Like the Principles the tract opens with a protest against the empty abstractions, and consequent frivolous discussions, which even mechanical science had countenanced although dealing with matters so obvious to sense as the phenomena of motion. Force, effort, solicitation of gravity, nisus, are examples of abstract terms connected with motion, to which nothing in what is presented to the senses is found to correspond. Yet corporeal power is spoken of as if it were something perceptible by sense, and so found within the bodies we see and touch (sect. 1-3).
But it turns out differently when philosophers and naturalists try to imagine the physical force that is supposed to inhabit bodies, and to explain their motions. The conception of motion has been the parent of innumerable paradoxes and seeming contradictions among ancient Greek thinkers; for it presents, in a striking form, the [pg 492] metaphysical difficulties in the way of a reconciliation of the One and the Many—difficulties which Berkeley had already attributed to perverse abstractions, with which philosophers amused themselves and blocked up the way to concrete knowledge; first wantonly raising a dust, and then complaining that they could not see. Nor has modern mechanical science in this respect fared better than the old philosophies. Even its leaders, Torricelli, for instance, and Leibniz, offer us scholastic shadows—empty metaphysical abstractions—when they speak about an active power that is supposed to be lodged within the things of sense. Torricelli tells us that the forces within the things around us, and within our own bodies, are “subtle quintessences, enclosed in a corporeal substance as in the enchanted vase of Circe”; and Leibniz speaks of their active powers as their “substantial form,” whatever that can be conceived to mean. Others call the power to which change of place is due, the hylarchic principle, an appetite in bodies, a spontaneity inherent in them; or they assume that, besides their extension, solidity, and other qualities which appear in sense, there is also something named force, latent in them if not patent—in all which we have a flood of words, empty of concrete thought. At best the language is metaphorical (sect. 2-9).
For showing the active cause at work in the production of motion in bodies, it is of no avail to name, as if it were a datum of sense, what is not presentable to our senses. Let us, instead, turn to the only other sort of data in realised experience. For we find only two sorts of realities in experience, the one sort revealed by our senses, the other by inward consciousness. We can affirm nothing about the contents of bodies except what our senses present, namely, concrete things, extended, figured, solid, having also innumerable other qualities, which seem all to depend upon change of place in the things, or in their constituent particles. The contents [pg 493] of mind or spirit, on the other hand, are disclosed to inner consciousness, which reveals a sentient Ego that is actively percipient and exertive. And it must be in the second of these two concrete revelations of reality, that active causation, on which motion and all other change depends, is to be found—not in empty abstractions, covered by words like power, cause, force, or nisus, which correspond to nothing perceived by the senses (sect. 21).
So that which we call body presents within itself nothing in which change of place or state can originate causally. Extension, figure, solidity, and all the other perceptible constituents of bodies are appearances only—passive phenomena, which succeed one another in an orderly cosmical procession, on which doubtless our pains and pleasures largely depend. But there is no sensibly perceptible power found among those sensuous appearances. They can only be caused causes, adapted, as we presuppose, to signify to us what we may expect to follow that appearance. The reason of their significance, i.e. of the constancy of their sequences and coexistences, must be sought for outside of themselves. Experimental research may discover new terms among the correlated cosmical sequences or coexistences, but the newly discovered terms must still be only passive phenomena previously unperceived. Body means only what is presentable to the senses. Those who attribute to it something not perceptible by sense, which they call the force or power in which its motions originate, say in other words that the origin of motion is unknowable by sense (sect. 22-24).
Turn now from things of sense, the data of perception, to Mind or Spirit, as revealed in inner consciousness. Here we have a deeper and more real revelation of what underlies, or is presupposed in, the passive cosmical procession that is presented to the senses. Our inward consciousness plainly shews the thinking being actually [pg 494] exercising power to move its animated body. We find that we can, by a causal exertion of which we are distinctly conscious, either excite or arrest movements in bodies. In voluntary exertion we have thus a concrete example of force or power, producing and not merely followed by motion. In the case of human volition this is no doubt conditioned power; nevertheless it exemplifies Power on a greater scale than human, even Divine power, universally and continuously operative, in all natural motions, and in the cosmical laws according to which they proceed (sect. 25-30).
Thus those who pretend to find force or active causation within bodies, pretend to find what their sensuous experience does not support, and they have to sustain their pretence by unintelligible language. On the other hand, those who explain motion by referring it to conscious exertion of personal agents, say what is supported by their own consciousness, and confirmed by high authorities, including Anaxagoras, Plato, Aristotle, Descartes, and Newton, demonstrating that in Spirit only do we find power to change its own state, as well as the states and mutual relations of bodies. Motion in nature is God continuously acting (sect. 31-34). But physical science is conveniently confined to the order of the passive procession of sensuous appearances, including experiments in quest of the rules naturally exemplified in the motions of bodies: reasoning on mathematical and mechanical principles, it leaves the contemplation of active causation to a more exalted science (sect. 35-42).
In all this it can hardly be said that Berkeley has in this adequately sounded the depths of Causation. He proclaims inability to find through his senses more than sequence of significant sensuous appearances, which are each and all empty of active power; while he apparently insists that he has found active power in the mere feeling [pg 495]of exertion; which after all, as such, is only one sort of antecedent sign of the motion that is found to follow it. This is still only sequence of phenomena; not active power. But is not causation a relation that cannot be truly presented empirically, either in outer or inner consciousness? And is not the Divine order that is presupposed by us in all change, a presupposition that is inevitable in trustworthy intercourse with a changing universe; unless we are to confess atheistically, that our whole sensuous experience may in the end put us to utter confusion? The passive, uneasy feeling of strain, more or less involved in the effort to move our bodies and their surroundings, is no doubt apt to be confused with active causation; for as David Hume remarks, “the animal nisus which we experience, though it can afford no accurate precise idea of power, enters very much into the vulgar, inaccurate idea which is formed of it.” So when Berkeley supposes that he has found a concrete example of originating power in the nisus of which we are conscious when we move our bodies, he is surely too easily satisfied. The nisus followed by motion is, per se, only a natural sequence, a caused cause, which calls for an originating cause that is absolutely responsible for the movement. Is not the index to this absolutely responsible agency an ethical one, which points to a free moral agent as alone necessarily connected with, or responsible for, the changes which he can control? Persons are causally responsible for their own actions; and are accordingly pronounced good or evil on account of acts of will that are not mere caused causes—passively dependent terms in the endless succession of cosmical change. They must originate in self, be absolutely self-referable, in a word supernatural issues of the personality. Moral reason implies that they are not determined ab extra, and so points to moral agents as our only concrete examples of independent power; but this only so far as those issues go for which they are morally [pg 496] responsible. Is not faith in the Universal Power necessarily faith-venture in the absolutely perfect and trustworthy moral agency of God?