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

You can mark in desire the rising of the tide, as the appetite more and more invades the personality, appealing, as it does, not merely to the sensory side of the self, but to its ideal components as well.

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.

It may be added, to prevent misunderstanding, that when I speak of contemplated objects in this last phrase as objects of contemplation, the act of contemplation itself is of course an enjoyment.

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

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

An object is not first imagined or thought about and then expected or willed, but in being actively expected it is imagined as future and in being willed it is thought.