THE PHILOSOPHICAL ASPECTS OF THE PRINCIPLE OF RELATIVITY

THE PHILOSOPHICAL ASPECTS OF THE PRINCIPLE OF RELATIVITY
Alfred North Whitehead [1]

The most obvious contribution of the scientific doctrine of Relativity to the problems of philosophy is to strengthen the type of argument on which Berkeley relied. Accordingly, those systems of philosophy which rely on this type of argument thereby receive additional support. I will endeavor to explain my meaning, but I am painfully conscious that it would have been better to have had the grounds of this evening's discussion laid out by an adequately trained philosopher.

I presume that the fundamental position of idealism is that all reality can be construed as an expression of mentality. For example, I suppose that Mr. Alexander is a realist because for him mind is one among other items occurring in that evolution of complexes which is the very being of space-time. On the other hand, Mr. Wildon Carr is an idealist because he finds ultimate reality in the self-expression of monadic mentality. The test, therefore, of idealism is the refusal to conceive reality apart from explicit reference to some or all of the characteristic processes of mentality; it may be either drought, or experience, or knowledge, or the expression of valuation in the form of a historical process, the valuation being both the efficient and the final cause of the process. Now Berkeley's argument in favor of this central position of idealism is that when you examine the objects of sense-perception they are essentially personal to the observer. He enforces by a variety of illustrations the doctrine that there is nothing left when you have torn die observer out of the observation. The planet, which is no bigger than a sixpence, is the observer's planet, and he walks off with his own property.

It stands to reason that modern relativity strengthens this argument, since previously there were two elements in our experience which the argument did not touch, I mean space and time. Berkeley's argument rests on the basis that appearances in space and through time are personal to the observer. But space and time were left as common facts. But now it has been shown that space and time cannot be excluded from the scope of Berkeley's argument. Accordingly, you can no longer meet the argument by showing that there are exceptions to it. Hence, so far as idealism is concerned with the facts of nature—and it must be concerned with them—its characteristic type of argument has been strengthened by the recent scientific bombshell. The realist is now left hugging the multiplication table as die sole common fact untouched by each immediate expression of mind. But the multiplication table is no good to a realist. It shuts him up with Plato's ideas, out of space and out of time, which is just where he does not want to be—poor man, like Wordsworth and the rest of us, he wants to hear the throstle sing.

We seem to be left, then, with the idealist position that nature is nothing else than a common expression for diverse processes of mentality. I do not believe that this is die sole choice; I have been trying to sketch in a few sentences the line of thought according to which relativity strengthens the argument for idealism. But, before proceeding, the immediate moral that I want to draw is that Berkeley must be stopped at the very beginning. The presupposition of the whole line of argument must be challenged. Later on there is no resting place.

Let us now begin again and scan carefully the main point of Berkeley's argument.

He attacks the presumption that we observe subjects as qualified by attributes, subject and attribute being independent of ourselves. He easily—ridiculously easily—establishes this point so far as it goes, and it is the scope of this argument which is widened by the modern doctrine of relativity in physical science, so as to include time and space. The exact conclusion which we ought to draw, and must draw, is that the form of thought of a two-termed relation of predicate to subject imposed by the Aristotelian logic is not adequate to express the immediate deliverance of observation. A wider relativity is necessary in the sense that the fact of nature observed—the crimson cloud, to take another of Berkeley's examples—cannot be expressed in terms of the two factors "crimson" and "cloud." In other words, the proposition "the cloud is crimson" is in reality a highly elliptical form of expression and is meaningless unless the suppressed factors are supplied. In practice these suppressed factors always are supplied; in truth they are so obvious to us that it is difficult for us to believe that language has shirked its job of exposing the fact.

Furthermore, everyone would agree that in some sense the suppressed factor includes the observer. Berkeley's argument is that it stands in the essential nature of the case that different observers perceive different things. Accordingly, in the realm of things observed there can be nothing common to diverse observers. Accordingly, there is no common realm of things observed, whose interrelations can be expressed apart from reference to observers. Accordingly, the only common ground for observers is the common stock of abstract ideas which they individually apply to their diverse experiences. Furthermore, these diverse experiences now lose all claim to any objectivity other than that of being phases in the process of the self-development of the observer.

Now I see no escape from this argument provided that the concept of an "observer" is not ambiguous. Unfortunately, it is very ambiguous. Berkeley—tacitly presupposing the Aristotelian logical forms—has thereby presupposed that in the fact observed there can only be the two-termed relation of predicate to subject, for example, "crimson to cloud." Accordingly, for him the additional factor introduced must be something underlying and in a sense creating the realm of the observed. This additional factor is, accordingly (for Berkeley), the mentality of the observer which is expressing itself in these observations. In other words, for Berkeley the observer is mind, and therefore Berkeley is an idealist. But when a realist admits that—as above—the suppressed factor includes the observer, he is (or should be) using the term "observer" in a quite different sense. He is thinking of the observer's body. I do not think that for the exposition of the realist position the term "observer" is at all well-chosen. I put it in, to start with, because, after all, Berkeley started the whole train of thought, so that the idealists are entitled to the initial phraseology which suits their line of development of the argument. But whereas Berkeley puts in an additional factor, namely, mind, which underlies the whole realm observed, the additional factor added by the realists consists of other items within the realm observed. Among these other items is the body of the observer, and this is why a realist carelessly, and in a loose unsatisfactory sense of the term, may assent to the statement that the additional factor includes the observer.

But note that now the realist has admitted that the simple proposition, "the cloud is crimson," is a meaningless statement about nature unless other items of nature are implicitly included in the proposition. In other words, a fact of nature cannot be expressed in the simple two-termed relation of - predication which is the standard form of the Aristotelian logic. In allowing that it is essential to add other items of nature to crimson and the cloud in order to express the immediately apparent fact, he has admitted that the essential facts of apparent nature involve irreducible relations of more than two terms. Owing to the influence of training and custom, as embodied in the phraseology of philosophical literature, it is habitual to us to presuppose that all relations-even if they are not that of predication—are two-termed, and to acquiesce in arguments which tacitly make this presupposition. Accordingly, it is the more necessary for me to emphasize this point, since I consider that, apart from this admission of irreducible many-termed relations, there is no escape from the full force of Berkeley's argument.

If you ask how many other items of nature enter into the relation of crimson to cloud, I think that we must answer that every other item of nature enters into it. At first sight, this would appear to make knowledge impossible for poor finite human beings. But we can classify grades of relata in this multiple relation which I term that of crimson to cloud. The lowest grade sweeps all nature into itself. It is the grade of relata whereby all nature expresses its patience for this relationship of crimson to cloud. There is no such thing as crimson lone and by itself apart from nature as involving space-time, and the same is true of cloud. The crimson cloud is essentially connected with every other item of nature by the spatio-temporality of nature, and the proposition, "the cloud is crimson," has no meaning apart from this spatio-temporality. In this way air nature is swept into the net of the relationship.

You may put it this way, nature as a system is presupposed in the crimsonness of the cloud. But a system means systematic relations between the items of a system. Accordingly, you cannot know that nature is a system unless you know what these systematic relations are. Now we cannot know these systematic relations by any observational method involving enumeration of all the items of nature. It follows that our partial knowledge must disclose a uniform type of relationship which reigns throughout the system. For if we do not know that, we know nodiing: and there is simply nothing to talk about. For example, we should have no reason to believe that there is an interior to the earth, or any lapse of time applying to it. We ask whether this interior is occupied with condensed matter or is empty, and whether this matter be hot or cold, solid or gaseous, because we know that the uniform systematic spatio-temporal relations must supply entities which have the status of forming the interior of the earth.

I call this principle, by which a systematic nature is known to us, the uniform significance of events. This uniform significance is disclosed to us as expressing the patience of nature for every item of our experience—for example, the crimsonness of the cloud.

Another grade of items in the relationship "crimson to cloud" entirely lacks the uniformity which attaches to the first grade. Accordingly, in contrast to "uniformity," I will speak of its "contingency." The principle of the contingence of appearance means that a set of items of nature are presupposed in the relationship crimson to cloud, whose status in the relationship requires detailed examination in each particular instance; though the laws of nature enable us to make a shrewd guess at the types of status which are possible. But there is one item in this contingent grade which is so preeminent that it almost deserves a whole grade to itself. I mean the observer's body. It is an empirical fact, which in no way seems to enter into the character of knowledge as such, that our knowledge of nature consists of knowledge of those relationships for which our bodies are important members of the contingent grade of items. The cloud is crimson, as perceived by a person B, because B is aware of a certain multiple relationship involving processes within his body and other items of nature. We may put it in this way, that B is aware of nature from the standpoint of his body. Thus the relativity to an observer is dominated by the physical state of the observer's body. It is therefore relative to his body.

Apart from the empirical fact that it so happens, I cannot convince myself that the character of awareness of nature necessarily involves this reference to the observer's body. In the first place, it is quite easy to imagine an infinite observer, such as God, whom in this connection I call infinite as being impartially aware of all relationships of items within nature. Each one of us is a finite observer because we are only aware of that selection among the relationships which are dominated by our body. But I cannot see that idealism would gain even if this reference to the body were absent. We can imagine that the perceptions of the sociable archangel, as he chatted with Adam and Eve in the garden, were not from the standpoint of his body, because he had no body, but that his selection of relationships observed was made on some other principle. What is essential as an argument for realism (under this heading of relativity) is that the relationships observed should form a closed system whose characters refer to each other.

There is a process of nature which is obstinately indifferent to mind. This is why I feel difficulty in assigning to mind, or knowledge, or consciousness any essential role in the flux of fact—essential, I mean, beyond the roles played by other abstractions from that flux, such as chairs and tables.

I cannot persuade myself that relativity in any way weakens this obstinate indifference of nature. It simply shows that there are more various relationships within nature than we had anticipated—no new discovery, for every advance of science adds to the complexity of nature. If Einstein had established the affirmative answer to Pope's question, "Shall gravitation cease as you go by," he would have done something to advance the claims of idealism. But all he has done is to make it more difficult for us to compare our watches with those of the inhabitants of Mars, entirely owing to circumstances over which we have no control; and also he has produced a law of gravitation more complicated than that of Newton—but, again, this law depends on circumstances over which we have no control. I don't see how it is any easier to bend space now than it was to alter the strains and stresses in the ether. Accordingly, I cannot appreciate what accession there has been to the arguments on behalf of idealism. We still find mental processes faced with an obstinately independent nature, so that the correlations of mental processes with natural processes appear as unessential for the course of natural events. I am not denying that there are such correlations, or that when they occur the natural and the mental are not the same fact with different aspects of it emphasized. But what I am denying is that some correlation with mentality can be proved to be essential for the very being of natural fact. I will summarize the foregoing discussion by saying that the modern doctrine of relativity is calculated to hearten idealists by emphasizing certain of their lines of argument, but that it does not essentially touch the validity of the controversial arguments as between the two sides.

I should, however, not like it to be concluded that I am maintaining that relativity has no philosophical importance. The general character of its importance arises from the emphasis which it throws upon relatedness. It helps philosophy resolutely to turn its back upon the false lights of the Aristotelian logic. Ultimate fact is not a mere aggregate of independent entities which are the subjects for qualities. We can never get away from an essential relatedness involving a multiplicity of relata. Every factor A, discerned as an entity within fact, expresses in its very being its capacity for the relationships into which it enters, and requires that all other factors of fact should express their capacities as relata in relationships involving it. This is the doctrine that any factor A is significant of the relationships into which it enters, and that conversely all factors within fact must express the patience of fact for A.

The more special aspect of the importance of relativity in philosophy is its treatment of space and time, particularly time. Space and time can never be mere side shows in philosophy. Their treatment must color the whole subsequent development of the subject. The relational treatment of space is a well-established principle, and I doubt whether relativity has made much difference here, so far as philosophers are concerned. But it has made an immense difference to the treatment of time. The unique serial character of time has gone by the board; also a thoroughgoing relational treatment of time is now necessitated and made possible. I am told that there are phrases in Aristotle which look that way. Am I right in recollecting that he defines time as an ordering or disposition of events in respect to each other?

Furthermore, the fusion of time with space and the dropping of the unique seriality involves the necessity of looking on ultimate fact as essentially a process. Accordingly, wherever the idea of "process" has been lost, we are dealing with a very advanced type of abstraction. This is why, in treating this subject, I have always insisted that our lowest, most concrete type of abstractions, whereby we express the diversification of fact, must be regarded as "events," meaning, thereby, a partial factor of fact which retains process.

Now I conceive that nothing of this is really new in philosophical thought. It is as old as the hills. But I still think that a scientific doctrine which enforces consistent emphasis on these ideas has the utmost importance for philosophy, even although it does not settle the established controversies between realism and idealism.

[1] Proceedings of the Aristotelian Society, V. 22, 1921-1922, pp, 215-223.