The thing of which the act of perception is the perception is experienced as something not mental.

Desire then is the invasion of the whole self by the wish, which, as it invades, sets going more and more of the psychical processes; but at the same time, so long as it remains desire, does not succeed in getting possession of the self.

Such being the nature of mental life, the business of psychology is primarily to describe in detail the various forms which attention or conation assumes upon the different levels of that life.

It is more difficult to designate this form of conation on its practical side by a satisfactory name.

But unfortunately Locke treated ideas of reflection as if they were another class of objects of contemplation beside ideas of sensation.

The mental act of sensation which issues in reflex movement is so simple as to defy analysis.

Psychology is the science of the act of experiencing, and deals with the whole system of such acts as they make up mental life.