The Development of Political Institutions

"The mere gathering of individuals into a group does not constitute them a society. A society, in the sociological sense, is formed only when, besides juxtaposition, there is cooperation. So long as members of the group do not combine their energies to achieve some common end or ends, there is little to keep them together. They are prevented from separating only when the wants of each are better satisfied by uniting his efforts with those of others than they would be if he acted alone.
Cooperation, then, is at once that which cannot exist without a society, and that for which a society exists. It may be a joining of many strengths to effect something which the strength of no single man can effect; or it may be an apportioning of different activities to different persons, who severally participate in the benefits of one another's activities. The motive for acting together, originally the dominant one, may be defense against enemies; or it may be the easier obtainment of food, by the chase or otherwise; or it may be, and commonly is, both of these.
In any case, however, the units pass from the state of perfect independence to the state of mutual dependence; and as fast as they do this they become united into a society rightly so called..." -Political Organization in General -Political Integration -Political Differentiation -Political Forms and Forces -Political Heads - Chiefs, Kings, etc... -Compound Political Heads -Consultative Bodies -Representative Bodies -The Militant Type of Society