Federation of Free States

States, like individuals before the social contract, exist in a state of nature with respect to one another. Without a common authority to enforce agreements, each state must rely on its own power, and the result is a permanent condition of mutual threat. Reason demands that states, like individuals, exit this state of nature and establish a legal order — but how?

Kant rejects the idea of a single world state as both impractical and potentially tyrannical. A world government powerful enough to maintain peace among all nations would be a despotism that destroys the political diversity and republican self-governance that are themselves conditions of freedom. Instead, he advocates a 'pacific federation' — a league whose members renounce war, respect each other's sovereignty, and resolve disputes through negotiation.

Kant does not expect the federation to be established at once. He envisions a gradual process in which republican states, finding mutual advantage in peace, enter the federation one by one until it grows to encompass all nations. History, on this view, has a tendency — not a guarantee — toward the realisation of the legal conditions that reason requires. Commerce, communication, and the costs of war all work, over time, in favor of the federation.

The Second Definitive Article and the accompanying discussion of the law of nations appear in Section Two of Perpetual Peace.