In the infant's mind the arrival of a sense-impression arouses only a perception, a consciousness of the sense-impression. In the mind of any other
person it awakens not only this present consciousness but also the associated memories of past experiences.
The Indelible Impress
Upon the slumbering mind of the newborn babe the very first message from the sense-organs leaves its exquisite but indelible impress. The next sense-perception is but part of a state of consciousness, in which the memory of the first sense-perception is an active factor. This is a higher type of mental activity. It is a something other and more complex than the mere consciousness of a sensory message and the decision as to its source.
The moment, then, that we get beyond the first crude sense-perception consciousness consists not of detached sensory images but of "ideas," the complex
product of present sense-perceptions, past sense-perceptions and the mental processes known to psychology as association and discrimination.
How Ideas are Created
Every concrete conception or idea, such as "horse," "rose," "mountain," is made up of a number of associated properties. It has mass, form and various degrees of color, light and shade. Every quality it possesses is represented by a corresponding visual, auditory, tactual or other sensation.
Thus, your first sense-perception of coffee was probably that of sight. You perceived a brown liquid and your causal judgment explained that this sense-perception was the result of something outside of your body. Standing alone, this causal judgment meant very
little to you, so far as your knowledge of coffee was concerned. So also the causal judgment that traced your sense of the smell of coffee to some object in space meant little until it was added to and associated with your eye-vision of that same point in space. And it was only when the causal judgment explaining the taste of coffee was added to the other two that you had an "idea" of what coffee really was.