MAN is the talkative animal. All other definitions lead up to or away from this crucial talent for speech. Man stands erect and looks at the stars. The posture is awkward and requires a great increase of mental control. Even the fifteen degrees of difference between man and gorilla seem to require more than double mental capacity. With this increase of brain goes the increase of those frontal areas on which man depends for the co-ordination and reproduction of speech-sounds. Man invents, thanks to his opposable thumbs; but chimpanzees would be twice as inventive if they could communicate their inventions by speech. In gregariousness, sociability, or political efficiency man is perhaps less competent than wolves, bees, or ants, if we measure means and ends, but man alone can alter his polity by discussion. Man is rational; his reasons are recorded in his language along with his unreason, his emotionalism, and his subconscious urges (so far as these can be known). Man has a history; but knows it only because of speech, not merely in rudimentary forms, but as an art of oral or written record, and by means of language he knows his own history and that of animals and material things. The higher apes have most of the organs of speech, and a chimpanzee or gorilla is said to have been educated to the point of greeting Florida friends by the exclamation Hi! But there is no evidence that the animal made the discovery of speech for himself, nor does his conversation seem to have much variety. The apes use a visual intelligence and follow what they see. They locate sounds only imperfectly, pay no attention to speech symbols, but are capable of establishing routine reactions to sounds and understand their owners as dogs do. This understanding is of the broadest kind and easily surrendered; it is bound by routine and cannot be voluntarily reproduced.
This supreme human characteristic, however, is not due to a primary endowment of speech. The brain seems primarily concerned with the co-ordination of movements; it receives stimuli, reacts, and issues orders. The nose, windpipe, lungs, and diaphragm inhale and exhale breath. The teeth tear food which the tongue