s hinder him from
considering it. Now it hinders him in three ways. First, by way of
distraction, as explained above (A. 1). Secondly, by way of
opposition, because a passion often inclines to something contrary to
what man knows in general. Thirdly, by way of bodily transmutation,
the result of which is that the reason is somehow fettered so as not
to exercise its act freely; even as sleep or drunkenness, on account
of some change wrought on the body, fetters the use of reason. That
this takes place in the passions is evident from the fact that
sometimes, when the passions are very intense, man loses the use of
reason altogether: for many have gone out of their minds through
excess of love or anger. It is in this way that passion draws the
reason to judge in particular, against the knowledge which it has in
general.

Reply Obj. 1: Universal knowledge, which is most certain, does not
hold the foremost place in action, but rather particular knowledge,
since actions are about singulars: wherefore it is not astonishing
that, in matters of action, passion acts counter to universal
knowledge, if the consideration of particular knowledge be lacking.

Reply Obj. 2: The fact that something appears good in particular to
the reason, whereas it is not good, is due to a passion: and yet this
particular judgment is contrary to the universal knowledge of the
reason.

Reply Obj. 3: It is impossible for anyone to have an actual knowledge
or true opinion about a universal affirmative proposition, and at the
same time a false opinion about a particular negative proposition, or
vice versa: but it may well happen that a man has true habitual
knowledge about a universal affirmative proposition, and actually a
false opinion about a particular negative: because an act is directly
opposed, not to a habit, but to an act.

Reply Obj. 4: He that has knowledge in a universal, is hindered, on
account of a passion, from reasoning about that universal, so as to
draw the conclusion: but he reasons about another universal
proposition suggested by the inclination of the passion, and draws
his conclusion accordingly. Hence the Philosopher says (Ethic. vii,
3) that the syllogism of an incontinent man has four propositions,
two particular and two universal, of which one is of the son, e.g. No
fornication is lawful, and the other, of passion, e.g. Pleasure is to
be pursued. Hence passion fetters the reason, and hinders it from
arguing and concluding u