Kant's moral theory has been generally characterised in a variety of ways: as a formalist ethics, as an ethics of duty, as a deontological ethics, and so forth. But it is also an important feature of Kant's theory that it represents what we can call an ‘ethic of maxims.’ Otfried Höffe, one of the most thorough contemporary interpreters of Kant's thought, introduced this expression precisely to emphasise the central role played by the concept of a maxim in Kant's ethics. For, after all, the Categorical Imperative does not command: Act in this (or that way), nor does it instruct us: Act in accordance with this (or that) intention. What it actually prescribes is: ‘Act according to a maxim which can at the same time serve as a universal law.’ This is the formulation that Kant provides in the Metaphysics of Morals (Doctrine of Right: 6:225). But in all the other passages, in all of his other works, where he attempts to defi ne the Categorical Imperative, Kant always relates the latter explicitly to the role and signifi cance of maxims. It is precisely maxims, and maxims alone, as Höffe says, that form the authentic ‘object’ of the Categorical Imperative.

The following considerations do not attempt, as part of a general historical interpretation of Kant, to elucidate his ethical thought as a whole, nor to decide the best way of characterising his ethics as a whole, but simply to clarify the question of an ‘ethic of maxims’ itself.