k
that the complexity of consciousness insensibly diminishes also. But
if we make a jump, say to the tunicate mollusks, we see no reason there
to infer the existence of consciousness at all. Yet not only is it
impossible to point out a place where any sudden break takes place, but
it is contrary to all the natural training of our minds to suppose a
breach of continuity so great."

We must not, says Clifford, admit any breach of continuity. We must
assume that consciousness is a complex of elementary feelings, "or
rather of those remoter elements which cannot even be felt, but of
which the simplest feeling is built up." We must assume that such
elementary facts go along with the action of every organism, however
simple; but we must assume also that it is only when the organism has
reached a certain complexity of nervous structure that the complex of
psychic facts reaches the degree of complication that we call
Consciousness.

So much for the assumption of something like mind in the mollusk, where
Clifford cannot find direct evidence of mind. But the argument does
not stop here: "As the line of ascent is unbroken, and must end at last
in inorganic matter, we have no choice but to admit that every motion
of matter is simultaneous with some . . . fact or event which might be
part of a consciousness."

Of the universal distribution of the elementary constituents of mind
Clifford writes as follows: "That element of which, as we have seen,
even the simplest feeling is a complex, I shall call _Mind-stuff_. A
moving molecule of inorganic matter does not possess mind or
consciousness; but it possesses a small piece of mind-stuff. When
molecules are so combined together as to form the film on the under
side of a jellyfish, the elements of mind-stuff which go along with
them are so combined as to form the faint beginnings of Sentience.
When the molecules are so combined as to form the brain and nervous
system of a vertebrate, the corresponding elements of mind-stuff are so
combined as to form some kind of consciousness; that is to say, changes
in the complex which take place at the same time get so linked together
that the repetition of one implies the repetition of the other. When
matter takes the complex form of a living human brain, the
corresponding mind-stuff takes the form of a human consciousness,
having intelligence and volition."

This is the famous mind-stuff doctrine. It is not a scientific
doctrine, for i