Understanding by natural law the natural inclination or tendency of the creature to a definite line of activity, this law is of itself determining or necessitating. Moreover, it is absolutely inseparable from the essence of the creature. Granted that the creature exists, it has this tendency to exert and direct all its forces and energies in a definite, normal way, for the realization of its end. This nisus naturae is never absent; it is observable even where, as in the generation of “monsters” by living organisms, it partially fails to attain its end. A law of nature, taken in this sense, is absolutely necessary to, and inseparable from, the created agent; it admits of no exceptions; no agent can exist without it; for it is identical with the very being of the agent
But the uniformity of action resulting from this natural tendency, the uniform series of normal operations whereby it realizes its end, is not absolutely necessary, inviolable, unexceptional. In the first place the Author of Nature can, for a higher or moral purpose, prevent any created agency supernaturally, miraculously, from actually exercising its active powers in accordance with its nature for the prosecution of its natural end. But apart altogether from this, abstracting from all special interference of the First Cause, and confining our attention to the natural order itself, we have to consider that for any physical agency to act in its natural or normal manner certain extrinsic conditions are always requisite: oxygen and hydrogen, for instance, [pg 422] will combine to produce water, but only under certain conditions of contact, pressure, temperature, etc. This general requirement arises from the fact already mentioned, that physical agencies co-exist in time and space and are constantly interacting. These extrinsic conditions are, of course, not expressly stated in the formulation of those uniformities and quantitative descriptions called “laws of nature” in the second and third interpretations of this expression as explained above. It is taken as understood that the law applies only if and when and where all such conditions are verified. The law, therefore, as stated categorically, does not express an absolutely necessary, universal, and unexceptional truth. It may admit of exceptions.
In the next place, when we come to examine these exceptions to uniformity, these failures or frustrations of the normal or natural activities of physical agencies, we find it possible to distinguish roughly, with Aristotle, between two groups of such “uniformities” or “laws”. There are firstly those which, so far as our experience goes, seem to prevail always (ἀεὶ), unexceptionally; and secondly, those which seem to prevail generally, for the most part (ἐπὶ τὸ πολὺ), though not unexceptionally. The former would be the outcome of active powers, energies, forces, de facto present and prevalent always and everywhere in all physical agencies, and of such a character that the conditions requisite for their actual operation would be always verified. Such, for instance, would be the force of gravity in all ponderable matter; and hence the law of gravitation is regarded as all-pervading, universal, unexceptional. But there are other natural or normal effects which are the outcome of powers, forces, energies, not all-pervading, but restricted to special groups of agencies, dependent for their actual production on the presence of a great and complex variety of extrinsic conditions, and liable therefore to be impeded by the interfering action of numerous other natural agencies. Such, for instance, would be the natural powers and processes whereby living organisms propagate their kind. The law, therefore, which states it to be a uniformity of nature that living organisms reproduce offspring similar to themselves in kind, is a general law, admitting exceptions.
Operations and effects which follow from the nature of their causes are called natural (καθ᾽ ἁυτό, καὶ μὴ κατὰ συμβεβηκός).[515] Some causes produce their natural effects always (τὰ ἐξ ἀνάνκης [pg 423] καὶ ἀεὶ γιγνομένα), others produce their natural effects usually, as a general rule (τὰ ὡς ἐπι πολὺ γιγνόμενα).[516] Operations and effects which are produced by the interfering influence of extrinsic agencies (τὸ βίαιον “violent,” as opposed to natural), and not in accordance with the nature of their principal cause, are called by Aristotle accidental (τὰ κατὰ συμβεβηκός, τὰ ἐνδεχόμενα γυγνέσθαι); and these, he remarks, people commonly describe as due to chance (καὶ ταῦτα πάντες φασὶν εἰναι ἀπο τύχης).[517]
All are familiar with events or happenings described as “fortuitous,” “accidental,” “exceptional,” “unexpected,” with things happening by “chance,” by (good or bad) “luck” or “fortune”.[518] There are terms in all languages expressive of this experience—casus, sors, fortuna, τύχη, etc. The notion underlying all of them is that of something occurring unintentionally, praeter intentionem agentis. Whether chance effects result from the action of intelligent agents or from the operation of physical causes they are not “intended,”—by the deliberate purpose of the intelligent agent in the one case, or by the natural tendency, the intentio naturae, of the mere physical agency in the other. Such an effect, therefore, has not a natural cause; hence it is considered exceptional, and is always more or less unexpected. Nature, as Aristotle rightly observes,[519] never produces a chance effect. His meaning is, that whenever such an effect occurs it is not brought about in accordance with the natural tendency of any physical agency. It results from a collision or coincidence of two or more such agencies, each acting according to its nature. The hunter's act of firing at a wild fowl is an intentional act. The boy's act of coming into the thicket to gather wild flowers is an intentional act. The accidental shooting of the boy is the result of a coincidence of the two intentional acts. Similarly, each of all the various agencies which bring about the development of an embryo in the maternal womb has its own immediate and particular natural effect, and only mediately contributes to the general effect of bringing the embryo to maturity. As a rule these particular effects are favourable to the general effect. But sometimes the immediate ends do not subserve this ulterior purpose. The result is accidental, exceptional, a deviation from the normal type, an anomaly, a “monster” in the domain of living organisms.
Aristotle's analysis, correct so far, is incomplete. It assigns no ultimate explanation of the fact that there are such encounters of individual natural tendencies in the universe, such failures in the subordination of particular ends to wider ulterior ends. As a matter of fact these chance effects, although not “intended” by the natures of individual created agencies, are not wholly and entirely unintended. They are not wholly aimless. They enter into the general plan and scheme of things as known and willed by the Author of Nature. They are known to His Intelligence, and willed and ruled by His Providence. For Him there can be no such thing as chance. Effects that are accidental in relation to created causes, effects that run counter to the nature or intentio naturae of these, are foreseen and willed by Him and made to subserve that wider and more general end which is the universal order of the world that He has actually willed to create. It is only in relation to the natures of individual agencies, and to the limited horizon of our finite intelligences, that such phenomena can present the aspect of fortuitous or chance occurrences.
Before passing on to deal, in our concluding section, with the great fact of order, let us briefly compare with the foregoing explanation of nature and its laws the attempt of mechanists to explain these without recognizing in the physical universe any influence of final causes, or any indication of a purposive intelligence. We have ventured to describe their attitude as philosophic fatalism.[520] According to their view there is no ground for the distinction between phenomena that happen “naturally” and phenomena that happen “accidentally” or “by chance”. All alike happen by the same kind of general necessity: the generation of a “monster” is as “natural” as the generation of normal offspring; the former, when it occurs, is just as inevitably the outcome of the physical forces at work in the particular case as the latter is the outcome of the particular set of efficient causes which do actually produce the normal result: the only difference is that [pg 425] the former, occurring less frequently and as the result of a rarer and less known conjunction of “physical” causes than the latter, is not expected by us to occur, and is consequently regarded, when it does occur, as exceptional. Now it is quite true that what we call “chance” effects, or “exceptional” effects, result just as inevitably from the set of forces operative in their case, as normal effects result from the forces operative in theirs. But this leaves for explanation something which the mechanist cannot explain. He regards a physical law merely as a generalization, beyond experience, of some experienced uniformity; and he holds that all our physical laws are provisional in the sense that a wider and deeper knowledge of the actual conditions of interaction among the physical forces of the universe would enable us to eliminate exceptions—which are all apparent, not real—by restating our laws in such a comprehensive way as to include all such cases. We may, indeed, admit that our physical laws are open to revision and restatement in this sense, and are de facto often modified in this sense by the progress of science. But the important point is this, that the mechanist does not admit the existence, in physical agencies, of any law in the sense of a natural inclination towards an end, or in any sense in which it would imply intelligence, design, or purpose. On the contrary, claiming as he does that all physical phenomena are reducible to mechanical motions of inert masses, atoms, or particles of matter in space, he is obliged to regard all physical agencies as being, so far as their nature is concerned, wholly indifferent to any particular form of activity.[521] Committed to the indefensible view that all qualitative change is reducible to quantitative ([11]), and all material differences to differences in the location of material particles and in the velocity and direction of the spatial motion impressed upon each by others extrinsic to itself, he has left himself no factors wherewith to explain the actual order and course of the universe, other than the purely indifferent factors of essentially or naturally homogeneous particles of inert matter endowed with local motion. We emphasize this feature of indifference; for the conception of an inert particle of matter subject to mechanical motion impressed upon it from without, is the very type of an indifferent agency. What such an entity will do, whether or not it will move, with what velocity and in what direction it will move—in a word, its entire conduct, its rôle in the universe, the sum-total of its functions—nothing of all this is dependent [pg 426] on itself; everything depends on agencies extrinsic to it, and on its extrinsic time-and-space relations to these agencies; and these latter in turn are in the same condition as itself. Now is it conceivable that agencies of this kind, of themselves absolutely indifferent to any particular kind of effect, suitable or unsuitable, regular or irregular, orderly or disorderly, could actually produce and maintain the existing order of the universe? If they were themselves produced by an All-Wise and All-Powerful Being, and definitely arranged in spatial relations to one another, and initial mechanical motion in definite directions and velocities impressed on the different parts of the system, there is no denying that Infinite Wisdom and Power could, by Divine concurrence even with such indifferent agencies, realize and maintain a cosmos, or orderly universe. Such purely extrinsic finality ([106]) could, absolutely speaking, account for the existence of order, uniformity, regularity, system; though all the evidence furnished by the universe of our actual experience points to the existence of intrinsic finality also as understood by Aristotle and the scholastics. But the mechanist will not allow even extrinsic finality; he will not recognize in the actual universe of our experience any evidence of a Ruling Intelligence realizing a plan or design for an intelligent purpose; he denies the necessity of the inference from the data of human experience to the existence of a Guiding Intelligence. And what are his alternatives? He may choose one or other of two.
He may restate in the more scientific and imposing terminology of modern mechanics the crude conception of the ancient Greek atomists: that the actual order of the universe is the absolutely inevitable and fatal outcome of a certain collocation of the moving masses of the physical universe, a collocation favourable to order, a collocation which just happened to occur by some happy chance from the essentially aimless, purposeless, indifferent and chaotic motions of those material masses and particles. We say “chaotic,” for chaos is the absence of cosmos; and order is the fact that has got to be explained. In the concept of indifferent, inert atoms of matter moving through space there is emphatically no principle of order;[522] and hence the mechanist who will not admit the necessity of inferring an Intelligence to give these moving masses or atoms the collocation favourable to order is forced to “explain” [pg 427] this supposed collocation by attributing it to pure chance—the concursus fortuitus atomorum of the ancient Greeks. When, however, we reflect that the more numerous these atoms and the more varied and complex their motions, the smaller is the chance of a collocation favourable to order; that the atoms and motions are supposed actually to surpass any assignable number; that therefore the chance of any such favourable collocation occurring is indefinitely smaller than any measurable proportion,—we can draw our own conclusions about the value of such a speculation as a rational “explanation” of the existing cosmos. And this apart altogether from the consideration that the fact to be explained is not merely the momentary occurrence of an orderly collocation, but the maintenance of an orderly system of cosmic phenomena throughout the lapse of all time. No orderly finite system of mechanical motions arranged by human skill can preserve its orderly motions indefinitely without intelligent human supervision: the neglected machine will get out of order, run down, wear out, if left to itself; and we are asked to believe that the whole universe is one vast machine which not only goes on without intelligent supervision, but which actually made itself by chance![523]
Naturally such an “explanation” of the universe does not commend itself to any man of serious thought, whatever his difficulties may be against the argument from the fact of order in the universe to the existence of an Intelligent Designer. Add to this the consideration that the mechanist theory does not even claim to account for the first origin of the universe: it postulates the existence of matter in motion. In regard to this supreme problem of the first origin of the universe the attitude of the mechanist is avowedly agnostic; and in view of what we have just remarked about the “chance” theory as an “explanation” of the existing order of the universe, it is no matter for surprise that most mechanists reject this theory and embrace the agnostic attitude in regard to this latter problem also. Whether the agnostic attitude they assume be negative or positive, i.e. whether they are content to say that they themselves at least fail to find any satisfactory rational explanation of the origin and nature of the cosmos, or contend further that no rational solution of these problems is within the reach of the human mind, their [pg 428] teaching is refuted in Natural Theology, where the theistic solution of these problems is set forth and vindicated.
110. The Order of the Universe; A Fact and its Implications.—The considerations so far submitted in this chapter, as pointing to the existence and influence of final causes in the universe, will be strengthened and completed by a brief analysis of order and its implications.