THE EVOLUTION OF THE BRAIN
one who is capable of comparing his past and future actions or motives, and of approving or disapproving of them. We have no reason to suppose that any of the lower animals have this capacity; therefore, when a Newfoundland dog drags a child out of the water or a monkey faces danger to rescue its comrade or takes charge of an orphan monkey we do not call its conduct moral.” If this be admitted it follows that one of the essential conditions for the display of moral qualities depends upon the integrity of certain parts of the brain, without which it would not be possible to recall the past or to speculate about the future. Memory and foresight do not, of course, confer moral qualities, but they do represent conditions essential for the display of such humanitarian attributes.
Only during the last century has any accurate information been acquired as to which parts of the brain are concerned with the intellectual functions. Even at the present moment the terrible effects of the damage inflicted upon the brains of patients suffering from what is popularly known as “sleeping sickness” are opening new vistas of knowledge as to the parts of the brain upon whose activities personality, the sentiments and emotions, muscular skill, and intellectual and moral capabilities depend. In scores of patients, during the last five years, physicians have witnessed the most profound changes in character and morals when this insidious disease has destroyed certain small areas of the brain.
Three centuries before the beginning of the Christian era some of the wise men of Greece already recognised in the brain the real organ of the mind; yet it was reserved for modern times to confirm the accuracy of this early knowledge and to extend it. In olden times the seat of the understanding was placed in the heart, as every reader of the Old Testament must be aware, although certain passages in the
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