we must therefore set aside the vital activity of
nutrition and growth. Next in the scale will come some form of sentient life; but this too
appears to be shared by horses, oxen, and animals generally.
There remains therefore what may be called the practical1
life of the rational part of man. （This part has two divisions,2
rational as obedient to principle, the others possessing principle and exercising
intelligence）. Rational life again has two meanings; let us assume that we are
here concerned with the active exercise3
of the rational faculty, since
this seems to be the more proper sense of the term.
then the function of man is the active exercise of the soul's faculties4
in conformity with rational principle, or at all
events not in dissociation from rational principle, and if we acknowledge the function of
an individual and of a good individual of the same class （for instance, a harper
and a good harper, and so generally with all classes） to be generically the same,
the qualification of the latter's superiority in excellence being added to the function in
his case （I mean that if the function of a harper is to play the harp, that of a
good harper is to play the harp well）: if this is so, and if we declare that the
function of man is a certain form of life, and define that form of life as the exercise of
the soul's faculties and activities in association with rational principle,
and say that the function of a good man is to perform these
activities well and rightly, and if a function is well performed when it is performed in
accordance with its own proper excellence—from these premises it follows that
the Good of man is the active exercise of his soul's faculties in conformity with
excellence or virtue, or if there be several human excellences or virtues, in conformity
with the best and most perfect among them.
be happy takes a complete lifetime; for one swallow does not make spring, nor does one
fine day; and similarly one day or a brief period of happiness does not make a man supremely blessed5
Let this account then serve to describe the Good in outline—for no doubt the
proper procedure is to begin by making a rough sketch, and to fill it in afterwards. If a
work has been well laid down in outline, to carry it on and complete it in detail may be
supposed to be within the capacity of anybody; and in this working out of details Time
seems to be a good inventor or at all events coadjutor. This indeed is how advances in the
arts have actually come about, since anyone can fill in the gaps.
Also the warning given above6
must not be forgotten; we must not look for equal exactness in all
departments of study, but only such as belongs to the subject matter of each, and in such
a degree as is appropriate to the particular line of enquiry.
A carpenter and a geometrician both try to find a right angle,7
different ways; the former is content with that approximation to it which satisfies the
purpose of his work; the latter, being a student of truth, seeks to find its essence or
essential attributes. We should therefore proceed in the same manner in other subjects
also, and not allow side issues to outbalance the main task in hand.