o Job 33:15, 16, "By a
dream in a vision by night, when deep sleep is wont to lay hold of
men [*Vulg.: 'When deep sleep falleth upon men.' St. Thomas is
apparently quoting from memory, as the passage is given correctly
above, Q. 95, A. 6, Obj. 1.] . . . Then He openeth the ears of men,
and teaching instructeth them in what they are to learn." Therefore a
man, while asleep, can act according to or against his reason, and
this is to do good or sinful actions, and thus it seems that
nocturnal pollution is a sin.

_On the contrary,_ Augustine says (Gen. ad lit. xii, 15): "When the
same image that comes into the mind of a speaker presents itself to
the mind of the sleeper, so that the latter is unable to distinguish
the imaginary from the real union of bodies, the flesh is at once
moved, with the result that usually follows such motions; and yet
there is as little sin in this as there is in speaking and therefore
thinking about such things while one is awake."

_I answer that,_ Nocturnal pollution may be considered in two ways.
First, in itself; and thus it has not the character of a sin. For
every sin depends on the judgment of reason, since even the first
movement of the sensuality has nothing sinful in it, except in so far
as it can be suppressed by reason; wherefore in the absence of
reason's judgment, there is no sin in it. Now during sleep reason has
not a free judgment. For there is no one who while sleeping does not
regard some of the images formed by his imagination as though they
were real, as stated above in the First Part (Q. 84, A. 8, ad 2).
Wherefore what a man does while he sleeps and is deprived of reason's
judgment, is not imputed to him as a sin, as neither are the actions
of a maniac or an imbecile.

Secondly, nocturnal pollution may be considered with reference to its
cause. This may be threefold. One is a bodily cause. For when there
is excess of seminal humor in the body, or when the humor is
disintegrated either through overheating of the body or some other
disturbance, the sleeper dreams things that are connected with the
discharge of this excessive or disintegrated humor: the same thing
happens when nature is cumbered with other superfluities, so that
phantasms relating to the discharge of those superfluities are formed
in the imagination. Accordingly if this excess of humor be due to a
sinful cause (for instance excessive eating or drinking), nocturnal
pollution has the character of sin from its