that everything has its own separate
property. For grant that those ancient Servilii who were twins were as
much alike as they are said to have been, do you think that that would
have made them the same? They were not distinguished from one another out
of doors, but they were at home. They were not distinguished from one
another by strangers, but they were by their own family. Do we not see
that this is frequently the case, that those people whom we should never
have expected to be able to know from one another, we do by practice
distinguish so easily that they do not appear to be even in the least
alike?

Here, however, you may struggle; I will not oppose you. Moreover, I will
grant that that very wise man who is the subject of all this discussion,
when things like one another come under his notice, in which he has not
remarked any special character, will withhold his assent, and will never
agree to any perception which is not of such a character as a false
perception can never assume. But with respect to all other things he has a
certain art by which he can distinguish what is true from what is false;
and with respect to those similitudes he must apply the test of
experience. As a mother distinguishes between twins by the constant
practice of her eyes, so you too will distinguish when you have become
accustomed to it. Do you not see that it has become a perfect proverb that
one egg is like another? and yet we are told that at Delos (when it was a
flourishing island) there were many people who used to keep large numbers
of hens for the sake of profit; and that they, when they had looked upon
an egg, could tell which hen had laid it. Nor does that fact make against
our argument; for it is sufficient for us to be able to distinguish
between the eggs. For it is impossible for one to assent to the
proposition that this thing is that thing more, than by admitting that
there is actually no difference at all between the two. For I have laid it
down as a rule, to consider all perceptions true which are of such a
character as those which are false cannot be. And from this I may not
depart one finger's breadth, as they say, lest I should throw everything
into confusion. For not only the knowledge of what is true and false, but
their whole nature too, will be destroyed if there is no difference
between one and the other. And that must be very absurd which you
sometimes are in the habit of saying, when perceptions are imprinted on