himself. But the second kind of likeness causes love of
concupiscence, or friendship founded on usefulness or pleasure:
because whatever is in potentiality, as such, has the desire for its
act; and it takes pleasure in its realization, if it be a sentient
and cognitive being.

Now it has been stated above (Q. 26, A. 4), that in the love of
concupiscence, the lover, properly speaking, loves himself, in
willing the good that he desires. But a man loves himself more than
another: because he is one with himself substantially, whereas with
another he is one only in the likeness of some form. Consequently,
if this other's likeness to him arising from the participation of a
form, hinders him from gaining the good that he loves, he becomes
hateful to him, not for being like him, but for hindering him from
gaining his own good. This is why "potters quarrel among themselves,"
because they hinder one another's gain: and why "there are
contentions among the proud," because they hinder one another in
attaining the position they covet.

Hence the Reply to the First Objection is evident.

Reply Obj. 2: Even when a man loves in another what he loves not in
himself, there is a certain likeness of proportion: because as the
latter is to that which is loved in him, so is the former to that
which he loves in himself: for instance, if a good singer love a good
writer, we can see a likeness of proportion, inasmuch as each one has
that which is becoming to him in respect of his art.

Reply Obj. 3: He that loves what he needs, bears a likeness to what
he loves, as potentiality bears a likeness to its act, as stated
above.

Reply Obj. 4: According to the same likeness of potentiality to its
act, the illiberal man loves the man who is liberal, in so far as he
expects from him something which he desires. The same applies to the
man who is constant in his friendship as compared to one who is
inconstant. For in either case friendship seems to be based on
usefulness. We might also say that although not all men have these
virtues in the complete habit, yet they have them according to
certain seminal principles in the reason, in force of which
principles the man who is not virtuous loves the virtuous man, as
being in conformity with his own natural reason.
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FOURTH ARTICLE [I-II, Q. 27, Art. 4]

Whether Any Other Passion of the Soul Is a Cause of Love?

Objection 1: It would seem that some other passion can be the ca