periment that a difference may be so small that it seems to the observer entirely imperceptible, and yet it will be correctly given by guessing more than half the time, or that an impression which entirely escapes consciousness the first time may become apparent by repetition. Sub-consciousness is thus correlated with distinct consciousness.
21. The idea of mental extensity is important in ethics.
Pleasures and pains differ not only in time and intensity, but also in extensity. More mental elements are involved in some feelings than in others. A pleasure (e.g., eating) may be intense, but not extensive. Another (e.g., doing one's daily duty) is not intense, but it is massive. An infant crying may suffer intense pain, in fact it is all pain, but the pain is not extensive because the mind is 'small.' With greater mental development the intensity of feelings may be less, but their extensity is greater. The idea of mental complexity throws light on the nature of emotions, in which some elements are in pleasure, some in pain. Through the phenomena of choice, and through our moral judgments, the extensity of pleasures and pains is correlated with their intensity, and duration. The greatness of a pleasure is the product of its extensity, intensity, and duration. What writers on morals mean by higher and lower pleasures is thus explained without mysticism. The idea of extensity of feeling reaches beyond the individual. Those pleasures (e.g., creation in art and science, or love) are the greatest which affect many elements in the individual, and extend to other individuals, being at the same time intense and enduring.
J. McKeen Cattell.
Columbia College.
