The Approach to Philosophy

by Ralph Barton Perry

§ [111]. The origin of the present known natural world was the first philosophical question to be definitely met by science. The general form of solution which naturalism offers is anticipated in the most ancient theories of nature. These already suppose that the observed mechanical processes of the circular or periodic type, like the revolutions and rotations of the stars, are incidents in a historical mechanical process of a larger scale. Prior to the present fixed motions of the celestial bodies, the whole mass of cosmic matter participated in irregular motions analogous to present terrestrial redistributions. Such motions may be understood to have resulted in the integration of separate bodies, to which they at the same time imparted a rotary motion. It is such a hypothesis that Lucretius paints in his bold, impressionistic colors.

But the development of mechanics paved the way for a definite scientific theory, the so-called "nebular hypothesis," announced by La Place in 1796, and by the philosopher Kant at a still earlier date. Largely through the Newtonian principle of the parallelogram of forces, the present masses, orbits, and velocities were analyzed into a more primitive process of concentration within a nebulous or highly diffused aggregate of matter. And with the aid of the principle of the conservation of energy this theory appears to make possible the derivation of heat, light, and other apparently non-mechanical processes from the same original energy of motion.

But a persistently philosophical mind at once raises the question of the origin of this primeval nebula itself, with a definite organization and a vast potential energy that must, after all, be regarded as a part of nature rather than its source. Several courses are here open to naturalism. It may maintain that the question of ultimate origin is unanswerable; it may regard such a process of concentration as extending back through an infinitely long past;[243:12] or, and this is the favorite alternative for more constructive minds, the historical cosmical process may be included within a still higher type of periodic process, which is regarded as eternal. This last course has been followed in the well-known synthetic naturalism of Herbert Spencer. "Evolution," he says, "is the progressive integration of matter and dissipation of motion." But such a process eventually runs down, and may be conceived as giving place to a counter-process of devolution which scatters the parts of matter and gathers another store of potential motion. The two processes in alternation will then constitute a cosmical system without beginning or end.

In such wise a sweeping survey of the physical universe may be thought in the terms of natural science. The uniformitarian method in geology, resolving the history of the crust of the earth into known processes, such as erosion and igneous fusion;[244:13] and spectral analysis, with its discoveries concerning the chemical constituents of distant bodies through the study of their light, have powerfully reënforced this effort of thought, and apparently completed an outline sketch of the universe in terms of infra-organic processes.

Life. Natural Selection.

§ [112]. But the cosmos must be made internally homogeneous in these same terms. There awaits solution, in the first place, the serious problem of the genesis and maintenance of life within a nature that is originally and ultimately inorganic. The assimilation of the field of biology and physiology to the mechanical cosmos had made little real progress prior to the nineteenth century. Mechanical theories had, indeed, been projected in the earliest age of philosophy, and proposed anew in the seventeenth century.[245:14] Nevertheless, the structural and functional teleology of the organism remained as apparently irrefutable testimony to the inworking of some principle other than that of mechanical necessity. Indeed, the only fruitful method applicable to organic phenomena was that which explained them in terms of purposive adaptation. And it was its provision for a mechanical interpretation of this very principle that gave to the Darwinian law of natural selection, promulgated in 1859 in the "Origin of Species," so profound a significance for naturalism. It threatened to reduce the last stronghold of teleology, and completely to dispense with the intelligent Author of nature.

Darwin's hypothesis sought to explain the origin of animal species by survival under competitive conditions of existence through the possession of a structure suited to the environment. Only the most elementary organism need be presupposed, together with slight variations in the course of subsequent generations, and both may be conceived to arise mechanically. There will then result in surviving organisms a gradual accumulation of such variations as promote survival under the special conditions of the environment. Such a principle had been suggested as early as the time of Empedocles, but it remained for Darwin to establish it with an unanswerable array of observation and experimentation. If any organism whatsoever endowed with the power of generation be allowed to have somehow come to be, naturalism now promises to account for the whole subsequent history of organic phenomena and the origin of any known species.

Mechanical Physiology.

§ [113]. But what of life itself? The question of the derivation of organic from inorganic matter has proved insoluble by direct means, and the case of naturalism must here rest upon such facts as the chemical homogeneity of these two kinds of matter, and the conformity of physiological processes to more general physical laws. Organic matter differs from inorganic only through the presence of proteid, a peculiar product of known elements, which cannot be artificially produced, but which is by natural means perpetually dissolved into these elements without any discoverable residuum. Respiration may be studied as a case of aerodynamics, the circulation of the blood as a case of hydrodynamics, and the heat given off in the course of work done by the body as a case of thermodynamics. And although vitalistic theories still retain a place in physiology, as do teleological theories in biology, on the whole the naturalistic programme of a reduction of organic processes to the type of the inorganic tends to prevail.

Mind. The Reduction to Sensation.