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

The perceptive act is a reaction of the mind upon the object of which it is the perception.

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

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.

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.

... when demand is being destroyed by expensive oil just as expensive oil is incentivising increased production - it should come as no surprise that at some point the markets would react.