The only difference between image and idea is thus that in the one case, the expression of the object is confused, and in the other, it is clear. The confusion comes from this: every movement envelops in itself the infinity of the movements of the universe; and the brain receives an infinity of modifications to which only a confused thought can correspond, enveloping the infinity of clear ideas that would correspond to each detail. Clear ideas are therefore contained in the confused ideas. They are unconscious; they are perceived without being apperceived. Only their sum total is apperceived; this appears simple to us because of our ignorance of its components.