No More Learning

Immanuel Kant
243
Fundamental Principles of the Metaphysic of Morals
If then there is a supreme           principle or, in respect of the human will, a categorical imperative, it must be one which, being drawn from the conception of that which is necessarily an end for everyone because it is an end in itself, constitutes an objective prin- ciple of will, and can therefore serve as a universal practical law.