he following attitudes "I expect there will be an egg for breakfast";
"I remember there was an egg for breakfast"; "Was there an egg for
breakfast?" "An egg for breakfast: well, what of it?" "I hope there
will be an egg for breakfast"; "I am afraid there will be an egg for
breakfast and it is sure to be bad." I do not suggest that this is a
list of all possible attitudes on the subject; I say only that they
are different attitudes, all concerned with the one content "an egg for
breakfast."

These attitudes are not all equally ultimate. Those that involve desire
and aversion have occupied us in Lecture III. For the present, we are
only concerned with such as are cognitive. In speaking of memory, we
distinguished three kinds of belief directed towards the same
content, namely memory, expectation and bare assent without any
time-determination in the belief-feeling. But before developing this
view, we must examine two other theories which might be held concerning
belief, and which, in some ways, would be more in harmony with a
behaviourist outlook than the theory I wish to advocate.

(1) The first theory to be examined is the view that the differentia of
belief consists in its causal efficacy I do not wish to make any author
responsible for this theory: I wish merely to develop it hypothetically
so that we may judge of its tenability.

We defined the meaning of an image or word by causal efficacy, namely by
associations: an image or word acquires meaning, we said, through having
the same associations as what it means.

We propose hypothetically to define "belief" by a different kind
of causal efficacy, namely efficacy in causing voluntary movements.
(Voluntary movements are defined as those vital movements which are
distinguished from reflex movements as involving the higher nervous
centres. I do not like to distinguish them by means of such notions as
"consciousness" or "will," because I do not think these notions, in any
definable sense, are always applicable. Moreover, the purpose of the
theory we are examining is to be, as far as possible, physiological and
behaviourist, and this purpose is not achieved if we introduce such a
conception as "consciousness" or "will." Nevertheless, it is necessary
for our purpose to find some way of distinguishing between voluntary and
reflex movements, since the results would be too paradoxical, if we were
to say that reflex movements also involve beliefs.) According to this
definiti