Now our treatment of this science will be adequate, if it achieves that amount of
precision which belongs to its subject matter. The same exactness must not be expected in
all departments of philosophy alike, any more than in all the products of the arts and
The subjects studied by political science are
and Justice; but these conceptions involve much
difference of opinion and uncertainty, so that they are sometimes believed to be mere
conventions and to have no real existence in the nature of things.
And a similar uncertainty surrounds the conception of the Good, because
it frequently occurs that good things have harmful consequences: people have before now
been ruined by wealth, and in other cases courage has cost men their lives.
We must therefore be content if, in dealing with subjects
and starting from premises thus uncertain, we
succeed in presenting a broad outline of the truth: when our subjects and our premises are
merely generalities, it is enough if we arrive at generally valid conclusions. Accordingly
we may ask the student also to accept the various views we put forward in the same spirit;
for it is the mark of an educated mind to expect that amount of exactness in each kind
which the nature of the particular subject admits. It is equally unreasonable to accept
merely probable conclusions from a mathematician and to demand strict demonstration from
Again, each man judges correctly those matters with which he is acquainted; it is of
these that he is a competent critic. To criticize a particular subject, therefore, a man must have
been trained in that subject: to be a good critic generally, he must have had an all-round
education. Hence the young are not fit to be students of Political Science.2
have no experience of life and conduct, and it is these that supply the premises and
subject matter of this branch of philosophy.
they are led by their feelings; so that they will study the subject to no purpose or
advantage, since the end of this science is not knowledge but action.
And it makes no difference whether they are young in years or immature
in character: the defect is not a question of time, it is because their life and its
various aims are guided by feeling; for to such persons their knowledge is of no use, any
more than it is to persons of defective self-restraint.3
Moral Science may be of great value to those who guide their desires and actions by
Let so much suffice by way of introduction as to the student of the subject, the spirit
in which our conclusions are to be received, and the object that we set before