The Nicomachean ethics of Aristotle · Aristotle
Chapter IX.
Then, again, he who makes a small deflection from what is right, be it on the side of too much or too little, is not blamed, only he who makes a considerable one; for he cannot escape observation. But to what point or degree a man must err in order to incur blame, it is not easy to determine exactly in words: nor in fact any of those points which are matter of perception by the Moral Sense: such questions are matters of detail, and the decision of them rests with the Moral Sense.[24] At all events thus much is plain, that the mean state is in all things praiseworthy, and that practically we must deflect sometimes towards excess sometimes towards defect, because this will be the easiest method of hitting on the mean, that is, on what is right.
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