VII. The Beginnings of Sex Duality

The organs of motion were at that time man's most highly developed organs. The sense-organs of to-day were then quite unevolved. The most advanced were the organ of hearing and the organs for the perception of cold and heat (the sense of feeling); still far behind was the perception of light. Man was born with the senses of hearing and of touch, and then, somewhat later, the light-perception was evolved.