it possible for him to dwell in harmony and co-operation with
large groups of his fellows.

We, the lineal representatives of the successful enactors
of one scene of slaughter after another, must, whatever more
pacific virtues we may also possess, still carry about with
us, ready to burst at any moment into flame, the smouldering
and sinister traits of character by means of which they lived
through so many massacres, harming others, but themselves
unharmed.... If evolution and the survival of the fittest
be true at all, the destruction of prey and of human rivals
must have been among the most important of man's primitive
functions, the fighting and the chasing instincts _must_ have
become ingrained. Certain perceptions _must_ immediately,
and without the intervention of inferences and ideas, have
prompted emotions and motor discharges; and both the latter
must, from the nature of the case, have been very violent, and
therefore when unchecked of an intensely pleasurable

kind. It is just because bloodthirstiness is such a primitive
part of us that it is so hard to eradicate, especially where a
fight or a hunt is promised as a part of the fun.... No! those
who try to account for this from above downwards, as if it
resulted from the consequences of the victory being rapidly
inferred, and from the agreeable sensations associated with
them in the imagination, have missed the root of the matter.
Our ferocity is blind and can only be explained from _below_.
Could we trace it back through our lines of descent, we
should see it taking more and more the form of a fatal reflex
response, and at the same time becoming more and more the pure
and direct emotion that it is.[157]

If we examine, in fact, our pleasures and pains, our moments of
elation and depression, we find that they go back for the most part to
instincts developed in the struggle for food and rivalry for mates.
We can perhaps best get at the meaning of the conflict interest to the
organism in terms of the significance to itself or the organism's own
movements. Locomotion, of whatever type, is primarily to enable the
animal to reach and grasp food, and also to escape other animals
bent on finding food. The structure of the organism has been built
up gradually through the survival of the most efficient structures.
Corresponding with a structure mechanically ad