It is practice alone that brings the powers of the mind, as well as those of the body, to their perfection.
John LockeA criminal who, having renounced reason ... hath, by the unjust violence and slaughter he hath committed upon one, declared war against all mankind, and therefore may be destroyed as a lion or tiger, one of those wild savage beasts with whom men can have no society nor security.
John LockeIt is of great use to the sailor to know the length of his line, though he cannot with it fathom all the depths of the ocean.
John LockeIt is ambition enough to be employed as an under-labourer in clearing the ground a little, and removing some of the rubbish that lies in the way to knowledge.
John Locke