Three Kinds of Moral Rationalism

Kant argues that reason alone, not feelings or consequences, tells us what we ought to do. The book that introduced the categorical imperative and the boldest statement of moral rationalism.

Immanuel Kant

The Cambridge Platonist Ralph Cudworth argues that right and wrong are as unchangeable as the truths of geometry, not mere commands of God or the state. A founding text of moral rationalism, in the original 1731 edition.

Ralph Cudworth

Richard Price answers Hume and the moral sense theorists: our ideas of right and wrong come from the understanding, not from feeling. The classic case for rational intuitionism in ethics, in the 1769 second edition.

Richard Price