Groundwork of The Metaphysic of Morals - The Categorical Imperative

The Categorical Imperative

The categorical imperative is the centerpiece of the Groundwork. Although it may seem superficially similar to the Golden Rule, it is in no way equivalent. The Golden Rule demands that one's actions conform to one's own standard, whereas Kant's moral imperative places the standard for moral good in reason (directly contradicting Hume, who claimed reason could not be a ground for moral choices). He states that people should always be treated with respect to their personhood and dignity, and always as ends in themselves: they can be treated as a means and an end at the same time, but never only as a means.

Consider the example of the liar. The Golden Rule allows that lying to others may be acceptable under some conditions, but the categorical imperative determines lying immoral without exception. This could be considered to be a flaw in the Golden Rule, one that is corrected by insisting, as Kant does, that actions must be universal to be moral and by insisting that morality cannot be merely a matter of preference or taste.

Kant expanded and elucidated these ideas further in some of his later works, primarily the Critique of Practical Reason (1788, informally referred to as his Second Critique), Religion within the Limits of Reason Alone (1793) and the Metaphysics of Morals (1797).