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

An expectation is a future object, recognised as belonging to me.

The sensory acts are accordingly distinguished by their objects.

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.

For psychological purposes the most important differences in conation are those in virtue of which the object is revealed as sensed or perceived or imaged or remembered or thought.

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.

When we come to images or memories or thoughts, speculation, while always closely related to practice, is more explicit, and it is in fact not immediately obvious that such processes can be described in any sense as practical.