Plato says that the city arises from an individual’s inability to meet his own physical needs; Aristotle says that it arises because men are political by nature. At first glace, it seems like Aristotle’s account is facile, or even that it is no explanation at all: “men are naturally political because they are political by nature! What an insight!” But Aristotle’s explanation is the better one. In effect, he is insisting that political life is irreducible. It is not the result of a more fundamental drive or desire – political life itself is the fundamental desire, and it would remain so even if it was not as good at meeting physical needs. This is why his Politics doesn’t begin by considering the individual (and his needs) as the principle of a society, but takes communal life as irreducible.
On Plato’s account the state meets the minimal requirements of its existence when it meets the basic physical needs of the individual. On Aristotle’s account the state meets such conditions when it provides a way for man to live a political life. Now it’s certainly ridiculous to critique Plato or Aristotle after limiting their political theories to their first principle, but such a limitation helpfully shows different fundamental views of what political order should be. If political order is really based on meeting basic physical needs, it is not immediately clear that there is a role for everyone as a citizen. Strong-man or paternalistic governments – in which there are no citizens but only dependents or consumers – could have a place among just regimes. But if political life is a basic and irreducible need, then just regimes must at least strive to make the regime a place in which the citizens can exercise a political life. Again, where political order reduces to physical need, the Leviathan-state is possible and perhaps even desirable; but where an individual’s political life is an irreducible reality, the Leviathan-state is in flagrant contradiction with the first principle of politics, since no one can lead a political life in the Leviathan state. The Leviathan might meet all the individual’s physical needs, but it does not allow his political actions to make anything beyond a negligible difference.