Groundwork for the Metaphysics of Morals

Kant's Groundwork (1785) is the foundational text of deontological ethics, presenting the categorical imperative and the principle that persons must be treated as ends in themselves.

The Groundwork argues that moral worth depends solely on acting from duty, formulates the categorical imperative in three formulations (universal law, humanity as end, kingdom of ends), and grounds morality entirely in autonomous rational will rather than consequences or inclination.