outbreaks of fury on the part of offended or otherwise enraged
animals. I see no occasion for disturbing the commonly received
definition of instinct as given above; for those who think they can
refer all the so-called ordinary instincts of animals to conscious
deliberation ipso facto deny that there is such a thing as instinct
at all, and should strike the word out of their vocabulary. But of
this more hereafter.

Assuming, then, the existence of instinctive action as above defined,
it can be explained as -

I. A mere necessary consequence of bodily organisation. {92b}

II. A mechanism of brain or mind contrived by nature.

III. The outcome of an unconscious activity of mind.

In neither of the two first cases is there any scope for the idea of
purpose; in the third, purpose must be present immediately before the
action. In the two first cases, action is supposed to be brought
about by means of an initial arrangement, either of bodily or mental
mechanism, purpose being conceived of as existing on a single
occasion only--that is to say, in the determination of the initial
arrangement. In the third, purpose is conceived as present in every
individual instance. Let us proceed to the consideration of these
three cases.

Instinct is not a mere consequence of bodily organisation; for -

(a.) Bodies may be alike, yet they may be endowed with different