Ethical egoism is consistent with Kant's theory of duty.

Ethical egoism is a self-interested theory that holds that individuals ought to act in their own best interests, regardless of the potential harm caused to others. In contrast, Kant's theory of duty is based on the idea of treating others as ends-in-themselves, rather than solely as means to an end. Therefore, ethical egoism and Kant's theory of duty are fundamentally incompatible.