iscourse.

II. But every discourse which is concerned in the investigation of any
matter, and which proceeds on any system and principle, ought first to
establish the rule (as is done in lawsuits, where one proceeds according
to set formulas), in order that it may be agreed between the parties to
the discussion, what the subject of the discussion really is. This rule
was approved by Epicurus, as it was laid down by Plato in his "Phaedrus,"
and he considered that it ought to be adopted in every controversy. But he
did not perceive what was the necessary consequence of it, for he asserts
that the subject ought not to be defined; but if this be not done, it is
sometimes impossible that the disputants should agree what the matter is
that is the subject of discussion, as in this very case which we are
discussing now, for we are inquiring into the End of Good. How can we know
what the character of this is, if, when we have used the expression the
End of Good, we do not compare with one another our ideas of what is meant
by the End, and of what the Good itself is?

And this laying open of things covered up, as it were, when it is once
explained what each thing is, is the definition of it; which you sometimes
used without being aware of it; for you defined this very thing, whether
it is to be called the End, or the extremity, or the limit, to be that to
which everything which was done rightly was referred, and which was itself
never referred to anything. So far was very well said; and, perhaps, if it
had been necessary, you would also have defined the Good itself, and told
us what that was; making it to be that which is desirable by nature, or
that which is profitable, or that which is useful, or that which is
pleasant: and now, since you have no general objections to giving
definitions, and do it when you please, if it is not too much trouble, I
should be glad if you would define what is pleasure, for that is what all
this discussion relates to.

As if, said he, there were any one who is ignorant what pleasure is, or
who is in need of any definition to enable him to understand it better.

I should say, I replied, that I myself am such a man, if I did not seem to
myself to have a thorough acquaintance with, and an accurate idea and
notion of, pleasure firmly implanted in my mind. But, at present, I say
that Epicurus himself does not know, and that he is greatly in error on
this subject; and that he who mentions the subject so