100. Objective Validity of the Traditional Concept of Efficient Causality.—We have seen how modern sensists, phenomenists, and positivists have doubted or denied the power of the human mind to attain to a knowledge of any objective reality corresponding to the category of substance (§§ [61] sqq.). They treat in a similar way the traditional concept of efficient causality. And in delivering their open or veiled attacks on the real validity of this notion they have made a misleading use of the proper and legitimate function of the inductive sciences. The chief aim of the natural scientist is to seek out and bring to light the whole group of necessitating and indispensable (phenomenal) antecedents of any given kind of event, and to formulate the natural law of their connexion with this kind of event. There is no particular objection to his calling these antecedents the invariable, or even the necessary or necessitating, antecedents of the event; provided he does not claim what he cannot prove—and what, as we shall see later ([104]), is not true, viz.—that the invariability or necessity of this connexion between phenomenal antecedents and consequents is wholly inviolable, fatal, absolute in character. He may rightly claim for any such established connexion the hypothetical, conditional necessity which characterizes all inductively established laws of physical nature. There are such antecedents and consequents in the universe; there are connexions between them which are more than mere casual connexions of time sequence, which are connexions of physical law, inasmuch as they are connexions based on the natures of agencies in an orderly universe, connexions of these agencies with their natural effects. All this is undeniable. Moreover, so long as the scientist confines himself to inferences concerning such connexions between phenomena, to inferences and generalizations based on the assumed uniformity of nature, he is working in his proper sphere. Nay, even if he chooses to [pg 382] designate these groups of invariable phenomenal antecedents by the title of “physical causes” we know what he means; though we perceive some danger of confusion, inasmuch as we see him arrogating to the notion of regularity or uniformity of connexion i.e. to the notion of physical law, a term, causality, which traditionally expressed something quite distinct from this, viz. the notion of positive influence of one thing on the being or happening of another. But when phenomenist philosophers adopt this usage we cannot feel reassured against the danger of confusion by such protestations as those of Mill in the following passage:—[469]
I premise, then, that when in the course of this inquiry I speak of the cause of any phenomenon, I do not mean a cause which is not itself a phenomenon; I make no research into the ultimate or ontological cause of anything. To adopt a distinction familiar in the writings of the Scotch metaphysicians, and especially of Reid, the causes with which I concern myself are not efficient, but physical causes. They are causes in that sense alone, in which one physical fact is said to be the cause of another. Of the efficient causes of phenomena, or whether any such causes exist at all I am not called upon to give an opinion. The notion of causation is deemed, by the schools of metaphysics most in vogue at the present moment, to imply a mysterious and most powerful tie, such as cannot, or at least does not, exist between any physical fact and that other physical fact on which it is invariably consequent, and which is popularly termed its cause; and thence is deduced the supposed necessity of ascending higher, into the essences and inherent constitution of things, to find the true cause, the cause which is not only followed by, but actually produces, the effect. No such necessity exists for the purposes of the present inquiry, nor will any such doctrine be found in the following pages. The only notion of a cause, which the theory of induction requires, is such a notion as can be gained by experience. The Law of Causation, which is the main pillar of inductive science, is but the familiar truth, that invariability of succession is found by observation to obtain between every fact in nature and some other fact which has preceded it; independently of all considerations respecting the ultimate mode of production of phenomena, and of every other question regarding the nature of “Things in themselves”.
This passage—which expresses fairly well the phenomenist and positivist attitude in regard to the reality, or at least the cognoscibility, of efficient causes—fairly bristles with inaccuracies, misconceptions, and false insinuations.[470] But we are concerned here [pg 383] only with the denial that any notion of an efficient cause “can be gained from experience,” and the doubt consequently cast on the objective validity of this notion. The Sensism which regards our highest intellectual activities as mere organic associations of sentient states of consciousness, has for its logical issue the Positivism which contends that all valid knowledge is confined to the existence and time and space relations of sense phenomena. In thus denying to the mind all power of attaining to a valid knowledge of anything suprasensible—such as substance, power, force, efficient cause, etc.—Positivism passes over into Agnosticism.
In refutation of this philosophy, in so far as it denies that we have any grounds in experience for believing in the real existence of efficient causes, we may set down in the first place this universal belief itself of the human race that there are in the universe efficient causes of the events that happen in it. Men universally believe that they themselves as agents contribute by a real and positive influence to the actual occurrence of their own thoughts, reasonings, wishes, desires, sensations; that their mental resolves to speak, walk, write, eat, or perform any other external, bodily [pg 384] works do really, positively, and efficiently produce or cause those works; that external phenomena have a real influence on happenings in their own bodies, that fire burns them and food nourishes them; that external phenomena also have a real and positive influence on their sense organs, and through these on their minds by the production there of conscious states such as sensations; finally that external phenomena have a real and positive influence on one another; that by action and interaction they really produce the changes that are constantly taking place in the universe: that the sun does really heat and light the earth, that the sowing of the seed in springtime has really a positive influence on the existence of crops in the harvest, that the taking of poison has undoubtedly a real influence on the death which results from it. And if any man of ordinary intelligence and plain common sense is told that such belief is an illusion, that in all such cases the connexion between the things, facts or events which he designates as “cause” and “effect,” is a mere connexion of invariable time sequence between antecedents and consequents, that in no case is there evidence of any positive, productive influence of the one fact upon the other, he will either smile incredulously and decline to take his objector seriously, or he will simply ask the latter to prove the universal belief to be an illusion. His conviction of the real and objective validity of his notion of efficient cause, as something which positively influences the happening of things, is so profound and ineradicable that it must necessarily be grounded in, and confirmed by, his constant experience of the real world in which he lives and moves. Not that he professes to be able to explain the nature of this efficient influence in which he believes. Even if he were a philosopher he might not be able to satisfy himself or others on this point But being a plain man of ordinary intelligence he has sense enough to distinguish between the existence of a fact and its nature, its explanation, its quomodo; and to believe in the real existence of a positive efficient, productive influence of cause on effect, however this influence is to be conceived or explained.
A second argument for the objective validity of the concept of efficient cause may be drawn from a consideration of the Principle of Causality. The experience on which the plain man grounds his belief in the validity of his notion of cause is not mere uninterpreted sense experience in its raw and brute condition, so to speak; it is this sense experience rationalized, assimilated into [pg 385] his intelligence—spontaneously and half unconsciously, perhaps—by the light of the self-evident Principle of Causality, that whatever happens has a cause. When the plain man believes that all the various agencies in nature, like those enumerated above, are not merely temporal antecedents or concomitants of their effects, but are really productive of those effects, he is really applying the universal and necessary truth—that an “event,” a “happening,” a “change,” a “commencement” of any new actual mode of being demands the existence of another actual being as cause—the truth embodied in the Principle of Causality, to this, that, and the other event of his experience: he is locating the “causes” of these events in the various persons and things which he regards as the agents or producers of these events. In making such applications he may very possibly err in detail. But no actual application of the principle at all is really required for establishing the objective validity of the concept of cause. There are philosophers who—erroneously, as we shall see—deny that the Principle of Causality finds its application in the domain of created things, who hold, in other words, that no created beings can be efficient causes (102), and who nevertheless recognize, and quite rightly, that the concept of efficient cause is an objectively valid concept. And they do so because they see that since events, beginnings, happenings, changes, are real, there must be really and objectively existent an efficient cause of them—whatever and wherever such efficient cause may be: whether it be one or manifold, finite or infinite, etc.
We have already examined Hume's attempt to deny the ontological necessity of the Principle of Causality and to substitute therefor a subjectively or psychologically necessary “feeling of expectation” grounded on habitual association of ideas. Kant, on the other hand, admits the self-evident, necessary character of the Principle; but holds that, since this necessity is engendered by the mind's imposing a subjective form of thought on the data of sense consciousness, the principle is validly applicable only to connexions within the world of mental appearances, and not at all to the world of real being. He thus transfers the discussion to the domain of Epistemology, where in opposition to his theory of knowledge the Principle of Causality can be shown to be applicable to all contingent reality, and to be therefore legitimately employed in Natural Theology for the purpose of establishing the real existence of an Uncaused First Cause.
101. Origin of the Concept of Efficient Cause.—We have seen that universal belief in the real existence of efficient causes is grounded in experience. The formation of the concept, [pg 386] and its application or extension to the world within and around us, are gradual.[471] Active power, force, energy, efficiency, faculty, or by whatever other name we may call it, is of course experienced only in its actual exercise, in action, motion, production of change. Our first experience of its exercise is found in our consciousness of our own personal activities, mental and bodily: in our thinking, willing or choosing, in our deliberate control of our mental processes, and in the deliberate exercise of our sense faculties and bodily organs. In all this we are conscious of exerting power, force, energy: we apprehend ourselves as agents or efficient causes of our mental processes and bodily movements. We apprehend these happenings as due to the exercise of our own power to produce them. Seeing other human beings behave like ourselves, we infer by analogy that they also possess and exercise active powers like our own, that they, too, are efficient causes. Finally, observing that effects like to those produced by ourselves, whether in ourselves or in the material world around us, are also consequent on certain other changes in external nature, whether organic or inorganic, we infer by analogy that these corporeal things have also powers, forces, energies, whereby they produce these effects. While our senses testify only to time and space connexions between physical happenings in external nature, our intellect apprehends action and interaction, i.e. causal dependence of events on the active influence or efficiency of physical things as agents or causes.[472] Thus, our knowledge of the existence and nature of the forces, powers and energies which constitute material things efficient causes is posterior to, and derived by analogy from, our knowledge of the mental and bodily powers which reveal themselves to us in our conscious vital processes as constituting our own personal efficient causality.
This conception of efficient causality even in the inanimate things of external nature, after the analogy of our own vital powers as revealed in our conscious activities, is sometimes disparaged as naïve anthropomorphism. It just depends on the manner [pg 387] and degree in which we press the analogy. Observing that our earlier notion of cause is “the notion of power combined with a purpose and an end” (thus including efficient and final causality), Newman remarks[473] that “Accordingly, wherever the world is young, the movements and changes of physical nature have been and are spontaneously ascribed by its people to the presence and will of hidden agents, who haunt every part of it, the woods, the mountains and the streams, the air and the stars, for good or for evil—just as children again, by beating the ground after falling, imply that what has bruised them has intelligence”. This is anthropomorphism. So, too, would be the conception of the forces or powers of inanimate nature as powers of sub-conscious “perception” and “appetition” (Leibniz), or, again, as rudimentary or diminished “will-power” (Cousin).[474] “Physical phenomena, as such, are without sense,” as Newman rightly observes; and consequently we may not attribute to them any sort of conscious efficiency, whether perceptive or appetitive. But Newman appears to err in the opposite direction when he adds that “experience teaches us nothing about physical phenomena as causes”.[475] The truth lies between these extremes. Taking experience in the wide sense in which it includes rational interpretation of, and inference from, the data of internal and external sense perception, experience certainly reveals to us the existence of physical phenomena as efficient causes, or in other words that there is real and efficient causality not only in our own persons but also in the external physical universe; and as to the nature of this causality it also gives us at least some little reliable information.
By pursuing this latter question a little we shall be led to examine certain difficulties which lie at the root of Occasionalism: the error of denying that creatures, or at least merely corporeal [pg 388] creatures, can be in any true sense efficient causes. A detailed inquiry into the nature of the active powers, forces or energies of the inorganic universe, i.e. into the nature of corporeal efficient causality, belongs to Cosmology; just as a similar inquiry into vital, sentient and spiritual efficient causality belongs to Psychology. Here we have only to ascertain what is common and essential to all efficient causality as such, what in general is involved in the exercise of efficient causality, in actio and passio, and what are the main implications revealed in a study of it.
102. Analysis of Efficient Causality, or Actio and Passio: (a) The First Cause and Created Causes.—We have already referred to the universal dependence of all created causes on the First Cause; and we shall have occasion to return to it in connexion with Occasionalism. God has created all second causes; He has given them their powers of action; He conserves their being and their powers in existence; He applies these powers or puts them in act; He concurs with all their actions; He is therefore the principal cause of all their effects; and in relation to Him they are as instrumental causes: “Deus est causa actionis cujuslibet inquantum dat virtutem agendi, et inquantum conservat eam, et inquantum applicat actioni, et inquantum ejus virtute omnis alia virtus agit.”[476]