It seems that we notice through a double process in which the first factor is a choice of what is interesting or important. The second factor, working simultaneously with the first, is that we need a notation for almost anything that can be noticed. Notation is a system of symbols—words, numbers, signs, simple images (like squares and triangles), musical notes, letters, ideographs (as in Chinese), and scales for dividing and distinguishing variations of color or of tones. Such symbols enable us to classify our bits of perception. They are the labels on the pigeonholes into which memory sorts them, but it is most difficult to notice any bit for which there is no label. Eskimos have five words for different kinds of snow, because they live with it and it is important to them. But the Aztec language has but one word for snow, rain, and hail. What governs what we choose to notice? The first (which we shall have to qualify later) is whatever seems advantageous or disadvantageous for our survival, our social status, and the security of our egos. The second, again working simultaneously with the first, is the pattern and the logic of all the notation symbols which we have learned from others, from our society and our culture. It is hard indeed to notice anything for which the languages available to us (whether verbal, mathematical, or musical) have no description. This is why we borrow words from foreign languages. There is no English word for a type of feeling which the Japanese call yugen, and we can only understand by opening our minds to situations in which Japanese people use the word.1