236 THE FEELINGS AND EMOTIONS 
correlative in consciousness of the behaviour of the nervous 
system under stimulation. Let us take some simple case such 
as that, for example, of a hungry chick pecking at a grain of 
corn. This is explained from the physiological point of view 
by saying that internal and external stimulation—internal from 
the digestive organs and system in need of food, external 
through the eye—gives rise to a state of unstable equilibrium 
in the nerve-centres ; and that, when the instability reaches a 
certain value, the nervous system discharges into the motor 
organs, the chick pecks, and stable equilibrium is restored. 
The tendency to discharge in some way under stimulation is 
an essential characteristic of a nervous system. It is one of 
the facts of physiological science. So, too, the conative 
tendency is one of the facts of psychological science ; it is a 
change in the situation introduced by the effects of the physio- 
logical discharge. : 
Let us here parenthetically notice that the physiological 
tendency in the nervous system is an evolved complication and 
a specialized development of one of the fundamental properties 
of protoplasm—that which is often spoken of as irritability. 
One of the characteristics of all living matter is its ‘‘ explosive” 
instability. So that at the very threshold of organic behaviour 
we have the analogue of that which, in its developed form, 
becomes the tendency of the nervous system to discharge as 
the result of stimulation. The conative tendency of the 
psychologist, therefore, has its roots deep down in the elemental 
germs of all organic life. 
And this conative tendency is, says Dr. Stout, not only a 
fact but an experience. Let us return to our hungry chick 
that pecks at a grain of corn. And let us grant that as the 
result of stimulation there arise states of consciousness which 
we describe as a feeling of hunger and the sight of the grain 
of corn. The nervous system now discharges ; and there are 
introduced into the situation a further group of data, the 
motor consciousness of the actual behaviour, sensory data 
from the results of the act, the seizing of the grain and so 
forth. The situation has unquestionably changed. But ig 
