xiv AFRICAN POLITICAL SYSTEMS
difficulty occurs also with the Tallensi and Nuer described in this volume and with many other societies in various parts of the world. It would doubtless be possible to find a definition of the word 'state* such that we could say that certain African societies, such as Ankole or the Bemba, are states, while others are stateless societies. This does not help us, however, to solve our problems. Every human society has some sort of territorial structure. We can find clearly-defined local communities the smallest of which are linked together in a larger s'ociety, of which they are segments. This territorial structure provides the framework, not only for the political organization, whatever it may be, but for other forms of social organization also, such as the economic, for example. The system of local aggregation and segregation, as such, has nothing specifically political about it; it is the basis of all social life. To try to distinguish, as Maine and Morgan did, between societies based on kinship (or, more strictly, on lineage) and societies based on occupation of a common territory or locality, and to regard the former as more 'primitive' than the latter, leads only to confusion.
In studying political organization, we have to deal with the maintenance or establishment of social order, within a territorial framework, by the organized exercise of coercive authority through the use, or the possibility of use, of physical force. In well-organized states, the police and the army are the instruments by which coercion is exercised. Within the state, the social order, whatever it may be, is maintained by the punishment of those who offend against the laws and by the armed suppression of revolt. Externally the state stands ready to use armed force against other states, either to maintain the existing order or to create a new one.
In dealing with political systems, therefore, we are dealing with law, on the one hand, and with war, on the other. But there are certain institutions, such as regulated vengeance, which come between the two. Let us first consider law, and within the field of law the machinery of repressive justice. Within a locally-defined community, an individual may commit some act or adopt some mode of behaviour which constitutes some sort of attack upon or offence against the community itself as a whole, and thereupon the offending person may be put to death or excluded from the community or in some way made to suffer. In simple