A useful analogy for understanding the nature of consciousness is that of a painting. The picture itself corresponds to the contents of consciousness; the canvas on which it is painted corresponds to the faculty of consciousness. An infinite variety of pictures can be painted on the canvas; but whatever the pictures, they all share the fact that they are painted on a canvas. Without the canvas there would be no painting.
The pictures that are painted on the canvas of consciousness take many forms. They include our perceptions of the world around, our thoughts, our ideas, our beliefs, our values, our feelings, our emotions, our hopes, our fears, our intuitions, our dreams and fantasies -- and more. But none of this would be possible if we did not in the first place possess the capacity for consciousness. Without it there would be no subjective experience of any kind.
Excerpt from: The Evolution of Consciousness by Peter Russell