se a resemblance
between ourselves and the subject that suffers. Everywhere where this
resemblance makes itself known, pity is necessary; where this resemblance
is lacking, pity is impossible. The more visible and the greater is the
resemblance, the more vivid is our pity; and they mutually slacken in
dependence on each other. In order that we may feel the affections of
another after him, all the internal conditions demanded by this affection
must be found beforehand in us, in order that the external cause which,
by meeting with the internal conditions, has given birth to the
affection, may also produce on us a like effect. It is necessary that,
without doing violence to ourselves, we should be able to exchange
persons with another, and transport our Ego by an instantaneous
substitution in the state of the subject. Now, how is it possible to
feel in us the state of another, if we have not beforehand recognized
ourselves in this other.

This resemblance bears on the totality of the constitution of the mind,
in as far as that is necessary and universal. Now, this character of
necessity and of universality belongs especially to our moral nature.
The faculty of feeling can be determined differently by accidental
causes: our cognitive faculties themselves depend on variable conditions:
the moral faculty only has its principle in itself, and by that very fact
it can best give us a general measure and a certain criterion of this
resemblance. Thus an idea which we find in accord with our mode of
thinking and of feeling, which offers at once a certain relationship with
the train of our own ideas, which is easily grasped by our heart and our
mind, we call a true idea. If this relationship bears on what is
peculiar to our heart, on the private determinations that modify in us
the common fundamentals of humanity, and which may be withdrawn without
altering this general character, this idea is then simply true for us.
If it bears on the general and necessary form that we suppose in the
whole species, the truth of this idea ought to be held to be equal to
objective truth. For the Roman, the sentence of the first Brutus and the
suicide of Cato are of subjective truth. The ideas and the feelings that
have inspired the actions of these two men are not an immediate
consequence of human nature in general, but the mediate consequence of a
human nature determined by particular modifications. To share with them
these feelings we must have a