Page:Popular Science Monthly Volume 24.djvu/785

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PHYSIOLOGICAL SIGNIFICANCE OF VITAL FORCE.
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sought to know their relations in inorganic nature, and already the evidence is prophetic of wonderful results.

In physical philosophy, "Stahlism" received its mortal wound at the close of the last century by the experiments of Rumford and Davy, which negated the theory of "caloric" and demonstrated heat to be a "mode of motion."

This new doctrine, though founded on a demonstrated fact, was not complete until 1850, when Joule, having determined the mechanical equivalent of heat and established the law of thermo-dynamics, made possible the classification of facts determined by Young, Melloni, Faraday, Liebig, Mayer, Grove, Helmholtz, Carpenter, Tyndall, Henry, and others, which enabled the deduction to be made of the universal laws of the "correlation and conservation of energy."

In inorganic nature, unity, under law, is an accepted fact, and analysis and synthesis harmonize as to causes and effects; but in the organic world there are yet many unknown quantities, and the progress in solving the mysteries of life-action is necessarily slow, because of their complex character.

To some, "vitalism" yet maintains its position in the philosophic realm of organization, and a "vital force," independent of and antagonistic to physical force, yet presides over the manifestations of organic bodies. This, if true, necessitates "two distinct sciences and two disinct orders in nature," which, though related, are not reciprocal. This view is not in harmony with either chemical, physical, or biological science of the present day, and stands in direct contradiction to the accepted doctrine of the correlation and conservation of energy.

Whatever may be the essential nature of the ultimate life-principle—with which science has nothing to do it can not be denied that life-phenomena are presented to us only through forms of matter. Matter, or material organization, is, therefore, so far as human knowledge goes, an absolute condition upon which all life-manifestations depend, and to assert, as do the "vitalists," that this vital energy an agency which can not be verified, though dependent upon a material condition for a display of its action is not related to it, but is independent of it and under distinct and antagonistic laws, is an assumption at variance with scientific truth and reason.

Doubtless one common source of error in the minds of the disciples of "vitalism" is inaccurate definition, confounding, as they do, the scientific meaning of a term with its philosophical or metaphysical significance. Thus, the term "life," when applied to the higher animals, is, to the metaphysical philosopher, often related to, or made synonymous with, the "soul"; while to the physiologist it refers only to the sum of phenomena arising in organized bodies. If what "can not be explained by chemistry or physics" constitutes the vital functions, then, by simply eliminating the known or non-vital factors, we may easily learn the exact amount of the vital element.