psychologist holds that the material conditions of mind are of supreme importance to the understanding of its laws. To the metaphysician the brain is a thing of but little interest, which lie contentedly leaves to the phrenologist, or he avoids it as opening the dangerous way to materialism; the mental physiologist is attracted to brain-studies because they open the way to the largest, truth, because they elucidate the conditions of mental action, connect mind with character, explain individuality, and disclose the laws of improvement on the hitherto neglected side of human nature. Let us here note some of the differences in the practical bearings of these two methods.
If we take the phenomena of mental growth—certainly of great importance—we find that the metaphysician can give us but little help in treating it. Growth is primarily a biological conception, yet mind grows. But mental physiology, or objective psychology, taking into consideration the vital conditions, can deal rationally with psychical development. The subject of mental growth is at the root of education. To the metaphysical teacher, ventilation, exercise, clothing, and diet, as they are material concernments, are of but indifferent moment; while to the well-instructed psychological teacher they are the fundamental conditions of successful work. He knows that he can only cultivate the mind in accordance with the laws of the organism of which it is a part. To the metaphysician, mind is an independent entity in an upper sphere of being; to the mental physiologist, it is the activity of an organized mass of nerve-cells and filaments, charged with blood and carrying on processes of thinking and feeling under the laws of nutrition. If the organization is low, or perverted by hereditary taint, or if the blood is thin or impure, so that the nutritive processes are sluggish or enfeebled, he understands that the bodily growth will be hindered, and mental action correspondingly lowered in vigor.
Another illustration of the contrast of the two methods is furnished by the phenomena of insanity. To the metaphysician in all the metaphysical ages insanity was a sealed book, and by that method would have so continued to the end of time. And this, for the reason that the metaphysician can not or will not recognize in any adequate degree the dependence of psychical effects upon physiological conditions. He refuses to see that it is the brain which, in its health, carries on all the normal operations of mind. He will not have the mental and the corporeal united. He will not degrade the dignity of his subject by mixing it with base material considerations. Hence, of diseased mind and the causes and laws of its morbidity, he knew nothing, and could know nothing. It is to the physician, and not the metaphysician, to the anatomist who studied the structure of the brain, and to the physiologist who studied its functions, and the pathologist who studied its diseases, that we owe all our knowledge of that most practical of all subjects, irregular and abnormal mental action.
And now we have another interesting illustration of the contrast of these two methods of study exemplified in the able work on suicide of Dr. Morselli, noticed in our December number. It is there shown by multitudinous proofs, and it was illustrated in our notice, that the phenomena of suicide observe a regularity to which we give the name of law. But more than this, it is proved that suicidal regularity has an orderly variation—corresponding to variations of external condition—climate, season, country, age, sex, race, cultivation, and social circumstances. The question is, What is the nature of the relation? Nobody will pretend that it is accidental. Is it not, then, dynamic and causal?
Now, the metaphysician can do nothing with the problem, because his