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.

(2) What then is a "moral virtue," the result of such a process duly
directed? It is no mere mood of feeling, no mere liability to emotion,
no mere natural aptitude or endowment, it is a permanent _state_ of the
agent's self, or, as we might in modern phrase put it, of his will,
it consists in a steady self-imposed obedience to a rule of action