For the human race is not a race of isolated individuals, wandering and solitary; but it is so constituted that even in the affluence of all things [and without any need of reciprocal assistance, it spontaneously seeks society].
XXVI.

[It is necessary to presuppose] these original seeds, as it were, since we cannot discover any primary establishment of the other virtues, or even of a commonwealth itself.

These unions, then, formed by the principle which I have mentioned, established their headquarters originally in certain central positions, for the convenience of the whole population; and having fortified them by natural and artificial means, they called this collection of houses a city or town, distinguished by temples and public squares.

Every people, therefore, which consists of such an association of the entire multitude as I have described, every city which consists of an assemblage of the people, and every commonwealth which embraces every member of these associations, must be regulated by a certain authority, in order to be permanent.
This intelligent authority should always refer itself to that grand first principle which established the Commonwealth.

It must be deposited in the hands of one supreme person, or intrusted to the administration of certain delegated rulers, or undertaken by the whole multitude.