In order to live, man must act; in order to act, he must make choices; in order to make choices, he must define a code of values; in order to define a code of values, he must know what he is and where he is—i.e., he must know his own nature (including his means of knowledge) and the nature of the universe in which he acts—i.e., he needs metaphysics, epistemology, ethics, which means: philosophy. He cannot escape from this need; his only alternative is whether the philosophy guiding him is to be chosen by his mind or by chance.

- Ayn Rand. The Romantic Manifesto (1969).