234 HERBERT SPENCER

tively, with data drawn from the animal world and
from child-study, he attempted to trace the evolution
of mind from reflex action through instinct to reason,
memory, feeling, and will, by the interaction of the
nervous system with its gradually widening environ-
ment. Subjectively, in his analytic task, he en-
deavoured to show that all mental states are referable
to primitive elements of consciousness or units of
feeling, which he called nervous or psychical shocks.
Spencer's general position is thus summed up :—

"The Law of Evolution holds of the inner world as it
does of the outer world. On tracing up from its low and
vague beginnings the intelligence which becomes so marvel-
lous in the highest beings, we find that under whatever aspect
contemplated, it presents a progressive transformation of like
nature with the progressive transformation we trace in the
Universe as a whole, no less than in each of its parts. If
we study the development of the nervous system, we see it
advancing in integration, in complexity, in definiteness. If
we turn to its functions, we find these similarly show an ever-
increasing inter-dependence, an augmentation in number and
heterogeneity, and a greater precision. If we examine the
relations of these functions to the actions going on in the
world around, we see that the correspondence between them
progresses in range and amount, becomes continually more com-
plex and special, and advances through differentiations and in-
tegrations like those everywhere going on. And when we
observe the correlative states of consciousness, we discover that
these, too, beginning as simple, vague, and incoherent, become
increasingly numerous in their kinds, are united into aggregates
which are larger, more multitudinous, and more multiform,
and eventually assume those finished shapes we* see in
scientific generalisations, where definitely-quantitative ele-
ments are co-ordinated in definitely-quantitative relations"
[Principles of Psychologyt i. p. 627).

In Spencer's system mind is a secondary and deri-
vative expression of life; it emerges after corporeal so far