Page:Popular Science Monthly Volume 27.djvu/89

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THE NERVOUS SYSTEM AND CONSCIOUSNESS.
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mistake who attempt to deal with the physiological materialism of our day by citing the American crow-bar case, or any number of cases of brain-loss unaccompanied by marked intellectual enfeeblement. It is equally puerile to cite instances of small brains with great intellectual power. In the first place, these small brains may be of superior quality, as small muscles often are; or, in the second place, the boasted greatness of mind may be anything and everything but greatness of mind. Learning of a very extensive kind may coexist with small mental caliber. A monkey is shrewd and quick, and cunning and smart a parrot is learned, up in a variety of languages, speaking, as many human parrots do, some French, some Italian, some Spanish: there is no great-mindedness here.

Proof from size of the brain is, on the whole, reliable. There is, in general, a remarkable decrease in weight corresponding to the intellectual enfeeblement. Many idiots between the ages of sixteen, forty, and fifty years, have shown brains weighing 193/4, 253/4, and 221/2 ounces. There is on record the case of a deaf-mute idiot, forty-three years old, who showed an idiocy of the lowest kind, yet his brain weighed over forty-eight ounces. Such cases are not to overthrow an induction based upon a large majority of opposing instances.

It remains for the succeeding paper to consider the question propounded by the physiology of to-day, respecting the kind of relation which holds between the brain and consciousness. If we were to accept the judgment of the younger leading physicians, we should believe that modern Physiology had answered her own question. A distinguished physician of my city says, in his published "Lectures on Physiology": "The so-called voluntary movements are only the final responses to impressions made upon the special senses at the time or in the past. The highest expressions of the intellect of man may be resolved into the more perfect transmutations of outside forces, by machinery made more perfect by original constitution or by labor."

Without believing that such a correlation between brain and consciousness as is here asserted can be rationally accepted, there are, as I think, two general conclusions which may be drawn with certainty:

A constant relation obtains between nerve-matter and those manifestations which are usually said to belong to the soul. This relation is so important, so constant, as to determine in large measure the intellectual and moral well-being of every individual.

The origination of our states of consciousness, their character and conduct, are conditioned by physical processes antecedently occurring in the brain.