to anatomy, physiology, and natural history, and profound speculations into man's psychical nature. No study that throws light on the nature and constitution of life and mind is foreign to medicine. Anatomy is its substratum; knowledge of brain and mind its superstructure. For that reason the advent of Aristotle, the great Stagirite, as he was called, upon life's stage in Greece was a most fortunate event. It was he who gave an impetus to the inductive school of philosophy, which, as we have seen, was beginning to wane under the sway of the dogmatic school of medicine.

Aristotle was born in Thrace, on the western side of the Gulf of Strymon, three hundred and sixty years B. C., one hundred years after the birth of Hippocrates. His father, Nichomachus, was distinguished in the profession of medicine, which gave the son a bias to that art. He, Aristotle, is said to have been one of the most illustrious philosophers of antiquity, "and, if considered in respect of intellect alone, perhaps was the most remarkable man that ever lived." I To him we owe the first treatise on

Anatomy.

His medical biographers, for the most part, pass him by with a paragraph or two, yet he did more to advance the science and enlarge the scope of medicine than any man since Hippocrates; more to advance the knowledge of man-not so much of man as so many pounds of flesh and bone Thomas's Biographical Dictionary.

and blood, but as a living personality; and because they have failed to comprehend him, many writers question whether his influence on medicine "has not been unfavorable to the progress of knowledge." Yet, "so great was the ascendancy which this genius acquired over the minds of men for many centuries after his death, that all his opinions, the most unfounded as well as the most philosophical, were indiscriminately received as established truths, which no one ventured to oppose or to controvert." 2

We may be pardoned, perhaps, for making an attempt to interpret for the benefit of our readers the dynamic or psychical philosophy of this rare sage, who, strange to say, after the lapse of twenty-three hundred years, seems to need an interpreter.

Aristotle is the first man in antiquity to conceive and put forth the idea of the unity of the universe; the unity of matter and force; the unity of physical and psychical; the substantial oneness, monism, of body and soul, force and substance.

Aristotle advanced a new term, yux, anglicised psyché, from which our term psychology is derived. "It is the efficient, the final, and the formal cause of the body," he writes. In modern phraseology, it is the animating, immanent intelligence of sentient beings. It is man's conscious life, intellection, due to cerebration or brain 1 Bostock, op. cit.

Le Clerc, par. I, lib. ii., ch. 4.

function. It is to the cerebro-spinal system what qúots (physis) is to the grand sympathetic system: ψυχή thinks and knows; φύσις feels and knows. The latter has no need of thinking-of processes of intellection. It knows without thinking, and carries on the operations of the material, animated world without any conception of the end toward which it works; such, for example, as digestion, assimilation, growth, and conservation of animal life; and in lower nature the harvests, budding, blossoming, and maturity of plants; intelligent processes all, but unconscious. So it is in the animal kingdom: the coral builds its reef, unmindful of the reef; the clam forms its shell, unconscious of the shell; man builds himself a body oblivious of the process. Yet it is carried forward unerringly to perfection through all its stages, from the cradle to the grave. It is impossible for an intelligent person to question the fact; equally impossible is it for such a person to question the Intelligence with which the work is carried on; yet totally unconsciously is it done. Dúats is the animating principle of Hippocrates; and what he meant by Physis (Dúos) is related to the Pneuma (Пvɛūμ¤) of Galen, about which the physiologists have puzzled so much, and concealed their want of understanding by the use of such terms as gravity, nature, instinct, vitality, soul, etc.; blind, apparently, to their sublime significance! But without the presence of Aristotle's Tux, and Hippocrates' Pústs, the

medical art is vain, and science and philosophy could have no existence.

One does not withhold his admiration and wonder at the works of engineering genius in tunnelling under the Thames or the Hudson, or throwing suspension bridges over rivers too deep for abutments, or the marvellous exploits of electricity in the industrial arts; yet none of these things can compare in marvellousness to the genius that Nature (physis) displays in knitting a bone, without hands or other implements; encysting a poisonous bullet in the body; forming pockets in which to collect and store pus in pyæmia; or incasing bacteria with tuberculin in the lungs of tuberculosis cases, in order to stay its ravages and to prolong the life of the victims. The process of one belongs to the sphere of conscious Intellection, the Tux of Aristotle; the other to the operation of unconscious Intelligence, the Þúas of Hippocrates.

Hippocrates made use of the term physis to comprehend the Supreme Principle in the constitution of Nature; Aristotle used the term psyché to mean the same thing-and more. It is more consistent with the modern conception of the subject to keep them distinct and separable —that is, to confine the term physis to the genius of Nature, and the term psyché to the genius of Mind-mentality. But whether these principles were one or two, single or dual, they were a most important contribution to the science of medicine.

Art could not draw a blister, heal a cut, cure a laceration, knit a broken bone, produce emesis, or correct a sepsis, in the absence of this Force, or these Forces.

One may justly question the wisdom of a too close adherence to hypotheses and theories in medicine; but it should not be forgotten or overlooked that both theory and hypotheses have their place in science and philosophy. The ultimate atom of Dalton is an hypothesis, but it is the basis of modern chemistry and the splendid achievements of that science. The idea of Newton, of the universality of ether, is still an hypothesis; but the laws of optics and wireless telegraphy are predicated on it. It is an admirable working hypothesis, but the truth of it has never been demonstrated. Every man of strong intellect must theorize on matters which he conceives but cannot prove.

We must insist, therefore, that Celsus was not wholly wrong when he declared that "without a knowledge of the nature of disease no one is qualified to treat it," certainly not, along lines of scientific and demonstrable procedures. Nevertheless, in the absence of knowledge, the method of the Empiric is justifiable. No one can have failed to observe that among the greatest philosophers of antiquity may be found the greatest theorizers. And when Aristotle declared that "the philosopher should end with medicine, the physician should begin with philosophy," he uttered a great truth