The sensory acts are accordingly distinguished by their objects.

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

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

We cannot therefore say that mental acts contain a cognitive as well as a conative element.

But though cognition is not an element of mental action, nor even in any real sense of the word an aspect of it, the distinction of cognition and conation has if properly defined a definite value.

In the perception of a tree we can distinguish the act of experiencing, or perceiving, from the thing experienced, or perceived.

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.