Catholic Encyclopedia (1913)/Mechanism
There is no constant meaning in the history of philosophy for the word Mechanism. Originally, the term meant that cosmological theory which ascribes the motion and changes of the world to some external force. In this view material things are purely passive, while according to the opposite theory (i. e., Dynamism), they possess certain internal sources of energy which account for the activity of each and for its influence on the course of events; These meanings, however, soon underwent modification. The question as to whether motion is an inherent property of bodies, or has been communicated to them by some external agency, was very often ignored. With a large number of cosmologists the essential feature of Mechanism is the attempt to reduce all the qualities and activities of bodies to quantitative realities, i. e. to mass and motion. But a further modification soon followed. Living bodies, as is well known, present at first sight certain characteristic properties which have no counterpart in lifeless matter. Mechanism aims to go beyond these appearances. It seeks to explain all "vital" phenomena as physical and chemical facts; whether or not these facts are in turn reducible to mass and motion becomes a secondary question, although Mechanists are generally inclined to favour such reduction. The theory opposed to this biological mechanism is no longer Dynamism, but Vitalism or Neo-vitalism, which maintains that vital activities cannot be explained, and never will be explained, by the laws which govern lifeless matter. As Mechanism professes to furnish a complete system of the world, its extreme partisans apply it to psychical manifestations and even to social phenomena; but here it is at best only tentative and the result very questionable. Its advocates merely connect, more or less thoroughly, psychological and social facts with the general laws or leading hypotheses of biology. It is preferable, therefore, in the present state of our knowledge, to disregard these features of mechanistic doctrine, which are certainly of a provisional character. In a word then, Mechanism in its various forms shows a tendency to interpret phenomena of a higher order in terms of the Lower and less complex, and to carry this reduction down to the simplest attainable forms, i. e. to those quantitative realities which we call mass and motion. Psychology and sociology derive their explanation from biology; biology derives its explanation from the physical and chemical sciences, while these in turn borrow their explanation from mechanics. The science of mechanics becomes by a very simple process a particular phase of mathematical analysis, so that the ideal of Mechanism is Mathematism, that is to say, the representation of all phenomena by mathematical equations. Hence it is plain that Mechanism tends to eliminate from science and from reality all "qualitative" aspects, all "forms" and "ends". We shall first state the arguments brought forward in support of the theory, and then subject it to criticism.
(1) Modern Mechanism, which unquestionably goes back to Descartes, arose, it is said, from a legitimate reaction against the errors of decadent Scholasticism. The latter had abused the old theory of forms and latent qualities. Whenever a phenomenon called for explanation, it was furnished by endowing the substance with a new quality; and, as Molière jestingly puts it, "the poppy made one sleep because it has the sleep-inducing property". Each thing was what it was by virtue of an appropriate form; man by the human form, a pebble by its pebble form; and each thing performed its characteristic functions by some "virtue". Thus, it is alleged, all explanations fell into tautology, and science was doomed a priori to pursue a monotonous round in complete sterility. If Mechanism did nothing more than deliver us from this absurd logomachy, it would possess at least a negative value, emphasizing by its opposition the weakness of qualitative explanations.
(2) The general laws of applied logic are cited in favour of the principles of Mechanism. The scientific fact is not the initial fact of observation. The scientist is not satisfied with seeing, he must understand; and the only way to understand is to explain. Now there is but one conceivable method of explaining the new reality; the things which are not understood must be reduced to known antecedents. The barrenness of formal and final causes is, according to the Mechanists, at once manifest. The form is what makes a thing what it is, but the fact or thing which is to be explained does not become intelligible by reason of its being what it is. Therefore, to allege the form as an explanation is to explain a thing by itself. The interpretations based on "ends" are not more productive of scientific results. Aside from the anthropomorphic illusions to which such interpretations are liable, the ends help us no better than the forms to avoid tautology. The end of a thing is only the action towards which it tends, the term of its development. But this action and this term can be known only through further observation; they constitute new facts which require an explanation of their own. We learn nothing from them as to the nature of the original thing; they do not tell us how or by what internal factors it performs its action or reaches its term. To explain the eye by declaring that it was made to see, is to state that it is an eye but nothing more. To understand the eye it is necessary to know by what internal structure, and under what sort of stimulation the organ performs its visual functions.
Hence, say the Mechanists, all ends and final causes must be banished from scientific systematizations. The unknown can be explained only by reduction, to the known, the new by reduction to the anterior, the complex by reduction to the simple. Now, if we look for the only genuinely scientific explanation, we cannot stop until we reach mass and motion. Such indeed is human intelligence, that we first grasp the most general and the simplest realities, and we grasp these the best. Take for example the very general phenomenon of life. To explain it by a vital force or principle would simply be not to explain it at all. We must, if we would understand life, reduce it to something which is not life, to something simpler and better known. We must therefore, the Mechanist asserts, have recourse to the physical and chemical phenomena, and our understanding of life is measured by the possibilities of this reduction. It may be that we have not explained by this method everything connected with vital phenomena, since their reduction to physical laws is as yet incomplete: but this does not justify the assumption of a latent quality; it only means that our biological knowledge is far from perfect. Chemical phenomena and physical qualities must likewise be accounted for. Under pain of fruitless tautology, we must reduce them to that which is already known. But we find here only quantitative matter and motion, realities which may be reduced to mathematical formulæ, thus bringing us to a practically pure idea of quantity. Beyond this we cannot go, for if we suppress quantity our mind loses all hold on the real. It apparently follows that by the very requirements of logic, Mechanism alone has an indisputable claim to a place in the realm of science. Any other system, the Mechanists claim, must necessarily be provisional, tautological, and therefore misleading.
(3) There is another consideration which is said to outweigh all reasoning a priori: Mechanism succeeds. Its explanations, we are told, are clear and precise to a degree unattainable in any other theory, and they satisfy the mind with a synthetic view of reality. They alone have delivered us from an intolerable pluralism in the cosmic system, secured that unity of thought which seems to be an imperative need of our mind, and brought under control phenomena which had defied all analysis and which had to be accepted as primary data. Furthermore, the doctrines of Mechanism have enabled us to anticipate observation and to make forecasts which facts in nature have actually confirmed. Herein is a guarantee which, for the Mechanists, is well worth all theoretical proofs. Such, in the main, is the line of reasoning followed by the adherents of Mechanism. That it is not conclusive will appear quite clearly from the following examination into its value.
It cannot be denied that mechanistic ideas have played a useful and creditable part in science. Whatever one may think of the Cartesian revolution in the realm of philosophy, it has certainly stimulated research in the scientific field. This service cannot be overlooked, even though one be convinced of the inability of Mechanism to provide us with a formula of the universe. It is none the less true, however, that Mechanism as a cosmic theory must be rejected.
(1) First of all, there is in the progress of natural phenomena a fundamental fact which Mechanism is unable to account for, the irreversibility of cosmic events. All motion is reversible: when a moving object has covered the distance from A to B, we at once understand that it can go back over the path from B to A. If, therefore, everything that happens is motion, it is not clear why events in nature should not at times retrace their march, why the fruit should not return to the flower, the flower to the bud, the tree itself to the plant and finally to the seed. True, it is shown that this reversion, even in the mechanistic hypothesis, is exceedingly improbable, but it would not be impossible. Now such reversion, in the case of certain phenomena at least, is more than improbable; it is inconceivable, for instance, that our limbs should be bruised before the fall which causes the bruise. This irreversibility of cosmic processes is undoubtedly, as the Mechanists themselves admit, the chief difficulty against their system.
(2) When we enter within the field of biology, the difficulties against Mechanism multiply. Granted that this doctrine has served as a guide to many successful investigators, what have they attained in the last analysis? They have not advanced one step nearer to the "formula of life." All the biological facts so far examined and understood have been brought into the category of physico-chemical activities — indeed, this might have been expected; but that is not life. A particular phase is isolated for examination, and the characteristic mark of life is thereby destroyed. For that which characterizes life experimentally considered, is the unity, the solidarity of all these particular activities; all converge to one common purpose, the constitution of the living being in its undeniable individuality. Its explanation surely cannot be found in disintegrating it by analysis. The conflict with Mechanism has now been carried into the experimental field, and the last few years have yielded an ever increasing number of observations which seem to defy all mechanistic reduction. These are chiefly concerned with abnormal conditions which are brought about during the first stages of individual development. Sea urchin embryos, taken when they have progressed far enough to permit the determination of the normal growth of each part, and divided into two or three segments, produce as many animals as there were artificial segments. Must not the conclusion be that there exists in each embryo a simple principle — an entelechy as Driesch says, using Aristotle's term — which is one in the whole organism and is entire within each part? Is not this the very contrary of Mechanism which claims to reduce everything to the movements (interwoven of course, but really independent) of the parts? It is not surprising, therefore, that the adherents of neo-Vitalism should now be numerous, and that their ranks are growing fast.
(3) But it is principally before logical and philosophical criticism, that Mechanism seems to give way completely. Those very ideas on the nature of explanation, according to which it is attempted to reduce all reality to terms of the supposed primary notions of mass and motion, preclude Mechanism from ever attaining the whole of reality. The present must be reduced to the past, the new to that which is already known, the complex to the more simple; but this original datum remains, that the complex and the simple are not identical, that the new fact is not the fact which was already known. If we suppose all that was contained in the complex to have been reduced by analysis to simple elements already known, we have still to explain their combination, their unity in the complex; and it is just these that have been destroyed by the explanatory analysis. Given that there is something to explain, something unknown, it is clear that there is something beyond the known and the old, and there must inevitably be some principle which moulds into unity the numerous elements, and which either for the species or for the individual, may in a very broad sense be called the "form". Explanations based on analysis do not discover the form, because they begin by destroying it. It may be said, in a particular but entirely acceptable sense, that "form" explains nothing, because to explain is to reduce, and form is by its very nature irreducible. But from this to the denial of form is a very far cry. The scholastics of the decadent period erred in regarding forms as explanatory principles, but Mechanism distorts the reality by reducing it to its "matter", by ignoring its specific and its individual unity. For the same reason, the mechanical interpretations of the dynamic aspect of things, that is to say of cosmic evolution, prove futile. It is of course instructive in the highest degree to know what previous state of the universe accounts for the present state of things; but to look on those anterior efficient causes of things as the adequate representations of their effects, is to lose sight of the fact that these latter are effects, while the former were causes; the consequence is an absolute "statism" and a denial of all causality.
Similar observations might be made on the subject of final causes. The meaning itself of the word finality has undergone singular changes since Aristotle and the thirteenth century. Let it suffice to note that finality has its basis in the intellectual nature of an efficient cause, or in the internal tendency of a form viewed from the standpoint of activity, of dynamism. The decadent Scholastics weakened their position when they relied on forms and ends only as means of scientific explanations strictly so called, while Mechanists are clearly in error when they seek in these same scientific explanations for an account of reality to the exclusion of forms and ends. More might be said of the manifest inadequacy of quantitative images, of cosmological Mathematism which reduces all continuity to discontinuity and all time to coincidences without duration, and of the anti-mechanistic reaction which asserts itself under the name of Energism, and with which the researches of Ostwald and of Duhem are associated. But these are complex and general problems. We may now resume and draw our conclusions.
Mechanism is a cosmological theory which holds that all phenomena in nature are reducible to simple phenomena in such a manner that the ultimate realities of the material world are mass and motion. This system has rendered signal service; it exhibits in great clearness the material causes or phenomena; indeed, this explains why its formulæ may, in exceptional cases, provide a formula applicable to some fact as yet unknown. But it is impossible to regard Mechanism as a real representation of our universe. It wrought its own ruin when it claimed a scope and a significance which are denied it by the reality of things and the exigencies of logic.
All general treatises on philosophy give at least a few pages to Mechanism. See also: MERCIER, Psychologie, I (Louvain, 1905); NYS, Cosmologie (2nd ed., Louvain, 1906); TILMANN PESCH, Die grossen Welträtsel (Freiburg, 1907); GEMELLI, L'Enigma della vita e i nuovi orizzonti della biologia (Florence, 1910); OSTWALD, Vorlesungen über Naturphilosophie (Leipzig, 1905); DRIESCH, Der Vitalismus als Gesch. u. als Lehre (Leipzig, 1905); DE MUNNYNCK, Les bases psychologiques du Mécanisme in Revue des sciences philos. et théol. (Kain, Belgium, 1907); BRUNHES, La Dégradation de l'Energie (Paris, 1908).
M. P. de Munnynck.