ned in the responsive behaviour,
from the viscera and vaso-motor system.

Some psychologists, however, contend that the emotional experience
is generated in the sensorium prior to, and not subsequent to, the
behaviour-response and the visceral disturbances. It is a direct and not
an indirect outcome of the presentation to the special senses. Be
this as it may, there is a growing tendency to bring into the closest
possible relation, or even to identify, instinct and emotion in their
primary genesis. The central core of all such interpretations is that
instinctive behaviour and experience, its emotional accompaniments, and
its expression, are but different aspects of the outcome of the
same organic occurrences. Such emotions are, therefore, only a
distinguishable aspect of the primary tissue of experience and exhibit
a like differentiation. Here again a biological foundation is laid for a
psychological doctrine of the mental development of the individual.

The intimate relation between emotion as a psychological mode of
experience and expression as a group of organic conditions has an
important bearing on biological interpretation. The emotion, as the
psychological accompaniment of orderly disturbances in the central
nervous system profoundly influences behaviour and often renders it more
vigorous and more effective. The utility of the emotions in the struggle
for existence can, therefore, scarcely be over-estimated. Just as
keenness of perception has survival-value; just as it is obviously
subject to variation; just as it must be enhanced under natural
selection, whether individually acquired increments are inherited
or not; and just as its value lies not only in this or that special
perceptive act but in its importance for life as a whole; so the
vigorous effectiveness of activity has survival-value; it is subject
to variation; it must be enhanced under natural selection; and its
importance lies not only in particular modes of behaviour but in its
value for life as a whole. If emotion and its expression as a congenital
endowment are but different aspects of the same biological occurrence;
and if this is a powerful supplement to vigour effectiveness and
persistency of behaviour, it must on Darwin's principles be subject to
natural selection.

If we include under the expression of the emotions not only the
premonitory symptoms of the initial phases of the organic and mental
state, not only the signs or conditions of ha