Aristotle

He who can be, and therefore is, another’s, and he who participates in reason enough to apprehend, but not to have, is a slave by nature.

For as the eyes of bats are to the blaze of day, so is the reason in our soul to the things which are by nature most evident of all.

The moral virtues, then, are produced in us neither by nature nor against nature. Nature, indeed, prepares in us the ground for their reception, but their complete formation is the product of habit.

Hence poetry is something more philosophic and of graver import than history, since its statements are rather of the nature of universals, whereas those of history are singulars.

Man is by nature a political animal.

Nature does nothing in vain.

All men by nature desire knowledge.

All human actions have one or more of these seven causes: chance, nature, compulsions, habit, reason, passion, desire.