of  conne- 
xion with,  or  dependence  on  thofe  Species, 
Symbols  or  Signs,  in.  the  Management 
whereof  he  is  fo  converfant  and  expert. 
As  you,  who  are  a  skilful  Computift  or 
Analyft,  may  not  therefore  be  deemed 
skilful  in  Anatomy :  or*  vice  verja,  as  a 
E  3  Mm 


54  TheAnalyst. 

Man  who  can  diffedl  with  Art,  may,  nc- 
verthclefs,  be  ignorant  in  yoqr  Art  of  com- 
puting :  Even  fo  you  may  both,  notwith- 
^  {landing  your  peculiar   Skill  in  your   re- 

fpedtive  Arts,  be  alike  unqualified  to  de- 
cide upon  Logic,  or  Metaphyfics,  or  E- 
thics,  or  Religion.  And  this  would  be 
true,  even  admitting  that  you  underftood 
your  own  Principles  and  could  demon- 
ftrate  them. 

XXXIV.  If  it  IS  faid,  that  Fluxions 
may  be  expounded  or  expreffed  by  finite 
Lines  proportional  to  them  :  Which  finite 
Lines,  as  they  may  be  diftindtly  conceiv- 
ed and  known  and  reafoned  upon,  fo  they 
may  be  fubftituted  for  the  Fluxions,  and 
their  mutual  Relations  or  Proportions  be 
confidered  as  the  Proportions  of  Fluxions : 
By  which  means  the  Doctrine  becomes 
clear  and  ufeful.  I  anfwer  that  if,  in  or- 
der to  arrive  at  thefe  finite  Lines  propor- 
tional to  the  Fluxions,  there  be  certain 
Steps  made  ufe  of  which  are  obfcure  and 
inconceivable,  be  thofe  finite  Lines  them- 
felves  ever  fo  clearly  conceived,  it  muft 
neverthelefs  be  "acknowledged,  that  your 

proceed- 


IHP      The   Analyst. 

proceeding  is  not  clear  nor  your  method 
fcientific.  For  inftance,  it  is  fuppofed  that 
4B  being  the  Abfcifs,  B  C  the  Ordinate, 


55 


and  VCH  2i  Tangent  of  the  Curve  AC, 
Bb  ov  CE  the  Increment  of  the  Abfcifs, 
Ec  the  Increment  of  the  Ordinate,  which 
produced  meets  V  H  \n  the  Point  T*, 
and  Cc  the  Increment  qf  the  Curve.  The 
right  Line  C  c  being  produced  to  K,  there 
are  formed  three  fmall  Triangles,  the 
Redilinear  CEc,  the  Mixtilinear  CEc, 
and  the  ReftiUnear  Triangle  GET.  It 
is  evident  thefe  three  Triangles  are  dif- 
ferent from  each  other,  the  Redilinear 
C  E  c  being  lefs  than  the  Mixtilinear 
CEc,  whofe  Sides  are  the  three  Incre- 
ments abovementioned,  and  this  ftill  lefs 
^han  the  Triangle  GET.  It  is  fuppofed 
that  the  Ordinate  b  c  moves  into  the  place 
BC,  fo  that  the  Point  c  is  coincident  with 
the'  Point  C^  and  the  right  Line  C  K 
E  4.  an4 


5(>  Thi    Analyst. 

and  confequently  the  Curve  Cr,  is  coin-' 
cident  with  the  Tangent  C  H.  In  which 
cafe  the  mixtilinear  evanefcent  Triangle 
CE  c  will,  in  its  laft  form,  be  fimilar  to 
the  Triangle  GET:  And  its  evanefcent 
Sides  C  E,  E  f ,  and  C  c  will  be  porpor- 
tional  to  CE^  ET,  and  CtT  the  Sides  of 
the  Triangle  C  E  T,  And  therefore  it 
is  concluded,  that  the  Fluxions  of  the 
Lines  j4B,  BC,  and  AC,  being  in  the 
»  laft  Ratio  of  their  evanefcent  Increments, 
are  proportional  to  the  Sides  of  the  Tri- 
angle GET,  or,  which  is  all  one,  of  the 
Triangle  V  B  G  fimilar  thereunto,  *  It 
it  particularly  remarked  and  infifted  on 
by  the  great  Author,  that  the  Points  C 
and  c  muft  not  be  diftant  one  from  ano- 
ther, by  any  the  leaft  Interval  whatfoever; 
But  that,  in  order  to  find  the  ultimate 
Proportions  of  the  Lines  C  E,  E  c,  and 
C  c  (/.  e,  the  Proportions  of  the  Fluxi- 
ons or  Velocities)  expreffed  by  the  finite 
Sides  of  the  Triangle  FBG,  the  Points  C 
and  c  muft  be  accurately  coincident,  i,  e. 
one  and  the  fame.  A  Point  therefore  is 
confidered  as  a  Triangle,  or  a  Triangle  is 
iuppofed  to  be  formed  in  a  Point,     Whicjn 

^  Introdud.  ad  Quad.  Cur  v.  tO 


^  TheAnalyst.  57 

to  conceive  feems  quite  impoffible.  Yet 
fome  there  are,  who,  though  they  (hrink  at 
all  other  Myfteries,  make  no  difficulty  of 
their  own,  who  ilrain  at  a  Gnat  and  fwal- 
low  a  Camel. 

XXXV.  I  know  not  whether  it  be 
worth  while  to  obferve,  that  poffibly  fome 
Men  may  hope  to  operate  by  Symbols 
and  Suppofitions,  in  fuch  fort  as  to  avoid 
the  ufe  of  Fluxions,  Momentums,  andln- 
finitefimals  after  the  following  manner. 
Suppofe  X  to  be  one  Abfcifs  of  a  Curve, 
and  z  another  Abfcifs  of  the  fame  Curve. 
Suppofe  alfo  that  the  refpe6tive  Areas  are 
XXX  2indizzz:  and  that  z* — x  is  the  In- 
crement of  the  Abfcifs,  and  zzz  —  xx x 
the  Increment  of  the  Area,  without  confi- 
dering  how  great,  or  how  fmall  thofe  In- 
crements may  be.  Divide  nov^zzz  —  xx  x 
by  2J  —  AT  and  the  Quotient  will  be 
zz  '\-  z  x-]r  X  X  :  and,  fuppofing  that 
z  and  X  are  equal,  this  fame  Quotient  will 
be  3  ;^  X  which  in  that  cafe  is  the  Ordinate, 
which  therefore  may  be  thus  obtained  in- 
dependently of  Fluxions  and  Infinitefi- 
•mals.  But  herein  is  a  diredt  Fallacy:    for 

in 


5g  The    Analyst. 

in  the  firft  place,  it  is  fuppofed  that  the 
Abfcifles  z  and  x  are  unequal,  without 
which  fuppofition  no  one  ftep  could  have 
been  made  ;  and  in  the  fecond  place,  it  is 
fuppofed  they  are  equal  ^  which  is  a  mani- 
feft  Inconfiftency,  and  amounts  to  the 
fame  thing  that  hath  been  before  confi- 
dered  *  And  there  is  indeed  reafon  to  ap- 
prehend, that  all  Attempts  for  fetting  the 
abftrufe  and  fine  Geometry  on  a  right 
Foundation,  and  avoiding  the  Dodrine  of 
Velocities,  Momentums,  &c,  will  be 
found  impradlicable,  till  fuch  time  as  the 
Objed:  and  End  of  Geometry  are  better  un- 
derftood,  than  hitherto  they  feem  to  have 
been.  The  great  Author  of  the  Method 
of  Fluxions  felt  this  Difficulty,  and  there- 
fore he  gave  into  thofe  nice  Abftradions 
and  Geometrical  Metaphyfics,  without 
which  he  faw  nothing  could  be  done  on 
the  received  Principles  ;  and  what  in  the 
way  of  Demonftration  he  hath  done  with 
them  the  Reader  will  judge.  It  muft,  in- 
deed, be  acknowledged,  that  he  ufed 
Fluxions,  like  the  Scaffold  of  a  building, 
as  things  to  be  laid  afide  or  got  rid  of,  as 
'     foon  as  finite  Lines  were  found  proportion 

•  Sea.  15.         ' '  ^^^ 


p  The    Analyst.  59 

nal  to  them.  But  then  thefe  finite  Expo- 
nents are  found  by  the  help  of  Fluxions. 
Whatever  therefore  is  got  by  fuch  Expo- 
nents and  Proportions  is  to  be  afcribed  to 
Fluxions:  which  mull  therefore  be  previ- 
oufly  underftood.  And  what  are  thefe 
Fluxions?  The  Velocities  of  cvanefcent 
Increments  ?  And  what  are  thefe  fame  cva- 
nefcent Increments  ?  They  are  neither  fi- 
nite Quantities,  nor  Quantities  infinitely 
fmall,  nor  yet  nothing.  May  we  not  call 
them    the    Ghofts    of  departed  Quanti*- 

lies  ? 

«• 

XXXVI.  Men  too  often  impofc  on 
themfelves  and  others,  as  if  they  conceived 
and  underftood  things  expreffed  by  Signs, 
when  in  truth  they  have  no  Idea,  fave 
only  of  the  very  Signs  themfelves.  And 
there  are  fome  grounds  to  apprehend  that 
this  may  be  the  prefent  Cafe.  The  Velo- 
cities of  evanefcent  or  nafcent  Quantities 
are  fuppofed  to  be  expreffed,  both  by  fi- 
nite Lines  of  a  determinate  Magnitude, 
and  by  Algebraical  Notes  or  Signs :  but  I 
fufpedt  that  many  who,  perhaps  never 
having  examined  the  matter,    take  it  for 

granted. 


Co  TheAnalyst. 

granted,  would  upon  a  narrow  fcrutiny 
find  it  impoffible,  to  frame  any  Idea  or 
Notion  whatfoever  of  thofe  Velocities,  ex- 
clufive  of  fuch  finite  Quantities  and  Signs. 

a  /         c  B  e 

} 1     I     I     I     ■,     !     t     I      i \ ( 

K  X'^^^"l/[/^7^]Sr  o  P 

Suppofe  the  Line  K  P  defcribed  by  the 
Motion  of  a  Point  continually  accelerated, 
and  that  in  equal  Particles  of  time  the 
unequal  Parts  KL,  LM,  MN,  NO  &e. 
are  generated.  Suppofe  alfo  that  a,  b^  c^  J,  <f, 
Gfc.  denote  the  Velocities  of  the  genera- 
ting Point,  at  the  feveral  Periods  of  the 
Parts  or  Increments  io  generated.  It  is  eafy  to 
obferve  that  thefe  Increments  are  each  pro- 
portional to  the  fum  of  the  Velocities  with 
which  it  is  defcribed :  That,  confcquently, 
the  feveral  Sums  of  the  Velocities,  generated 
in  equal  Parts  of  Time,  may  be  fet  forth 
by  the  refpedlive  Lines  KL^  LM,  MJV, 
&c.  generated  in  the  fame  times :  It  is 
likewife  an  eafy  matter  to  fay,  that  the 
laft  Velocity  generated  in  the  firft  Parti- 
cle of  Time,  may  be'  exprefTed  by  the 
Symbol  ^,  the  laft  in  the  fecond  by  i,  the 
laft  generated  in  the   third  by  f,    and  fo 

on  : 


P  Th  E     A  N  A  L  Y  S  T.  ^1 

on :  that  a  is  the  Velocity  of  L  M  in 
fiatu  nafcentiy  and  b,  c,  d,  f,  &?r.  are  the 
Velocities  of  the  Increments  MAT,  A^O, 
O  P,  Gfr.  in  their  refpedive  nafcent  eftates. 
You  may  proceed,  and  confider  thefe  Ve- 
locities themfelves  as  flowing  or  increafing 
Quantities,  taking  the  Velocities  of  the 
Velocities,  and  the  Velocities  of  the  Ve- 
locities of  the  Velocities,  /.  e,  the  firft, 
fecond,  third,  S*c.  Velocities  ad  infinitum : 
which  fucceeding  Series  of  Velocities  may 
be  thus  exprefTed.  a,  b  — a,  c  —  ib'\-  a, 
d — 3^'i"3^  —  ^  ^c,  which  you  may  call 
by  the  names  of  firft,  fecond,  third,  fourth 
Fluxions.  And  for  an  apter  Expreffion 
you  may  denote  the  variable  flowing  Line 
KL,  KM,  KN,  &c,  by  the  Letter  Xi 
and  the  firft  Fluxions  by  x,  the  fecond 
by  X,  the  third  by  x,  and  fo  on  ad  infini^ 
turn, 

XXX Vn.  Nothing  is  cafier  than  toaflign 
Names,  Signs,  or  Expreflions  to  thefe 
Fluxions,  and  it  is  not  difficult  to  compute 
and  operate  by  means  of  fuch  Signs.  But 
it  will  be  found  much  more  difficult,  to 
omit    the  Signs    and  yet    retain    in   our 

Mipds 


CZ  T  H  E     A  N  A  L  Y  S  T.^ 

Minds  the  things,    which  we  fuppofe  to 
be  fignlfied  by  them.  To  confider  the  Ex- 
ponents,   whether  Geometrical,   or  Alge- 
braical, or  Fluxionary,is  no  difficult  Mat- 
ter. But  to  form  a  precife  Idea  of  a  third 
Velocity  for  inftance,   in  it  felf  and  by  it 
felf.  Hoc  opus^  hie  labor.    Nor  indeed  is  it 
an  eafy  point,  to  form  a  clear  and  diftind 
Idea  of  any  Velocity  at  all,    exclufive  of 
and   prefcinding  from  all  length  of  time 
and  fpace ;   as  alfo  from  all   Notes,  Signs 
or  Symbols  whatfoever*    This,    if  I    may 
be  allowed  to  judge  of  others  by  my  felf, 
is  impoffible.  To  me  it  feems  evident,  that 
Meafures  and  Signs  are  abfolutely  neceffa- 
ry,  in  order  to  conceive  or   reafon   about 
Velocities ;  and  that,  confequently,    when 
we  think  to  conceive  the  Velocities,    Am- 
ply and  in  themfelves^  we  are  deluded  by 
vain  Abftraftions. 

XXXVIII.  It  may  perhaps  be  thought 
by  fome  an  eafier  Method  of  conceiving 
Fluxions,  to  fuppofe  them  the  Velocities 
wherewith  the  infinitefimal  Differences  are 
generated.  So  that  the  firft  Fluxions  fhall 
be  the  Velocities  of  the  firft  Differences, 

the 


11^         TheAnalyst.  ^3 

the  fecond  the  Velocities  of  the  fecond 
Differences,  the  third  Fluxions  the  Veloci- 
ties of  the  third  Differences,and  fo  on  adin^ 
Jinitum,  But  not  to  mention  the  infurmoun- 
table  difficulty  of  admitting  or  conceiving 
Infinitefimals,  and  Infinitefimals  of  Infinite- 
fimals,  &c,  it  is  evident  that  this  notion  of 
Fluxions  would  not  confift  with  the  great 
Author's  view  ;  who  held  that  the  minuteft 
Quantity  ought  not  to  be  negled:ed,  that 
therefore  the  Do<flrine  of  Infinitefimal  Diffe- 
rences was  not  to  be  admitted  in  Geome- 
try, and  who  plainly  appears  to  have  in- 
troduced the  ufe  of  Velocities  or  Fluxions, 
onpurpofc  to  exclude  or  do  without  them. 

XXXIX.  To  others  it  may  poffibly 
feem,  that  we  fhould  form  a  jufter  Idea  of 
Fluxions,  by  affuming  the  finite  unequal 
ifochronal  Increments  KL,  LM,  MN,  &c. 
and  confidering  them  mjiatu  nafcenti^  alfo 
their  Increments  in  Jlatu  nafcenti,  and  the 
nafcent  Increments  of  thofe  Increments, 
and  fo  on,  fuppofing  the  firft  nafcent  In- 
crements to  be  proportional  to  the  firft 
Fluxions  or  Velocities,  the  nafcent  Incre- 
ments of  thofe  Increments  to  be  propor- 
tional 


4^4  T  H  E     A  N  A  L  Y  S  t. 

tional  to  the  fecond  Fluxions,  the  third 
nafcent  Increments  to  be  proportional  to 
the  third  Fluxions,  and  fo  onwards.  And, 
as  the  firft  Fluxions  are  the  Velocities  of 
the  firft  nafcent  Increments,  fo  the  fe- 
cond Fluxions  may  be  conceived  to  be  the 
Velocities  of  the  fecond  nafcent  Incre- 
ments, rather  than  the  Velocities  of  Ve- 
locities. By  which  means  the  Analogy  of 
Fluxions  may  feem  better  preferved,  and 
the  notion  rendered  more  intelligible. 

XL.  And  indeed  it  fhould  feem,  that 
in  the  way  of  obtaining  the  fecond  or 
third  Fluxion  of  an  Equation,  the  given 
Fluxions  were  confidered  rather  as  Incre- 
ments than  Velocities.  But  the  confider- 
ing  them  fometimes  in  one  Senfc,  fome- 
times  in  another,  one  while  in  themfelves, 
another  in  their  Exponents,  feems  to  have 
occafioned  no  fmall  fhare  of  that  Confu- 
fion  and  Obfcurity,  which  is  found  in  the 
Dodlrine  of  Fluxions.  It  may  feem  there-^ 
fore,  that  the  Notion  might  be  ftill  mend* 
ed,  and  that  inftead  of  Fluxions  of  Fluxi- 
ons, or  Fluxions  of  Fluxions  of  Fluxions, 
and  inftead  of  fecond,  third,  or  fourth^G^r. 

Fluxions 


T  H  E     A  N  A  L  Y  S  T.  ^5 

Fluxions  of  a  given  Quantity,    it  might  be. 
more  confiftent  and  lefs  liable  tocxception* 
to  fay,    the  Fluxion  of  vthe  firft  nafcenti 
Increment,  i,  e.  the  fecond  Fluxion ;  the 
Fluxion  of  the  fecond  nafcent  Increment,^ 
i.  e,  the   third  Fluxion  ;    the  Fluxion  ofi 
the   third    nafcent    Increment,    /.  f-    the. 
fourth  Fluxion,  which  Fluxions  are  con- 
ceived  refped:ively   proportional,    each  to. 
the  nafcent   Principle   of    the    Increment 
fuccecding  that  whereof  it  is  the  Fluxion.  ^ 

XLI.  For  the  more  diftindt  Conception* 
of  all  which  it  may  be  confidered,  that  if 
the  finite  Increment  LM*be  divided  into* 
the  Ifochronal  Parts    L niy   ?n n,  no,  o M-, 
and  the  Increment    MN  into   th^, Parts 
Mp,  pqy  qr,  rN  Ifochronal  to  the  for-, 
mer  -,  as  the  whole  Increments  L  M,  MN* 
are  proportional  to  the   Sums  of  their  dc-' 
fcribing  Velocities,    even  fo  the   homolo-' 
gous  Particles  L  m,  Mp  are  alfo   propor- 
tional to  the  refpedtive  accelerated  Veloci-  * 
ties  with  which  they   are  defer ibed.   And' 
as  the  Velocity  with  which  Mp  is  gene-' 
rated,  exceeds  that  with  which  Lj?2  was 
generated,    even  fo  the   Particle  Mp  ex- 

*  See  the  foregiing  Scheme  in  Se£i.  36. 

F  ceeds 


6d  The    Analyst, 

cceds  the  Particle  Lm.  And  in  general, 
as  the  Ifoehronal  Velocities  dcfcribing  the 
Particles  of  MN  exceed  the  Ifoehronal 
Velocities  defcribing  the  Particles  of  L  Af> 
even  fo  the  Particles  of  the  farmer  e^^ceed 
the  correfpondent  Particles  of  the  latter. 
And  this  will  hold,  be  the  faid  Particles 
ever  fo  fmall.  MN  therefore  will  exceed 
J/  M  if  they  are  both  taken  in  their  naf- 
cent  States :  and  that  excefs  will  be  pro- 
portional to  the  excefs  of  the  Velocity  b 
above  the  Velocity  a.  Hence  we  may  fee 
that  this  laft  account  of  Fluxions  comes, 
in  the  upfliot,  to  the  f^me  thing  with 
the  firft  *. 

XLII.  But  notwithftanding  what  hath 
been  faid  it  muft  ftill  be  acknowledged, 
that  the  finite  Particles  L  m  or  Af /», 
though  taken  ever  fo  fmall,  are  not  pro- 
portional to  the  Velocities  a  and  i ;  but 
each  to  a  Series  of  Velocities  changing 
every  Moment,  or  which  is  the  fame  thing, 
to  an  accelerated  Velocity,  by  which  it  is 
generated,  during  a  certain  minute  Parti-, 
cle  of  time :  That  the  nafcent  beginnings 
or  evanefcent  endings  of  finite  Quantities^ 

♦  Sf£i.  36  which 


TheAnalyst:  cy 

which  are  produced  in  Moments  or  .inft- 
nitely  fmall  Parts  of  Tin>e,  are  alone 
proportional  to  given  Velocities:  That, 
therefore,  in  order  to  conceive  the  firft 
Fluxions,  we  muft  conceive  Time  divi- 
ded into  Moments,  Increments  generated 
in  thofe  Moments,  and  Velocities  propor- 
tional to  thofe  Increments  :  That  in  order 
to  conc«ive  fecond  and  third  Fluxions,  v^^e 
muft  fuppofe  that  the  nafcent  Principles  or 
momentaneous  Increments  have  themfelves 
alfo  other  momentaneous  Increments,  w^hich 
are  proportional  to  their  refped:ive  genera- 
ting Velocities:  That  the  Velocities  of 
thefe  fecond  momentaneous  Increments  are 
fecond  Fluxions:  thofe  of  their  nafcent 
momentaneous  Increments  third  Fluxions, 
And  fo  on  ad  infinitum, 

XLIII.  By  fubdudling  the  Increment 
generated  in  the  firft  Moment  from  that 
generated  in  the  fecond,  we  get  the  Incre- 
ment of  an  Increment.  And  by  fubdudt- 
ing  the  Velocity  generating  in  the  firft  Mo- 
ment from  that  generating  in  the  fecond, 
we  get  the  Fluxion  of  a  Fluxion.  In  like 
manner,  by  fubduding  the  Difference  of 

F  2  the 


6^  The    Analyst. 

the  Velocities  generating  in  the  two  firft 
Moments,  from  the  excefs  of  the  Velocity 
in  the  third  above  that  in  the  fecond  Mo- 
ment, we  obtain  the  third  Fluxion.  And 
after  the  fame  Analogy  we  may  proceed  to 
fourth,  fifth,  fixth  Fluxions,  &c:  And  if 
we  call  the  Velocities  of  the  firft,  fe- 
cond, third,  fourth  Moments  a,  b^  c^  d^ 
the  Series  of  Fluxions  will  be  as  above, 
a.  b — a.  c — 2^-4-^.  d — 3^+  3^5  —  a. 

ad  infnitumy  /.  e,  x,  x,  x.  x,  ad  infi- 
nitum, 

XLIV.  Thus  Fluxions  may  be  confider- 
ed  in  fundry  Lights  and  Shapes,  which 
feem  all  equally  difficult  to  conceive.  And 
indeed,  as  it  is  impoffible  to  conceive  Ve- 
locity without  time  or  fpace,  without 
either  finite  length  or  finite  Duration  |, 
it  muft  feem  above  the  powers  of  Men 
to  comprehend  even  the  firft  Fluxions. 
And  if  the  firft  are  incomprehenfible, 
what  ftiall  we  fay  of  the  fecond  and  third 
Fluxions,  G?^?  He  who  can  conceive  the 
beginning  of  a  beginning,  or  the  end  of 
an  end,  fomewhat  before  the  firft  or  after 

I  Sea.  31.  *     - 

ihe 


T  H   E     A   N  A  L  Y  S  t,  ^9 

the  laft,  may  be  perhaps  fliarpfighted 
enough  to  conceive  thefe  things.  But  moft 
Men  will,  I  believe>  find  it  impoffible  to 
underftand  them  in  any  fenfe  whatever. 

XLV.  One  would  think  that  Men  could 
notfpeak  too  exactly  onfo  nice  aSubjeA. 
And  yet,  as  was  before  hinted,  we  may 
often  obferve  that  the  Exponents  of  Fluxions 
or  Notes  reprefenting  Fluxions  arc  con- 
founded with  the  Fluxions  themfelves.  Is 
not  this  the  Cafe,  when  juft  after  the 
Fluxions  of  flowing  Quantities  were  faid 
to  be  the  Celerities  of  their  increafingi 
and  the  fecond  Fluxions  to  be  the  muta- 
tions of  the   firft  Fluxions    or  Celerities^ 

we  are  told  that  z.  z.  z,  z,  z,  z.  *  re- 
prefents  a  Series  of  Quantities,  whereof 
each  fubfequent  Quantity  is  the  Fluxion 
of  the  preceding ;  and  each  foregoing  is  a 
fluent  Quantity  having  the  following  one 
for  it^  Fluxion  ? 

XLVL  Divers  Series  of  Quantities  and 
Expreflions,  Geometrical   and  Algebraical^ 

*  De  Quadratura  Curvarum. 

F  3  may 


70  TheAnalyst. 

may  be  eafily  conceived,  in  Lines,  in  Sur- 
faces, in  Species,  to  be  continued  without 
end  or  limit.  But  it  will  not  be  found  fo 
eafy  to  conceive  a  Series,  either  of  mere 
Velocities  or  of  mere  nafcent  Increments, 
diftinft  therefrom  and  correfponding  there- 
unto. Some  perhaps  may  be  led  to  think 
the  Author  intended  a  Series  of  Ordinates, 
wherein  each  Ordinate  was  the  Fluxion  of 
the  preceding  and  Fluent  of  the  following, 
/•  e.  that  the  Fluxion  of  one  Ordinate  was 
it  felf  the  Ordinate  of  another  Curve; 
and  the  Fluxion  of  this  laft  Ordinate  was 
the  Ordinate  of  yet  another  Curve  >  and 
fo  on  ad  infinitum.  But  who  can  conceive 
how  the  Fluxion  (whether  Velocity  or 
nafcent  Increment)  of  an  Ordinate  fhould 
be  it  felf  an  Ordinate?  Or  more  than 
that  each  preceding  Quantity  or  Fluent  is 
related  to  its  Subfequent  or  Fluxion,  as  the 
Area  of  a  curvilinear  Figure  to  its  Ordi- 
nate 5  agreeably  to  what  the  Author  re- 
marks, that  each  preceding  Quantity  in 
fuch  Series  is  as  the  Area  of  a  curvili- 
near Figure,  whereof  the  Abfcifs  is  z^ 
and  the  Ordinate  is  the  following  Quan- 
tity. 

XLVII.  Upon 


'The   AnaIysj. 

XLVIL  Upon  chc  whole  it  appears  that 
the  Celerities    are  difmiiled,    and  iaftead 
thereof  Areas  and  Ordinates  are  introduced. 
But  however  expedient  fuch  Analogies  pr 
foch  Expreffions  may  be  found  for  facili- 
tating the   modern    Quadratures,    yet  we 
fhall  not  find  any  light  given  us  thereby 
into  the  original  real  nature  of  Fluxions; 
or  that  we  are  enabled  to  frame  from  thence 
juft  Ideas  of  Fluxions  confidered  in  them- 
felves.    In  all   this  -the    general  ukimaie 
drift  of  the  Author  is  v^ry  clear,    but  hi^ 
Principles  are  obfcure.    But  perhaps  thoft 
Theories  of  the  great  Author  are    not  mi- 
nutely confidered  or  canvajQTed  by  his  Dif- 
dples  J    who  ieem  eager,    as   was  before 
hinted,  rather  to  operate  than  to  know, 
rather  to  apply  his  Rules  and  his  Forms^ 
than  to  underftand  his  Principles  and  en- 
ter into  his  Notions.  It  is  neverthelefs  cer- 
tain, that  in  order  to  follow  him  in  his 
Quadratures,  they  muft  find  Fl^uents  from 
Fluxioms ;  and  in  order  to  this,  they  muft 
know  to  find  Fluxions  from  Fluents ;  and 
in  order  to  find  Fluxions,  they  muft   firft 
know  vdiat  Fluxions  are.    Otherwife  they 
proceed    without  Clearnefs    and  without 
F  4  Seienee. 


y%  TheAnalyst. 

Science.  Thus  the  direct  Method  precedes 
the'  inverfe,  and  the  knowledge  of  the 
Principles  is  fuppofed  in  both.  But  as  for 
operating  according  to  Rules,  and  by  the 
help  of  general  Forms,  whereof  the  ori- 
ginal Principles  and  Reafons  are  not  on- 
derftood,  this  is  to  be  efteemed  merely 
technical.  Be  the  Principles  therefore  ever 
fo  abflrufe  and  metaphyfical,  they  muft 
be  ftudicd  by  whoever  would  comprehend 
the  Doctrine  of  Fluxions.  Nor  can  any 
Geometrician  have  a  right  to  apply  the 
Rules  of  the  great  Author,  without  firfl 
*  confidering  his  metaphyfical  Notions 
whence  they  were  derived.  Thefe  how 
neceffary  foever  in  order  to  Science, which 
can  never  be  attained  without  a  precife, 
clear,  and  accurate  Conception  of  the 
Principles,  are  neverthelefs  by  feveral 
carelefly  paffedover;  while  the  Expref- 
fions  alone  are  dwelt  on  and  coniidered 
and  treated  with  great  Skill  and  Manage- 
ment, thence  to  obtain  other  Expreffions 
by  Methods,  fufpicious  and  indirect  (to 
fay  the  lead)  if  confidered  in  themfelves, 
however   recommended   by  Induction  and 

Authorityj 


The    Analyst* 

Authority;  two  Motives  which  are  ac- 
knowledged fufficient  to  beget  a  rational 
Faith  and  moral  Perfuafion,  but  nothing 
higher. 

XL VIII.  You  may  poffibly  hope  to  e- 
vade  the  Force  of  all  that  hath  been  faid, 
and  to  fcreen  falfe  Principles  and  incon- 
fiftent  Reafonings,  by  a  general  Pretence 
that  thefe  Objedions  and  Remarks  are 
Metaphyfical.  But  this  is  a  vain  Pretence. 
For  the  plain  Senfe  and  Truth  of  what  is 
advanced  in  the  foregoing  Remarks,  I  ap- 
peal to  the  Underiftanding  of  every  un- 
prejudiced intelligent  Reader.  To  the 
fame  I  appeal,  whether  the  Points  re- 
marked upon  are  not  moft  incomprehen- 
fiblc  Metaphyfics.  And  Metaphyfics  not  of 
mine,  but  your  own.  I  would  not  be  un- 
derftood  to  infer,  that  your  Notions  are 
falfe  or  vain  becaufe  they  are  Metaphyfi- 
cal. Nothing  is  either  true  or  falfe  for 
that  Reafon.  Whether  a  Point  be  called 
Metaphyfical  or  no  avails  little.  The 
Queftion  is  whether  it  be  clear  or  obfcure, 
right  or  wrong,  well  or  ill-deduced  ? 

XLIX.  Al- 


7J 


^^  T  H  I     A  N  A  L  Y  S  t. 

XLIX.  Although  momentaneous  Incre- 
ments, nafccnt  and  evancfcent  Quantities, 
Fluxions  and  Infimtefimals  of  all  Dcgwes, 
are  in    truth  fuch  fhadowy  Entities,    fo 
difficult  to  imagine  or  conceive  diftin^tly, 
that  (to  fay  the  leaft)  they  cannot  be  ad- 
mitted as  Principles  or  Ol^ds  of  clear  and 
accurate  Science :    and  although  this  ob- 
fcurity  and   incomprehenfibility  of  your 
Metaphyfics  had  been  alone  fufEcient,  to 
allay  your  Prctenfions  to  Evidence  j  yet  it 
hath>  if  I  miftake  not,  been  further  fliewn, 
that  your  Inferences  are  no  more  juft  than 
your  Conceptions  are  clear,  and  that  your 
Logics  are  as  exceptionable  as  your  Meta- 
phyiics.     It  fhould    feem  therefore  upon 
the  whole,  that  your  Conclufions  are  not 
attained  by  juft  Reafoning  from  clear  Prin- 
ciples;    confequently    that   the   Employ- 
ment of  modern  Analyfts,  however  ufeful 
in  mathematical  Calculations,    and  Con- 
ftrudtions,  doth  not  habituate  and  qualify 
the  Mind  to  apprehend  clearly  and  infer 
juftly  ',  and  confequently,  that  you  have  no 
right  in  Virtue  of  fuch  Habits,  to  did:ate 
out  of  your  proper  Sphere,  beyond  which 

your 


Iv         T  H  E    A  K  A  L  ir  s  t.  71 

I     your   Judgment  is  to  pafs  for  no  mxjrc 


than  that  of  other  Men. 


li 


L.  Of  a  long  time  I  have  fufpcdkd,  that 
thefe  modern  Analytics  were  not  fcientifi- 
cal,  and  gavefomc  Hints  thereof  to  the  Pub- 
lic  about  twenty   five  Years  ago.     Since 
which  time,  I  have  been  diverted  by  other 
Occupations,  and  imagined  I  might  em- 
ploy my  felf  better  than  in  deducing  and 
laying  together  my  Thoughts  on  fo  nice 
a  Subje<a.     And  though  of  late  I  have  been 
called  upon  to  make  good  my  Suggefti- 
ons;   yet  as   the  Perfon,    who  made  this 
Call,  doth  not  appear  to  think  maturely 
enough  to  underftand,  either  thofe  Meta- 
phyfics  which   he   would  refute,  or  Ma- 
thematics  which  he  would  patronize    I 
fhould  have  fpared  my  felf  the  trouble  of 
writing  for  his  Convidion.     Nor  /hould  I 
now  have  troubled  you  or  my  felf  with 
this  Addrcfs,  after  fo  long  an  Intermiflion 
of  thefe  Studies ;  were  it  not  to  prevent, 
fo  far  as  I  am  able,  your  impofing  on  your 
felf  and  others  in  Matters  of  much  higher 
Moment  and  Concern.     And  to  the  end 
that  you  may  more    clearly   comprehend 

the 


jr^  The    Ana  l  y  s  r: 

the  Force  and  Defign  of  the  foregoing 
Remarks,  and  purfuc  them  ftill  further 
in  your  own  Meditations,  I  fhall  fubjoin 
the  following  Queries. 

^ery  I.  Whether  the  Objedl  of  Geome- 
try be  not  the  Proportions  of  affignable 
Extenfions?  And  whether,  there  be  any 
need  of  confidering  Quantities  either  in- 
finitely great  or  infinitely  fmall  ? 

^.  2.  Whether  the  end  of  Geometry 
be  not  to  mcafure  affignable  finite  Ex- 
tenfion  ?  And  whether  this  practical  View 
did  not  firft  put  Men  on  the  ftudy  of 
Geometry  ? 

^.  3.  Whether  the  miftaking  the  Ob- 
jedt  and  End  of  Geometry  hath  not  crea- 
ted needlefs  Difficulties,  and  wrong  Puf- 
fuits  in  that  Science  ? 

^.  4.  Whether  Men  may  properly  be 
faid  to  proceed  in  a  fcientific  Method, 
without  clearly  conceiving  the  Object  they 
are  converfant  about,  the  End  propofed, 
and  the  Method  by  which  it  is  purfued  ? 

^.  5.  Wiie- 


ThV  Analyst.  7;^ 

^.  5.  Whether  it  doth  not  fuffice,  that 
every  affignable  number  of  Parts  may  be 
contained  in  fome  affignable  Magnitude  ? 
And  whether  it  be  not  unneceflary,  as  well 
as  abfurd,  to  fuppofe  that  finite  Extenfioii 
is  infinitely  divifible  ? 

^.  6.  V/hether  the  Diagran^s  in  a  Geo- 
metrical Demonftration  are  not  to  be  confi- 
dered,  as  Signs  of  all  poffible  finite  Fi- 
gures, of  all  fenfible  and  imaginable  Ex- 
tenfions  or  Magnitudes  of  the  fame  kind  ? 

^.  7.  Whether  it  be  poffible  -to  free 
Geometry  from  infuperable  Difficylties  and 
Abfurdities,  fp  long  as  either,  the  abftracl 
general  Idea  of  Extenfion,  or  abfolute  ex- 
ternal Extenfion  be  fuppofed  its  true  Ob-r 
jed? 

^.  8.  Whether  the  Notions  of  abfolute 
Time,  abfolute  Place,  and  abfolute  Mo- 
tion be  not  moft  abfl.rad:edly  Metaphyfi- 
cal  ?  Whether  it  be  poffible  for  us  to  mea- 
fure,  compute,  or  know  them  ? 

^.  9.  Whether  Mathematicians  do  not 
engage  themfelves   in  Difpute3  and  Para- 
doxes, 


^8  T  HE     A  N  AL  Y  S  T. 

doxes,  concerning  what  they  neither  do 
nor  can  conceive  ?  And  whether  the  Doc- 
trine of  Forces  be  not  a  fufficient  Proof  of 
this?  * 

^.  10.  Whether  in  Geometry  ir  may 
not  fuffice  to  confider  affignable  finite  Mag- 
nitude, without  concerning  our  felves  with 
Infinity?  And  whether  it  would  not  be 
Tighter  to  meafure  large  Polygons  having 
finite  Sides,  inftead  of  Curves,  than  to 
fuppofc  Curves  are  Polygons  of  infinitefi- 
mal  Sides,  a  Suppofition  neither  true  nor 
conceivable  ? 

Slu,  II,  Whether  many  Points,  which 
are  not  readily  affented  to,  are  not  never- 
thelefs  true?  And  whether  thofe  in  the 
two  following  Queries  may  not  be  of  that 
Number  ? 

%.  13.  Whether  it  be  poffible,  that 
we  fhould  have  l^ad  an  Idea  or  Notion  of 
Extenfion  prior  to  Motion?  Or  whether 
if  a  Man  had  never  perceived  Motion,  he 
would  ever  have  known  or  conceived  one 
thing  to  be  diftant  from  another  ? 

*  See  a  Latin  Trc^tife  De  Motu,  publifhed  at  London, 
in  the  Year  1721. 

^.  13.  Whe- 


H  TheAnalysT.  ^9 

Qui.  13.  Whether  Geometrical  Quantity 
hath  coexiftcnt  Parts  ?  And  whether  all 
Quantity  be  not  in  a  flux  as  well  as  Time 
^nd  Motion  ? 

^.  14.  Whether  Extenfion  can  be  fup- 
pofed  an  Attribute  of  a  Being  inrmiutable 
and  eternal  ? 

^.  15.  Whether  to  decline  examining 
the  Principles,  and  unravelling  the  Me- 
thods ufed  in  Mathematics,  would  not 
fhew  a  bigotry  in  Mathematicians  ? 

%.  16.  Whether  certain  Maxims  do 
not  pafs  current  among  Analyfls,  which 
are  fhocking  to  good  Senfe  ?  And  whether 
the  common  Affumption  that  a  finite 
Quantity  divided  by  nothing  is  infinite  be 
not  of  this  Number  ? 

^.  17.  Whethpr  the  confidering  Geo- 
n^trical  Diagrams  abfolutely  or  in  them- 
fejves,  rather  than  as  Reprefentatives  of 
mi  aflignable  Magnitudes  or  Figures  of 
the  fame  kind,  be  not  a  principal  Caufe 
of  ;hc  fuppofing  finite  Extenfion  infinite- 


3o    .  TheAnalyst: 

ly  divifible ;  and  of  all  the  Difficulties  and 
Abfurdities  confequent  thereupon  ? 

^i.  1 8.  Whether  from  Geometrical 
Propofitions  being  general,  and  the  Lines 
in  Diagrams  being  therefore  general  Sub- 
flitutes  or  Reprefentatives,  it  doth  not  fol^ 
low  that  we  may  not  limit  or  confider  the 
number  of  Parts,  into  which  fuch  parti- 
ticular  Lines  are  divifible? 

^.  19.  When  it  is  faid  or  implied, 
that  fuch  a  certain  Line  delineated  on 
Paper  contains  more  than  any  affignable 
number  of  Parts,  whether  any  more  in 
truth  ought  to  be  underftood,  than  that 
it  is  a  Sign  indifferently  reprefenting  all- 
finite  Lines,  be  they  ever  fo  great.  In' 
which  relative  Capacity  it  contains,  /.  ej 
ftands  for  more  than  any  effignable  num- 
ber of  Parts  ?  And  whether  it  be  not  alto-' 
gether  abfurd  to  fuppofe  a  finite  Line, 
confidered  in  it  felf  or  in  its  own  pofitive 
Nature,  flibuld  contain  an  infinite  num-r- 
ber  of  Parts  ? 

^.  20.  Whether  all  Arguments  for. 
the  infinite  Divifibility  of  finite  Extenfion 

do 


The    Analyst.  S i 

do  not  fuppofe  and  imply,  either  general 
abftrad:  Ideas  or  abfolute  external  Exten- 
fion  to  be  the  Objedt  of  Geometry  ?  And, 
therefore,  whether,  along  with  thofe  Sup- 
pofitions,  fuch  Arguments  alfo  do  not 
ceafe  and  vanifh  ? 

^.  21.  Whether  the  fuppofed  infinite 
Divifibility  of  finite  Extenfion  hath  not 
been  a  Snare  to  Mathematicians,  and  a 
TKorn  in  their  Sides  ?  And  whether  a 
Quantity  infinitely  diminiflied  and  a  Quan* 
tity  infinitely  fmall  are  not  the  fame 
thing  ? 

^.  22.  Whether  it  be  neceflary  to 
confider  Velocities  of  nafcent  or  eva- 
nefcent  Quantities,  or  Moments,  or  Infi- 
nitefimals?  And  whether  the  introducing 
of  Things  fo  inconceivable  be  not  a  re- 
proach to  Mathematics  ? 

^.  23.  Whether  Inconfiftencies  can 
be  Truths  ?  Whether  Points  repugnant  and 
abfurd  are  to  be  admitted  upon  any  Sub- 
je<5l,  or  in  any  Science?  And  whether. the 
ufe  of  Infinites  ought  to  be  allowed,  as  a 
G  fufficient; 


8i  The    Analyst. 

fufficicnt  Pretext  and  Apology,  for  the  ad- 
mitting of  fuch  Points  in  Geometry  ? 

^.  24.  Whether  a  Quantity  be  not 
properly  faid  to  be  known,  when  we 
know  its  Proportion  to  given  Quantities  ? 
And  whether  this  Proportion  can  be 
known,  but  by  Expreffions  or  Exponents, 
either  Geometrical,  Algebraical,  or  Arith- 
metical ?  And  whether  Expreffions  in 
Lines  or  Species  can  be  ufeful  but  fo  far 
forth  as  they  are  reducible  to  Numbers  ? 

25.  Whether  the  finding  out  proper 
Expreffions  or  Notations  of  Quantity  be 
not  the  moft  general  Character  and  Ten- 
dency of  the  Mathematics  ?  And  Arithme- 
tical Operation  that  which  limits  and 
defines  their  Ufe  ? 

^.  26.  Whether  Mathematicians  have 
fufficiently  confidered  the  Analogy  and  Ufe 
of  Signs?  And  how  far  the  fpecific  limit- 
ed Nature  of  things  correfponds  thereto? 

^.  27.  Whether  becaufe,  in  ftating  a 
general  Cafe  of  pure  Algebra,  we  are  at 

full 


I 


The    Analyst.  8j 

full  liberty  to  make  a  Charaifter  denote, 
either  a  pofitive  or  a  negative  Quantity, 
or  nothing  at  all,  we  may  therefore  in  a 
geometrical  Cafe,  limited  by  Hypothefes 
and  Reafonings  from  particular  Proper- 
ties and  Relations  of  Figures,  claim  the 
fame  Licence  ? 

^,  28.  Whether  the  Shifting  of  the 
Hypothefis,  or  (as  we  may  call  it)  the  fal^ 
lacia  Suppojitionis  be  not  a  Sophifm,  that 
far  and  wide  infedts  the  modern  Rea- 
fonings, both  in  the  mechanical  Philo- 
fophy  and  in  the  abftrufe  and  fine  Geo- 
metry ? 

^«.  29.  Whether  we  can  form  an  Idea 
or  Notion  of  Velocity  diftind:  from  and 
exclufive  of  its  Meafures,  as  we  can  of 
Heat  diftin(5t  from  and  exclufive  of  the 
Degrees  on  the  Thermometer,  by  which 
it  is  meafured  ?  And  whether  this  be  not 
fuppofed  in  the  Reafonings  of  modern 
Analyfts  ? 

^.  30.  Whether  Motion  can  be  con- 
eeived  in  a  Point  of  Space  ?  And  if  Mo- 

G  2  tion 


§4  The    Analyst. 

tion  cannot,  whether  Velocity  can  ?  And 
if  not,  whether  a  firft  or  laft  Velocity 
can  be  conceived  in  a  mere  Limit,  ei- 
ther initial  or  final,  of  the  defcribed 
Space  ? 

^.  31.  Where  there  are  no  Incre- 
ments, whether  there  can  be  any  Ratio 
of  Increments  ?  Whether  Nothings  can 
be  confidered  as  proportional  to  real  Quan- 
tities ?  Or  whether  to  talk  of  their  Pro- 
portions be  not  to  talk  Nonfenfe  ?  Alfo  in 
what  Senfe  we  are  to  underftand  the 
Proportion  of  a  Surface  to  a  Line,  of' 
an  Area  to  an  Ordinate  ?  And  whether 
Species  or  Numbers,  though  properly  ex- 
preffing  Quantities  which  are  not  homo- 
geneous, may  yet  be  faid  to  exprefs  their 
Proportion  to  each  other? 

^.  32.  Whether  if  all  aflignable  Cir- 
cles may  be  fquared,  the  Circle  is  not, 
to  all  intents  and  purpofes,  fquared  as 
well  as  the  Parabola?  Or  whether  a  pa- 
rabolical Area  can  in  fadl  be  meafured 
more  accurately  than  a  Circular  ? 

%  33.  Whe- 


r 


T  H   E     A  N  A  L  Y  S  T.  85 

^.  33.  Whether  it  would  not  be 
righter  to  approximate  fairly,  than  to 
endeavour  at  Accuracy  by  Sophifms  ? 

^^  34.  Whether  it  would  not  be  more 
decent  to  proceed  by  Trials  and  Induc- 
tions, than  to  pretend  to  demonflrate  by 
falfe  Principles  ? 

^.  35.  Whether  there  be  not  a  way 
of  arriving  at  Truth,  although  the  Prin- 
ciples are  not  fcientific,  nor  the  Reafon- 
ing  juft  ?  And  whether  fuch  a  way  ought 
to  be  called  a  Knack  or  a  Science  ? 

^.  36.  Whether  there  can  be  Science 
of  the  Conclufion,  where  there  is  not 
Science  of  the  Principles  ?  And  whether 
a  Man  can  have  Science  of  the  Princi- 
ples, without  underftanding  them  ?  And 
therefore  whether  the  Mathematicians 
of  the  prefent  Age  adl  like  Men  of 
Science,  in  taking  fo  much  more  pains 
to  apply  their  Principles,  than  to  under- 
ftand  them  ? 

G  3         ^«.  37,  Whe- 


9^  T  H  E     A  N  A  L  Y  S  T. 

^.  37.  Whether  the  greateft  Genius 
wreftling  with  falfe  Principles  may  not  be 
foiled?  And  whether  accurate  Quadratures 
can  be  obtained  without  new  Foftulata  or 
Affumptions  ?  And  if  not,  whether  thofe 
which  are  intelligible  and  confiftent  ought 
not  to  be  preferred  to  the  contrary  ?  See 
Sed.  XXVIII  and  XXIX. 

^.  38.  Whether  tedious  Calculations 
in  Algebra  and  Fluxions  be  the  liklieft 
Method  to  improve  the  Mind  ?  And  whe- 
ther Mens  being  accuftomed  to  reafon 
altogether  about  Mathematical  Signs  and 
Figures,  doth  not  make  them  at  a  lofs  how 
to  reafon  without  them? 

%/.  39.  Whether,  whatever  readinefs 
Analyfts  acquire  in  ftating  a  Problem,  or 
finding  apt  Expreffions  for  Mathematical 
Quantities,  the  fame  doth  neceflarily  in- 
fer a  proportionable  ability  in  conceiving 
and  expreffing  other  Matters  ? 

i^/.  40.  Whether  it  be  not  a  general 
Cafe  or  Rule,  that  one  and  the  fame  Co- 
efficient   dividing  equal  Produd:s  gives  e- 

qual 


b 


T  H  E     A  N  A  L  Y  S  T.  87 

qual    Quotients  ?    And  yet  whether  fuch 
Coefficient    can    be   interpreted    by  o  or; 
nothing  ?  Or  whether  any  one  will  fay,' 
that  if  the  Equation  2  x  0  =  5  x  c?,  be  di- 
vided by  (?,  the  Quotients  on  both  Sides 
are    equal?     Whether  therefore    a    Cafe 
may   not   be  general  with   refpedl  to  all 
Quantities,    and  yet  not  extend   to  No- 
things, or  include  the  Cafe  of  Nothing? 
And   whether    the  bringing  Nothing  un- 
der the  Notion  of  Quantity  may  not  have 
betrayed  Men  into  falfc  Reafoning  ? 


^.  41.  Whether  in  the  mofl  general 
Reafonings  about  Equalities  and  Propor- 
tions, Men  may  not  demonflrate  as  well 
as  in  Geometry?  Whether  in  fuch  De- 
monflrations,  they  arc  not  obliged  to  the 
fame  flrid;  Reafoning  as  in  Geometry  ? 
And  whether  fuch  their  Reafonings  are  not 
deduced  from  the  fame  Axioms  with  thofe 
in  Geometry  ?  Whether  therefore  Alge- 
bra be  not  as  truly  a  Science  as  Geo- 
metry ? 

^.  42.  Whether  Men  may  not  reafon 
in  Species  as  well  as  in  Words?  Whether  . 
G  4  the 


8S  T  HE     A  N  A  L  Y  S  T. 

the  fame  Rules  of  Lpglc  do  not  obtain  in 
both  Cafes  ?  And  whether  we  have  not  a 
right  to  expcd  and  demand  the  fanie  Evi- 
dence in  both  ? 

^L  43.  Whether  an  Algebraift,  Fluxio- 
nift,  Geometrician  or  Demonftrator  of  any 
YmA  can  expedl  indulgence  for  obfcure 
Principles  or  incorred  Reafonings?  And 
v^hether  an  Algebraical  Note  or  Species 
»  can  at  the  end  of  a  Procefs  be  interpreted 
in  a  Senfe,  which  could  not  have  been  fub- 
ftituted  for  it  at  the  beginning  ?  Or  whe- 
ther any  particular  Suppofition  can  come 
under  a  general  Cafe  which  doth  not  con- 
fift  with  the  reafoning  thereof  ? 

%f.  44.  Whether  the  Difference  be- 
tween a  mere  Computer  and  a  Man  of 
Science  be  nor,  that  the  one  computes  on 
Principles  clearly  conceived,  and  by  Rules 
evidently  demonftrated,  whereas  the  other 
doth  not  ? 

^.  45.    Whether,  although  Geometry 
be  a  Science,  and   Algebra  allowed  to  be  a 
Science,  and  the  Analytical  a  moil   excel- 
lent 


The    Analyst.  8^ 

licnt  Method,  in  the  Application  neverthe- 
Icfs  of  the  Analyfis  to  Geometry,  Men  may 
not  have  admitted  falfe  Principles  and 
wrong  Methods  of  Reafoning  ? 

^.  46.  Whether  although  Algebraical 
Reafonings  are  admitted  to  be  ever  fo  juft, 
when  confined  to  Signs  or  Species  as  gene- 
ral Reprefentatives  of  Quantity,  you  may 
not  neverthelefs  fall  into  Error,  if,  when 
you  limit  them  to  ftand  for  particular 
things,  you  do  not  limit  your  felf  to  rca- 
fon  confiftently  with  the  Nature  of  fuch 
particular  things  ?  And  whether  fuch  Er- 
ror ought  to  be  imputed  to  pure  Algebra  ? 

%.  47.  Whether  the  View  of  modern 
Mathematicians  doth  not  rather  feem  to  be 
the  coming  at  an  Expreflion  by  Artifice, 
than  the  coming  at  Science  by  Demonftra- 
tion  ? 

I.i  ^.  48.  Whether  there  may  not  be 
found  Metaphyfics  as  well  as  unfound? 
Sound  as  well  as  unfound  Logic?  And 
I  ivhether  the  modern  Analytics  may  not  be 
brought  under  one  of  tjiefe  Denominations, 
and  which? 

^.  49.  Whe- 


jS  T  H  E     A  N  A  L  Y  S  T. 

^.  49.  Whether  there  be  not  really  a 
Philofophm  prima,  a  certain  tranfcenden- 
tal  Science  fuperior  to  and  more  exteniive 
than  Mathematics,  which  it  might  behove 
our  modern  Analyfts  rather  to  learn  than 
defpife  ? 

^.  50.  Whether  ever  fince  the  recovery 
of  Mathertiatical  Learning,  there  have  not 
been  perpetual  Difputes  and  Controverfies 
among  the  Mathematicians  ?  And  whether 
this  doth  not  difparage  the  Evidence  of 
their  Methods  ? 

^.  51.  Whether  any  thing  but  Meta- 
phyfics  and  Logic  can  open  the  Eyes  of 
Mathematicians  and  extricate  them  out  of 
their  Difficulties  ? 

^.  ^2.  Whether  upon  the  received 
Principles  a  Quantity  can  by  any  Divifion 
or  Subdivifion,  though  carried  ever  fo  far, 
be  reduced  to  nothing  ? 

%/.  53.  Whether  if  the  end  of  Geo- 
metry be  Pradtice,  and  this  Practice  be 
Meafuring,  and  \y&  meafure  only  affigna- 

ble 


The    Analy  s  t. 

ble  Extenfions,  it  will  not  follow  that  un- 
limited Approximations  compleatly  an- 
fwcr  the  Intention  of  Geometry  ? 

^.  54.  Whether  the  fame  things  which 
are  now  done  by  Infinites  may  not  be  done 
by  finite  Quantities?  And  whether  this 
would  not  be  a  great  Relief  to  the  Imagi- 
nations and  Underilandings  of  Mathema- 
tical Men  ? 

^.  55,  Whether  thofe  Philomathema- 
tical  Phyficians,  Anatomifts,  and  Dealers 
in  the  Animal  Oeconomy,  who  admit  the 
Dodbrine  of  Fluxions  with  an  implicit 
Faith,  can  with  a  good  grace  infult  other 
Men  for  believing  what  they  do  not  com- 
prehend ? 

^.  56.  Wlicther  the  Corpufcularian, 
Experimental,  and  Mathematical  Philo- 
fophy  fo  much  cultivated  in  the  laft  Age, 
hath  not  too  much  cngroffed  Mens  At- 
tention; fome  part  whereof  it  might  have 
ufefuUy  employed  ? 

^.  ^j,  Whe- 


51 


!t  - 


SI  T  HE     A  N  A   L  Y  S  T. 

^.  57.  Whether  from  this,  and  other 
concurring  Caufes,  the  Minds  of  fpecula- 
tive  Men  have  not  been  born  downward, 
to  the  debafing  and  ftupifying  of  the 
higher  Faculties  ?  And  whether  we  may  not 
hence  account  for  that  prevailing  Narrow- 
nefs  and  Bigotry  among  many  who  pafs  for 
Men  of  Science,  their  Incapacity  for  things 
Moral,  Intelledtual,  or  Theological,  their 
Pronenefs  to  meafure  all  Truths  by  Senfe 
and  Experience  of  animal  Life  ? 

^.  58.  Whether  it  be  really  an  EfFe(ft 
of  Thinking,  that  the  fame  Men  admire 
the  great  Author  for  his  Fluxions,  and  de- 
ride him  for  his  Religion  ? 

^/.  59.  If  certain  Philofophical  Vir- 
tuofi  of  the  prefent  Age  have  no  Religion, 
whether  it  can  be  faid  to  be  for  want  of 
Faith  > 

^,  60.  Whether  it  be  not  ajufter  way 
of  reafoning,  to  recommend  Points  of 
Faith  from  their  Effeds,  than  to  demon- 
ftrate  Mathematical  Principles  by  their 
Conclufions  ? 

^.61.  Whe- 


IPI^^    The    Analyst.  5>5 

^^.  6 1.  Whether  it  be  not  lefs  exccp- 
I      tionable    to   admit    Points  above  Reafon 
than  contrary  to  Reafon  ? 

^u.  62.  Whether  Myfteries  may  not 
with  better  right  be  allowed  of  in  Divine 
Faith,  than  in  Humane  Science  ? 

^.  63.  Whether  fuch  Mathematicians 
as  cry  out  againft  Myfteries,  have  ever 
examined  their  own  Principles  ? 

^.  64.  Whether  Mathematicians,  who 
are  fo  delicate  in  religious  Points,  are  flrid:- 
ly  fcrupulous  in  their  own  Science  ?  Whe- 
ther they  do  not  fubmit  to  Authority,  take 
things  upon  Truft,  believe  Points  incon- 
ceivable ?  Whether  they  have  not  their 
Myfteries,  and  what  is  more,  their  Re- 
pugnancies and  Contradidions? 

^.  65.  Whether  it  might  not  become 
Men,  who  are  puzzled  and  perplexed  a- 
bout  their  own  Principles,  to  judge  wari- 
ly, candidly,  and  modeftly  concerning  o- 
ther  Matters? 

^r/.66.  Whe- 


J4  T  HE     A  N  AL  Y  S  T. 

^.  66.  Whether  the  modern  Analytics 
do  not  furnifli  a  ftrong  argumentum  ad  ho- 
minem^  againft  the  Philomathematical  In- 
fidels of  thefc  Times  ? 

^.  67.  Whether  it  follows  from  the 
abovementioned  Remarks,  that  accurate 
and  juft  Reafoning  is  the  peculiar  Cha- 
radler  of  the  prefent  Age?  And  whether 
the  modern  Growth  of  Infidelity  can  be 
afcribed  to  a  Diftindlion  fo  truly  valuable  > 


FINIS. 


fe 


S?,  36,  It