pinion is more common and more probable. For we must take note
that since every delectation results from some action, as stated in
_Ethic._ x, 4, and again, that since every delectation may be
compared to two things, viz. to the operation from which it results,
and to the object in which a person takes delight. Now it happens
that an action, just as a thing, is an object of delectation, because
the action itself can be considered as a good and an end, in which
the person who delights in it, rests. Sometimes the action itself,
which results in delectation, is the object of delectation, in so far
as the appetitive power, to which it belongs to take delight in
anything, is brought to bear on the action itself as a good: for
instance, when a man thinks and delights in his thought, in so far as
his thought pleases him; while at other times the delight consequent
to an action, e.g. a thought, has for its object another action, as
being the object of his thought; and then his thought proceeds from
the inclination of the appetite, not indeed to the thought, but to
the action thought of. Accordingly a man who is thinking of
fornication, may delight in either of two things: first, in the
thought itself, secondly, in the fornication thought of. Now the
delectation in the thought itself results from the inclination of the
appetite to the thought; and the thought itself is not in itself a
mortal sin; sometimes indeed it is only a venial sin, as when a man
thinks of such a thing for no purpose; and sometimes it is no sin at
all, as when a man has a purpose in thinking of it; for instance, he
may wish to preach or dispute about it. Consequently such affection
or delectation in respect of the thought of fornication is not a
mortal sin in virtue of its genus, but is sometimes a venial sin and
sometimes no sin at all: wherefore neither is it a mortal sin to
consent to such a thought. In this sense the first opinion is true.

But that a man in thinking of fornication takes pleasure in the act
thought of, is due to his desire being inclined to this act.
Wherefore the fact that a man consents to such a delectation, amounts
to nothing less than a consent to the inclination of his appetite to
fornication: for no man takes pleasure except in that which is in
conformity with his appetite. Now it is a mortal sin, if a man
deliberately chooses that his appetite be conformed to what is in
itself a mortal sin. Wherefore such a consent to delectatio