Elements of metaphysics

by A. E. Taylor

In a society of finite individuals with interrelated aims and objects, each of the individuals can only attain satisfaction for his own subjective interests by some degree of concerted action along with the rest. And concerted action is only possible where the co-operating individuals can reduce their various views of their common external environment to common terms, equally intelligible to all, and similarly indicate to each other their respective special contributions to the common task. There must be a common understanding of the difficulty to be met, and of the precise part each is to play in meeting it. Thus intercommunication between individuals is an indispensable requisite of all effective practical co-operation.

But again, intercommunication is only possible by means of description in general terms. Only in so far as there are identical elements in the experiences of the various individuals can one communicate the contents of his experience to another. Immediate feeling, precisely because of its unique individual character, is essentially incommunicable. Thus in communicating information about my own body to another, I am of necessity forced to speak of my body in terms not of the immediate experience I have of it in organic sensation, but of those complexes of sense-presentations which he and I alike get through our organs of special perception. And so the whole physical order can only serve as a basis of co-operation between individuals so far as it is describable in the last resort as a complex of sense-presentations equally accessible to the observation of all the individuals. Any kind of experience of nature which is uniquely peculiar to myself, and therefore incapable of being got under assignable conditions by any other individual endowed with the same organs of perception, is necessarily incommunicable, and therefore useless as a basis for concerted action. Hence science is restricted by its very purpose to describe the physical order in such a way that its descriptions may be available for the objects of practical art, to the description of it in its phenomenal aspect as a mere complex of related presentations or possibilities of presentation. It is no accident, but a logical consequence of the conditions of intercommunication, that all scientific description must start from and end with occurrences of the phenomenal order which any individual may experience by conforming to the prescribed conditions of perception. Thus we see that it is an epistemological characteristic of the physical order as investigated by science, that it consists exclusively of those objects which are, in principle, perceptible by more than one individual. If there are objects in their own nature incapable of being experienced by more than one individual, such as, e.g., my own inner life, those objects cannot belong to the physical order of science.[^[162]]

§ 3. There is a second purpose of description which arises out of the first as human experiences become more reflective. Description not only enables me to communicate the particular situation of the moment to others, and devise in concert with them means for coping with it; it also enables me to formulate beforehand general rules for my own behaviour in recurrent situations of the same type. The need for the possession of such general views originates, of course, while description is still confined to its original function in assisting social co-operation. From the practical point of view of those industrial arts out of which our various physical sciences have arisen, it is an economical advantage of the first magnitude to be able once and for all to formulate a general rule for dealing with the indefinitely numerous occurrences of typical situations, instead of having to deal with each occurrence separately as it arises.

The advantages of such general rules speedily make themselves felt in the increased power and importance enjoyed by the section of society which is in possession of them, a consideration which may help us to understand why, in early stages of civilisation, such rules are commonly jealously guarded as the hereditary secrets of close corporations.[^[163]] Thus it comes to be the special aim of scientific description to assist the formulation of general rules for the practical manipulation of the objects of the physical order. And, with the progress of reflection, this originally secondary object of the descriptive process becomes to a large extent independent of the primary object of intercommunication. Even where I have no need or no desire for intercommunication and co-operation with my fellows, it becomes my interest to seek generalised descriptions of typical situations in the physical order as the basis of practical rules for my own voluntary intervention in that order.

§ 4. The interest in the formulation of general rules for practical interference with nature, again, necessarily dictates the form which our scientific descriptions will take, and is thus the source of those practical postulates of empirical science with which we have already made some acquaintance. It compels us to assume, in the first place, as an indispensable condition of success in our descriptions, that there are situations in the physical order which may be treated with sufficient accuracy for our practical purposes, as recurring identically; in the second place, that, so long as we abstain from intentional intervention in the course of events, they succeed one another in a fixed routine order, or, in other words, that there are no departures in nature from established routine of such a kind as to interfere with our calculations; in the third place, that every event in the physical order is, within the limits requisite for our successful devising of means to our ends, determined by antecedent events. It is thus our interest in obtaining general rules for the production of effects in the physical order by intentional interference with it which is the source of the three fundamental postulates of empirical physical science, the postulates of uniformity, of the omnipresence of routine or mechanical “law,” and of the causal determination of subsequent by antecedent events.

The dependence of physical science upon these three fundamental postulates thus does not prove their ultimate truth, as we have already shown at length in preceding chapters: it proves only that where they cannot be treated as approximately true, within the limits in which their falsity could be detected by sensible experiment, our special interest in devising rules for the manipulation of events cannot be gratified. Conversely, wherever that interest can be successfully gratified, these postulates must be for all practical purposes equivalent to the truth. Hence, if we remember that the ultimate object of all physical science is the successful formulation of such practical rules for action, we can see that it is a logical consequence of the character of the interests which dominate our scientific descriptions, that the physical sciences should adopt a rigidly mechanical view of the physical order. Only, in proportion as any one branch of physical science succeeds in carrying out in detail this conception of the physical order as an interconnected mechanism of sequences rigidly determined by laws of sequence, does it succeed in effecting the purposes by which all physical science has been called into existence. We may thus call the mechanical conception of the physical order the most general postulate of physical science. Only, we must once more take care to recollect that a fundamental postulate of physical science need not in the least be an ultimate truth; such a postulate is in the end nothing more than a way of stating the nature of the interest which physical science subserves, and, as we have sufficiently seen, that interest is not the purely logical one of consistent thinking, but the practical one of successful interference with nature.

§ 5. It does not, of course, follow that all the sciences which deal in any way with the events of the physical order can as a matter of fact carry out this mechanical view of their objects with equal success. It is only in the various branches of abstract Mechanics that we get anything like complete systematic adherence to the postulates of the mechanical theory of physical nature as previously enumerated. For the physical, chemical, and still more for the biological sciences, it remains an unrealised ideal—and one we have no right to think ever completely realisable—that all the facts of electrical and chemical, and again of physiological process should be ultimately capable of reduction to routine uniformities upon which confident calculation and prediction can be based.

Thus, even in Chemistry, limits are set to the successful adoption of the purely mechanical point of view, by the fact that chemical combination is regularly productive of new qualities in the compound which could not have been predicted from a knowledge of the properties of its constituents, but have to be ascertained a posteriori by actual experiment. It is true, no doubt, that we seem to be increasingly able, as our chemical knowledge advances, to say in general what properties may be expected to result from the combination of given elements, but there is no logical ground for supposing that we shall ever be able to foretell all the properties of an as yet unexamined compound, and in any case such knowledge could only be of a general sort. However much we might know, in advance of the results of the combination of certain elements in certain proportions, it would still be impossible to predict with absolute certainty the precise result of trying the combination in a particular concrete case.

Still less realisable would be the ideal of the reduction of Biology to applied Mechanics. It is not merely that the isolated physiological process regularly exhibits qualitative aspects of a chemical or electrical kind, which we have no right to reduce to mere quantitative changes. Beyond this, as the very terminology of our evolutionary hypotheses is enough to show, it is impossible to state the facts of biological evolution without introducing, under such names as “sexual selection,” continual reference to a subjective factor, in the form of the likes and dislikes, habits and cravings of sentient beings, and this selective factor, being in its own nature incapable of direct presentation in identical form to a plurality of experiences, is not even a member of the physical order. With the case of Psychology we shall be better able to deal in connection with the special discussions of the following Book. (See especially Bk. IV. chap. 1.)

Considerations of this kind seem to necessitate the following general view of the logical character of descriptive physical science. The only science in which the postulates of description are rigidly carried out to their logical consequences is the science of abstract Mechanics in its various branches (Statics, Kinetics, etc.). Mechanics owes its power to follow out these postulates to its abstract character. Precisely because it regards only those aspects of the actual physical order which are consistent with the fundamental postulate of describability by general formulæ, Mechanics is constrained to be a purely abstract and hypothetical science. For since every actual process involves the appearance of the qualitatively novel, and since all concrete quality is in its essence unique, no actual process can be merely mechanical.