Aristotle.

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

Men acquire a particular quality by constantly acting a particular way... you become just by performing just actions, temperate by performing temperate actions, brave by performing brave actions.

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.