A sound mind in a sound body is a short but full description of a happy state in this world.
John LockeIn transgressing the law of nature, the offender declares himself to live by another rule than that of reason and common equity.
John LockeAs it is in the body, so it is in the mind; practice makes it what it is, and most even of those excellencies, what are looked on as natural endowments, will be found, when examined into more narrowly, to be the product of exercise, and to be raised to that pitch, only by repeated actions.
John Locke