Life and death

by A. Dastre

Physico-chemical Theory of Life.—Iatro-mechanism.—Descartes, Borelli.—Iatro-chemistry.—Sylvius le Boë.—The Physico-chemical Theory of Life.—Matter and Energy.—Heterogeneity is merely the result of the arrangement or combination of homogeneous bodies.—Reservation relative to the world of thought.—The Kinetic Theory.

The unicist or monistic doctrine gives us a third way of conceiving the functional activity of the living being, by levelling and blending its three forms of activity—spiritual, vital, and material. It was expressed in the seventeenth and eighteenth centuries in “iatro-mechanism” and “iatro-chemistry,” conceptions to which have more recently succeeded the physico-chemical doctrine of life, and finally “current materialism.”

Materialism is not only a biological interpretation; it is a universal interpretation applicable to the whole of nature, because it is based on a determinate conception of matter. Here we find ourselves confronted by the eternal enigma discussed by philosophers relative to this fundamental problem of force and matter. We know what answers were given to the problem by the Ionic philosophers—Thales, Democritus, Heraclitus, and Anaxagoras, who discarded the agency of every spiritual power external to matter. The explanation of the world, the explanation of life, were reduced to the play of physical or mechanical forces. Epicurus, a little later, maintained that the knowledge of matter and its different forms accounts for all phenomena, and therefore for those of life.

Descartes, sharply separating the metaphysical world—that is to say, the soul defined by its attribute, thought—from the physical or material world characterized by extension, practically came to the same conclusions as the materialists of antiquity. To him, as to them, the living body was a mere machine.

Iatro-mechanism. Descartes. Borelli.—This, then, is the theory of the iatro-mechanicians, of which we may consider Descartes the founder, instead of the Greek philosophers. These ideas held their own for two centuries, and were productive of such fruitful results in the hands of Borelli, Pitcairn, Hales, Bernoulli, and Boerhaave, as to justify the jest of Bacon that “the philosophy of Epicurus had done less harm to science than that of Plato.” The iatro-mechanic school tenaciously held its own until Bichat came upon the scene.

Iatro-chemistry. Sylvius le Boë.—It was from a reaction against their exaggerations that Stahl created animism, and the Montpellier school created vitalism. We gather some idea of the extravagant character of their explanations by reading Boerhaave. To this celebrated doctor the muscles were springs, the heart was a pump, the kidneys a sieve, and the secretions of the glandular juices were produced by pressure; the heat of the body was the result of the friction of the globules of blood against the walls of the blood-vessels; it was greater in the lungs because the vessels of the lungs were supposed to be narrower than those of other organs. The inadequacy of these explanations suggested the idea of completing them by the aid of the chemistry which was then springing into being. This chemistry, rudimentary as it was, longed for a share in the government of living bodies and in the explanation of their phenomena. Distillations, fermentations, and effervescences are now seen to play their rôle, a rôle which was premature and carried to excess. Iatro-chemistry from the general point of view is only an aspect of iatro-mechanics; but it is also an auxiliary. Sylvius le Boë and Willis were its most eminent representatives. This theory remained in the background until chemistry made its great advance—that is to say, in the days of Lavoisier. After that, its importance has gradually increased, particularly in the present day. Nowadays, the general tendency is to regard the organic functional activity, or even morphogeny—i.e., whatever there is that is most peculiar to and characteristic of living beings—as a consequence of the chemical composition of their substance. This is a point of capital importance, and to it we must recur.

The Physico-chemical Theory of Life.—Contemporary biological schools have made many efforts to secure themselves from any slips on the philosophical side. They have avoided in most cases the psychological problem; they have deliberately refrained from penetrating into the world of the soul. Hence, the physico-chemical theory of life has been built up free from spiritualistic difficulties and objections. But this prudence did not exclude the tendency. And there is no doubt, as Armand Gautier said, that “real science can affirm nothing, but it also can deny nothing outside observable facts;” and again, that “only a science progressing backwards can venture to assert that matter alone exists, and that its laws alone govern the world.” It is none the less true that by establishing the continuity between inert matter and living matter, we thereby render probable the continuity between the world of life and the world of thought.

Matter and Energy.—Besides, and without any wish to enter into this burning controversy, it is only too evident that there is no agreement as to the terms that are used, and in particular as to “matter” and “laws of matter.” It is not necessary to repeat that the geometrical mould in which Descartes cast his philosophy has long since been broken. The celebrated philosopher, in defining matter by one attribute—extension, does not enable us to grasp its activity, an activity revealed by all natural facts; and in defining the soul by thought alone, prevents us from seeking in it the principle of this material activity. This purely passive matter, consisting of extension alone, this bare matter was to Leibniz a pure concept. A philosopher of our own time, M. Magy, has called it a sensorial illusion. The bodies of nature exhibit to us matter clad with energy, formed by the indissoluble union of extension with an inseparable dynamical principle. The Stoics declared that matter is mobile and not immobile, active and not inert. Leibniz also had this in his mind when he associated it indissolubly with an active principle, an “entelechy.” Others have said that matter is “an assemblage of forces,” or with P. Boscovitch, “a system of indivisible points without extension, centres of force, in fact.” Space would be the geometrical locus of these points.

In this conception the materialistic school finds the explanation of all phenomenality. Physical properties, vital phenomena, psychical facts, all have their foundation in this immanent activity. Material activity is a minimum of soul or thought which, by continuous gradation and progressive complexity, without solution of continuity, without an abrupt transition from the homogeneous to the heterogeneous, rises through the series of living beings to the dignity of the human soul. The observation of the transitions, an imperfect tracing of the geometrical method of limits, thus enables us to pass from material to vital, and from thence to psychical activity.

Apparent Heterogeneity is the Result of the Arrangement or the Combination of Homogeneous Bodies.—In this system, material energy, life, soul would only be more and more complex combinations of the consubstantial activity with material atoms. Life appears distinct from physical force, and thought from life, because the analysis has not yet advanced far enough. Thus, glass would appear to the ancient Chaldeans distinct from the sand and salt of which they made it. In the same way, again, water, to modern eyes, is distinct from its constituents, oxygen and hydrogen. The whole difficulty is that of explaining what this “arrangement” of the elements can introduce that is new in the aspect of the compound. We must know what novelty and apparent homogeneity the variety of the combinations, which are only special arrangements of the elementary parts, may produce in the phenomena. But we do not know, and it is this ignorance which leads us to consider them as heterogeneous, irreducible, and distinct in principle. The vital phenomenon, the complexus of physico-chemical facts, thus appears to us essentially different from those facts, and that is why we picture to ourselves “dominants” and “directing forces” more or less analogous to the sidereal guiding principle of Kepler, which, before the discovery of universal attraction, regulated the harmony of the movements of the planets.