The Approach to Philosophy

by Ralph Barton Perry

"When a Frenchman arrives in London, he finds a very great change, in philosophy as well as in most other things. In Paris he left the world all full of matter; here he finds absolute vacua. At Paris the universe is seen filled up with ethereal vortices, while here the same space is occupied with the play of the invisible forces of gravitation. In Paris the earth is painted for us longish like an egg, and in London it is oblate like a melon. At Paris the pressure of the moon causes the ebb and flow of tides; in England, on the other hand, the sea gravitates toward the moon, so that at the same time when the Parisians demand high water of the moon, the gentlemen of London require an ebb."[232:6]

But these differences are not matters of taste, nor even rival hypotheses upon an equal footing. The Newtonian system of mechanics, the consummation of a development initiated by Galileo, differed from the vortex theory of Descartes as exact science differs from speculation and unverified conjecture. And this difference of method carried with it eventually certain profound differences of content, distinguishing the Newtonian theory even from that of Democritus, with which it had so much in common. Although Democritus had sought to avoid the element of purposiveness in the older hylozoism by referring the motions of bodies as far as possible to the impact of other bodies, he nevertheless attributed these motions ultimately to weight, signifying thereby a certain downward disposition. Now it is true that in his general belief Newton himself is not free from hylozoism. He thought of the motions of the planets themselves as initiated and quickened by a power emanating ultimately from God. They are "impressed by an intelligent Agent," and

"can be the effect of nothing else than the wisdom and skill of a powerful ever-living Agent who, being in all places, is more able by his will to move the bodies within his boundless uniform sensorium, and thereby to form and reform the parts of the universe, than we are by our will to move the parts of our own bodies."[233:7]

But by the side of these statements must be set his famous disclaimer, "hypotheses non fingo." In his capacity of natural philosopher he did not seek to explain motions, but only to describe them. Disbelieving as he did in action at a distance, he saw no possibility of explanation short of a reference of them to God; but such "hypotheses" he thought to be no proper concern of science. As a consequence, the mathematical formulation of motions came, through him, to be regarded as the entire content of mechanics. The notion of an efficient cause of motion is still suggested by the term force, but even this term within the system of mechanics refers always to a definite amount of motion, or measurement of relative motion. And the same is true of attraction, action, reaction, and the like. The further explanation of motion, the definition of a virtue or potency that produces it, first a neglected problem, then an irrelevant problem, is finally, for a naturalistic philosophy in which this progression is completed, an insoluble problem. For the sequel to this purely descriptive procedure on the part of science is the disavowal of "metaphysics" by those who will have no philosophy but science. Thus the scientific conservatism of Newton has led to the positivistic and agnostic phase of naturalism. But a further treatment of this development must be reserved until the issue of epistemology shall have been definitely raised.

A different emphasis within the general mechanical scheme, attaching especial importance to the conceptions of force and energy, has led to a rival tendency in science and a contrasting type of naturalism. The mechanical hypotheses hitherto described are all of a simple and readily depicted type. They suggest an imagery quite in accord with common-sense and with observation of the motions of great masses like the planets. Material particles are conceived to move within a containing space; the motions of corpuscles, atoms, or the minute parts of ether, differing only in degree from those of visible bodies. The whole physical universe may be represented in the imagination as an aggregate of bodies participating in motions of extraordinary complexity, but of one type. But now let the emphasis be placed upon the determining causes rather than upon the moving bodies themselves. In other words, let the bodies be regarded as attributive and the forces as substantive. The result is a radical alteration of the mechanical scheme and the transcendence of common-sense imagery. This was one direction of outgrowth from the work of Newton. His force of gravitation prevailed between bodies separated by spaces of great magnitude. Certain of the followers of Newton, notably Cotes, accepting the formulas of the master but neglecting his allusions to the agency of God, accepted the principle of action at a distance. Force, in short, was conceived to pervade space of itself. But if force be granted this substantial and self-dependent character, what further need is there of matter as a separate form of entity? For does not the presence of matter consist essentially in resistance, itself a case of force? Such reflections as these led Boscovich and others to the radical departure of defining material particles as centres of force.

The Development and Extension of the Conception of Energy.

§ [108]. But a more fruitful hypothesis of the same general order is due to the attention directed to the conception of energy, or capacity for work, by experimental discoveries of the possibility of reciprocal transformations without loss, of motion, heat, electricity, and other processes. The principle of the conservation of energy affirms the quantitative constancy of that which is so transformed, measured, for example, in terms of capacity to move units of mass against gravity. The exponents of what is called "energetics" have in many cases come to regard that the quantity of which is so conserved, as a substantial reality whose forms and distributions compose nature. A contemporary scientist, whose synthetic and dogmatic habit of mind has made him eminent in the ranks of popular philosophy, writes as follows:

"Mechanical and chemical energy, sound and heat, light and electricity, are mutually convertible; they seem to be but different modes of one and the same fundamental force or energy. Thence follows the important thesis of the unity of all natural forces, or, as it may also be expressed, the 'monism of energy.'"[236:8]

The conception of energy seems, indeed, to afford an exceptional opportunity to naturalism. We have seen that the matter-motion theory was satisfied to ignore, or regard as insoluble, problems concerning the ultimate causes of things. Furthermore, as we shall presently see to better advantage, the more strictly materialistic type of naturalism must regard thought as an anomaly, and has no little difficulty with life. But the conception of energy is more adaptable, and hence better qualified to serve as a common denominator for various aspects of experience. The very readiness with which we can picture the corpuscular scheme is a source of embarrassment to the seeker after unity. That which is so distinct is bristling with incompatibilities. The most aggressive materialist hesitates to describe thought as a motion of bodies in space. Energy, on the other hand, exacts little if anything beyond the character of measurable power. Thought is at any rate in some sense a power, and to some degree measurable. Recent discoveries of the dependence of capacity for mental exertion upon physical vitality and measurements of chemical energy received into the system as food, and somehow exhausted by the activities of thought, have lent plausibility to the hypothesis of a universal energy of which physical and "psychical" processes are alike manifestations. And the conception of energy seems capable not only of unifying nature, but also of satisfying the metaphysical demand for an efficient and moving cause. This term, like "force" and "power," is endowed with such a significance by common sense. Indeed, naturalism would seem here to have swung round toward its hylozoistic starting-point. The exponent of energetics, like the naive animistic thinker, attributes to nature a power like that which he feels welling up within himself. When he acts upon the environment, like meets like. Energetics, it is true, may obtain a definite meaning for its central conception from the measurable behavior of external bodies, and a meaning that may be quite free from vitalism or teleology. But in his extension of the conception the author of a philosophical energetics abandons this strict meaning, and blends his thought even with a phase of subjectivism, known as panpsychism.[238:9] This theory regards the inward life of all nature as homogeneous with an immediately felt activity or appetency, as energetics finds the inner life to be homogeneous with the forces of nature. Both owe their philosophical appeal to their apparent success in unifying the world upon a direct empirical basis, and to their provision for the practical sense of reality.