Perpetual Peace: A Philosophical Sketch

These preliminary articles expose Kant’s observation of the moral failures of 18th-century politics and reveals Kant’s conviction that peace cannot emerge from self-interest alone. Instead, it must be grounded in moral law. Kant argues that The Moral Obligation of States compels them to adopt particular ethical principles that reflect the structure of an individual’s moral life. 

The articles reveal the relationship between moral obligation and political structure: States that violate moral principles sow the seeds of their own instability. Kant’s preliminary articles remove the incentives, structures, and behaviors that perpetuate violence. Each article counters a particular problem of 18th-century European diplomacy, secret treaties, territorial exchange and colonialism, standing armies, and debt-financed wars. Historically, these ideas were revolutionary. Written amid the turbulence of the late 18th century, in an age of class wars and colonial expansion, Kant’s principles challenged the normal logic of empire. His preference for moral restraint over political cunning provides a framework for modern international law and diplomacy.

The first article—prohibiting treaties that leave space for future wars—illustrates Kant’s central moral demand: Public honesty. A state that enters negotiations with hidden intent violates the categorical imperative because it relies on deception. For Kant, duplicity is a collapse of reason rather than an expression of cleverness. Furthermore, by redefining sovereignty as moral personality rather than property, Kant delivers a new way of thinking about the position of the government: States are not the possessions of rulers, but communities of citizens. Kant challenges the logic of the empire that dominated Europe during his life and anticipates a 20th-century principle of national self-determinism.

The prohibition of standing armies links morality with political economy. Permanent militarization converts human beings into instruments of power and turns peace into a temporary intermission between wars. Kant argues that limiting national debt and rejecting war finance will create lasting peace—an idea that anticipates modern concerns about nuclear weapons and the military-industrial complex.

The Preliminary Articles expose Kant’s awareness of structural violence. War is more than a breakdown of morality; it is intentionally sustained by economic, institutional, and strategic mechanisms that reward aggression. Kant’s response is neither pacific nor utopian. He argues that peace must be engineered through law.