Locke’s Theory of Perception 247
are introduced to signify to mind the nature of the objects
and events in that outer world. Indeed, some of his descrip-
tions can easily be construed to mean that the mind is the in-
terior region of the skull, as for example his statement that
the mind is a dark room into which knowledge of the exter-
nal world is introduced through the windows of the sense-
organs. Despite such contentions, however, we must not al-
low ourselves to believe that Locke ever identified the mind
with parts of the body. Though mind is capable of fusion
with an organism, it remains nevertheless a distinct sub-
stance, such that if we held two great magnets on opposite
sides of a living organism, the one magnet attracting mind
and the other matter, then all the life of the organism would
be drawn out one way, and its material substance the other.
Soul would fly to one magnet, body to the other.
Having indicated briefly the relation of the mind to the
body, I shall now describe in a word or two the main proper-
ties of mind that distinguish it from matter, all of which will
have prepared us for the examination of the “what” and the
“how” of perception itself.
Perhaps the chief distinguishing trait is the kind of
“power” that mind exhibits. Locke calls it “active” power,
and contrasts it with the passive power of matter. Mind is
active, because it possesses the power to initiate movement,
whereas matter has only the power to be moved and to im-
part motion. Hence, if all matter is actually in motion, the
first cause of this cosmic motion must have been some cosmic
mind, and this is a part of Locke’s proof for the existence of
a deity. Matter could not originally have moved itself.
Mind, then, is peculiarly that kind of thing which can operate
upon another thing without itself having been mechanically
caused to do so, though even mind may have moments of
passivity during which, as we shall see, matter operates upon