The Nicomachean Ethics — trans. F. H. Peters (1881)

Now science, we saw, implies demonstration ; but things whose principles or causes are variable do not admit of demonstration ; for everj'thing that depends upon these principles or causes is also variable ; and, on the other hand, things that are necessarOy determined do not admit of deliberation. It follows, therefore, that prudence cannot be either a science or an art : it cannot be a science, because the sphere of action is that which is altei-able ; it cannot be an art, because production is generically difierent from action.

It follows from all this that prudence is a formed faculty that apprehends truth by reasoning or calculation, and issues in action, in the domain of human good and ill ; for while production has another end than itself, this is not so with action, since good action or well doing is itself the end.

For this reason Pericles and men who resemble him are considered prudent, because they are able to see what is good for themselves and for men; and this we take to be the character of those who are able to manage a household or a state.

This, too, is the reason why we call temperance

188 NICOMACHEAN ETHICS OF AEISTOTLE. [Bk. YI.

a(o(j)po<Tvvr], signifying thereby that it is the virtue which preserves prudence. But what temperance 6 preserves is this particular kind of judgment. For it is not any kind of judgment that is destroyed or perverted by the presentation of pleasant or painful objects (not such a judgment, for instance, as that the angles of a triangle are equal to two right angles), but only judgments about matters of practice. For the principles of practice [or the causes which originate action] * are the ends for the sake of which acts are done ; but when a man is corrupted by pleasure or pain, he straightway loses sight of the principle, and no longer sees that this is the end for the sake of which, and as a means to which, each particular act should be chosen and done ; for vice is apt to obliterate the principle.

Our conclusion then is that prudence is a formed faculty which apprehends truth by reasoning or calculation, and issues in action, in the field of human good.

Moreover, art [or the artistic faculty] has its excel- 7 lence [or perfect development] in something other than itself, but this is not so with prudence. Again, in the domain of art voluntary error is not so bad as involuntary, but it is worse in the case of prudence, as it is in the case of all the virtues or excellences. It is plain, then, that prudence is a virtue or excellence, and not an art.

And the rational parts of the soul or the intellectual 8 faculties being two in number, prudence will be the

* The conception of tlie end is at once a cause or source of action and a principle of knowledge ; apxv covers both.

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virtue of the second, [the calculative part or] the faculty of opinion ; for opinion deals with that which is variable, and so does prudence.

But it is something more than " a formed faculty of apprehending truth by reasoning or calculation ; " as we see from the fact that such a faculty may be lost, but prudence, once acquired, can never be lost.*

6. Science is a mode of judging that deals vriih. (*) or Muiuniversal and necessary truths ; but truths that as the basis can be demonstrated depend upon principles, and stratitx tcienot.

(since science proceeds by demonstrative reasoning) every science has its principles. The principles, then, on which the truths of science depend cannot fall within the province of science, nor yet of art or prudence ; for a scientific truth is one that can be demonstrated, but art and prudence have to do with that which is variable.

Nor can they fall within the province of wisdom ; for it is characteristic of the wise man to have a demonstrative knowledcfe of certain thincjs.

But the habits of mind or formed faculties by which we apprehend truth without any mixture of en"or, whether in the domain of things invariable or in the domain of things vai'iable, are science, prudence, wisdom, and reason.t If then no one of the first three (prudence, science, wisdom) can be the faculty