of being exhibited in actions, for it
is only the actions of animals that we can observe. They MAY have minds
in which all sorts of things take place, but we can know nothing about
their minds except by means of inferences from their actions; and the
more such inferences are examined, the more dubious they appear. It
would seem, therefore, that actions alone must be the test of the
desires of animals. From this it is an easy step to the conclusion that
an animal's desire is nothing but a characteristic of a certain series
of actions, namely, those which would be commonly regarded as inspired
by the desire in question. And when it has been shown that this view
affords a satisfactory account of animal desires, it is not difficult
to see that the same explanation is applicable to the desires of human
beings.

We judge easily from the behaviour of an animal of a familiar
kind whether it is hungry or thirsty, or pleased or displeased, or
inquisitive or terrified. The verification of our judgment, so far
as verification is possible, must be derived from the immediately
succeeding actions of the animal. Most people would say that they infer
first something about the animal's state of mind--whether it is hungry
or thirsty and so on--and thence derive their expectations as to its
subsequent conduct. But this detour through the animal's supposed mind
is wholly unnecessary. We can say simply: The animal's behaviour during
the last minute has had those characteristics which distinguish what
is called "hunger," and it is likely that its actions during the next
minute will be similar in this respect, unless it finds food, or is
interrupted by a stronger impulse, such as fear. An animal which is
hungry is restless, it goes to the places where food is often to be
found, it sniffs with its nose or peers with its eyes or otherwise
increases the sensitiveness of its sense-organs; as soon as it is near
enough to food for its sense-organs to be affected, it goes to it with
all speed and proceeds to eat; after which, if the quantity of food has
been sufficient, its whole demeanour changes it may very likely lie
down and go to sleep. These things and others like them are observable
phenomena distinguishing a hungry animal from one which is not hungry.
The characteristic mark by which we recognize a series of actions
which display hunger is not the animal's mental state, which we cannot
observe, but something in its bodily behaviour; it is thi