eir constituent elements? When the brain is active, there are, to be
sure, certain material products which pass into the blood and are
finally eliminated from the body; but among these products no one would
be more surprised than the materialist to discover pains and pleasures,
memories and anticipations, desires and volitions. This talk of
thought as a "secretion" we can afford to set aside.

Nor need we take much more seriously the seemingly more sober statement
that thought is a "function" of the brain. There is, of course, a
sense in which we all admit the statement; minds are not disembodied,
and we have reason to believe that mind and brain are most intimately
related. But the word "function" is used in a very broad and loose
sense when it serves to indicate this relation; and one may employ it
in this way without being a materialist at all. In a stricter sense of
the word, the brain has no functions that may not be conceived as
mechanical changes,--as the motion of atoms in space,--and to identify
mental phenomena with these is inexcusable. It is not theoretically
inconceivable that, with finer senses, we might directly perceive the
motions of the atoms in another man's brain; it is inconceivable that
we should thus directly perceive his melancholy or his joy; they belong
to another world.

56. SPIRITUALISM.--The name _Spiritualism_ is sometimes given to the
doctrine that there is no existence which we may not properly call mind
or spirit. It errs in the one direction as materialism errs in the
other.

One must not confound with this doctrine that very different one,
Spiritism, which teaches that a certain favored class of persons called
mediums may bring back the spirits of the departed and enable us to
hold communication with them. Such beliefs have always existed among
the common people, but they have rarely interested philosophers. I
shall have nothing to say of them in this book.

There have been various kinds of spiritualists. The name may be
applied to the idealists, from Berkeley down to those of our day; at
some of the varieties of their doctrine we have taken a glance
(sections 49, 53). To these we need not recur; but there is one type
of spiritualistic doctrine which is much discussed at the present day
and which appears to appeal strongly to a number of scientific men. We
must consider it for a moment.

We have examined Professor Clifford's doctrine of Mind-stuff (section
43). Cliff