The Nicomachean ethics of Aristotle

Hence the several acts which determine goodness or badness of character must be done in a certain way, and thus the formation of good character requires discipline and direction from without. Not that the agent himself contributes nothing to the formation of his character, but that at first he needs guidance. The point is not so much that the process cannot be safely left to Nature, but that it cannot be entrusted to merely intellectual instruction. The process is one of assimilation, largely by imitation and under direction and control. The result is a growing understanding of what is done, a choice of it for its own sake, a fixity and steadiness of purpose. Right acts and feelings become, through habit, easier and more pleasant, and the doing of them a “second nature.” The agent acquires the power of doing them freely, willingly, more and more “of himself.” But what are “right” acts? In the first place, they are those that conform to a rule—to the right rule, and ultimately to reason. The Greeks never waver from the conviction that in the end moral conduct is essentially reasonable conduct. But there is a more significant way of describing their “rightness,” and here for the first time Aristotle introduces his famous “Doctrine of the Mean.” Reasoning from the analogy of “right” physical acts, he pronounces that rightness always means adaptation or adjustment to the special requirements of a situation. To this adjustment he gives a quantitative interpretation. To do (or to feel) what is right in a given situation is to do or to feel just the amount required—neither more nor less: to do wrong is to do or to feel too much or too little—to fall short of or over-shoot, “a mean” determined by the situation. The repetition of acts which lie in the mean is the cause of the formation of each and every “goodness of character,” and for this “rules” can be given.…