In the marsupials it is more evident, and its excitation by electric currents evokes movements in the musculature of the crossed side of the body.
Stimulants are those which lead to excitation of the mental faculties and in quantity may lead to delirium and incoherence.
To what peculiar excitation of our bodily or mental organism, it is asked, are the emotions due which make us declare an object beautiful or sublime?
In this adjustment the lowest stage is taken by 'reflex action and instinct, where Spencer the change of the organs is purely automatic. As the external complexity increases, this automatic regularity fails; there is only an incipient excitation of the nerves.
It is when the excitation is partial only, when it does not inevitably and immediately appear as action, that we have the appearance of intellect in the gap. The chief and fundamental difference between Schopenhauer and Spencer lies in the refusal of the latter to give this "adjustment" or "automatic action" the name of will.