Page:Popular Science Monthly Volume 4.djvu/572

 soul does not receive impressions from all parts of the body, but only from the brain." This truth, which now seems so elementary, was nevertheless demonstrated only by the physiology of recent times. The greatest physiological theorist of the passions, Bichat, did not accept it, as we shall see from an exposition of his doctrine.

The first physiological character recognized in the passions, by Bichat, is intermittency. Whereas our thoughts may be continued—prolonged over a considerable period of time—and whereas a habit of making the same reflections and judgments strengthens and perfects them, the passions, on the other hand, have no persistence. With the exception of that pleasure and pain which we might denominate absolute, and which depend on direct nerve-excitation, it may be asserted that a habit of the same sentiments will soon blunt and weaken them. A prolonged sensation, be it pleasant or painful, at last gives neither pleasure nor pain. The perfumer, who is ever surrounded by an odorous atmosphere, does not enjoy the sweet scents. All that delights the eye or charms the ear becomes indifferent when the impression has lasted for some time. The same holds good for disagreeable sensations. "Happiness, therefore," says Bichat, "consists only in incontinuousness. Pleasure is but a comparative sentiment, that ceases to exist where you have uniformity between present and past sensations. Were the forms of all women cast in one mould, that mould were the grave of love."

This profound difference between thought and passion Bichat explains by the theory that the former is dependent on that side of our being which we call animal life, while the latter proceeds from the organic life. Every thing that has to do with intellectual operations, properly so called, has its seat in the brain, which is the centre of animal life. Every thing that has to do with the passional states has its seat in the viscera. The effect of passion of every kind is to produce some change, some alteration in the organic life, that is to say, in the organs of circulation, of respiration, and of nutrition. This fundamental difference between intelligence and passion, as regards the organs which seem to be their respective seats, has long been remarked by popular sagacity and incorporated into language. Such expressions as "a good head," "a fine-shaped head," have always been employed to express perfection of understanding; and "a good heart," "a tender heart," to express the perfection of sentiment. It has also been a current phrase to say that the blood "boils" with anger, or that indignation "moves" the bile, or that the heart "leaps" with joy. Our gestures accord with our words: thus, when we would in dumb show indicate some state having to do with memory, imagination, perception, or judgment, we bring the hand up to the head. But, when we would express love, joy, hate, disgust, we bring the hand up to the region of the heart or of the stomach.

A close observation of facts proves the correctness of the instincts