e. g. seal-R-impression but not impression-R-seal. This is distinguished from Simple Relativity by its emphasis upon the asymmetrical character of the relation. It is limited because the relation is significantly internal to only one term; and it is particular because all the relations sustained by the other term are not external. Kant's categories and Plato's ideas represent this type of relativity. Universally Limited Relativity is a-R-b but not b-R-a, and for every value of x, it is false that r-R-a, e. g. where a is the Absolute upon which all else depends but which itself is independent or unaffected by anything. This type includes the Indian Brahman and the absolute of Plotinus. Selective Relativity is a-R-some b, e. g. sense of sightR-some light rays. Here Kantian epistemology and specific methods, such as the scientific and the mystical, are typical. These forms of Metaphysical Relativity, i. e., relativity in the nature of the real or being, have corresponding forms of Epistemological Relativity because experience or knowledge is just as real, and just the same sort of reality, as anything else. With respect to the relations between the so-called metaphysical and epistemological realms, simple relativity may be called Mediary Relativity, a-R-b where a is some medium, such as air or light rays, between the knower and the known, and b is the resultant knowledge. Mediary relativity has the forms of Physiological Relativity where a is part of the knower's body; Psychological Relativity where a is the nature of the mind; Pragmatic Relativity where a is the interests, desires, temperament of the knower; and Historical Relativity where a is tradition, education, the political and economic conditions, and such factors of historical epochs as influence judgment or appreciation. This classification is, of course, more or less arbitrary, and itself relative. Chronologically, the absolutistic attitude precedes the relativistic. Primitive man, who represents a stage in human evolution including, according to future historians, the twentieth century, seems naturally inclined to absolute explanations. Largely because of his desire to utilize the beneficent, and placate the malevolent, forces about him, man has been so eager for absolute knowledge that often he has almost deliberately deceived himself into believing he possessed it. Even the civilized man can refuse to look through the telescope for fear his faith may be shaken. Negative instances are notoriously difficult of observation. The Vedic sacrifice is master even of the god of thunder; and if one tithes and sits in the pew on Sunday, one fears not death. Moreover, the definiteness and convenience of the simple, unconditioned explanation favors the absolutist tendency. Man's limited experience and his insensibility to the infinite complexity of fine distinctions led him to consider absolute the aspect of things as seen from his usual point of view. The earth is flat, for we have seen it so with our own eyes. The fundamental substance is water, or air, or spirit, or electricity. One can see that Euclidean geometry alone is valid. The earth is at rest;no, it moves and the stars stand still;-well, you can take your choice! Thus, seeing things in an increasing variety of aspects or relations has changed our judgments and heightened our sense of the dependence of our judgment upon our particular point of view. All viciousness or subjectivity in this conception of relativity is circumvented by the denial of any substantial distinction between the subject and the object, by the recognition that particular points of view are just as spacio-temporal and just as spiritual when they are our own as when they are the moon's. The pre-Socratic hylozoists and the unsophisticated Sophists, with their helmsman in Heraclitus, started phil osophy on a tack which might have kept Western culture out of the doldroms in which it drifted for two thousand years had not Socrates and Plato brought about a calm so absolute that even Aristotle could not keep his sails inflated. The Milesian school explained reality equally well by taking as their point of reference any stage of the world-process such as water, air, or the boundless. In terms of this more or less arbitrarily chosen absolute all else had its being and could be known. Like Thales, Pythagoras, too, was more relative than he knew, for before Einstein the Pythagoreans "put the world in numbers." The anti-anthropomorphism of Xenophanes, the fiery flux of Heraclitus, and the manmeasure doctrine of Protagoras proved too much for the traditional absolutism which, with respect to religion, morality, and the state, would let well-enough alone. Instead of accepting relativity and beginning a collection and classification of aspects, Socrates and Plato soared into the heavens in quest of an absolute pattern for the whole, and the parts, of a perfect and unchanging city-state. They graciously granted Heraclitus his flux. Things are changing and relative, but things are imperfect and lacking in reality. Just here Aristotle almost saw that ships could sail in spite of Platonic calms. Nothing for him was more real than the particulars; their perfection was relative to the unique potentialities which resided in the nature of each. Your Golden Mean could not be mine. Matter and form, even primitive matter and pure form, potentiality and actuality, non-being and being, like genus and species, are instances of mutual relativity. In the first pages of the De Motu Animalium, chiefly, the assumption that only the immovable could create movement kept him from the conception of the relativity of motion. Yet Aristotle had spent too many years in the Academy not to finish by assuming an unmoved mover and the immortality of species. The attention was again shifted from identities to differences by the Cyrenaics, whose psychological and epistemological relativity was continued by the Epicureans. Yet, as in all of these early relativistic views, something like the Epicurean atoms forms a background of absolutistic assumptions. This fact is implied by the very name of the last representatives of this tendency in Greek thought, the Sceptics. It is latent in the concept of probability as developed by Carneades. The Sceptics of the first century of the Christian era contributed to the evolution of relativity by arguing that a cause is a relatum which can neither be syncronous with, nor precede or follow, the effect. Here the argument waited for David Hume. In passing, one may remember the beautiful characters of Arcesilaus and Carneades, a consequence, perhaps, of their philosophy. Throughout the Middle Ages the concept of relativity awaited the conquering of the unexperienced minds of Western Europe by the centered might of Christian and Platonic absolutism. The relativistic attitude, however, was never entirely absent. Even mysticism has more significance here than appears at first sight. It bears witness for relativity not only negatively in the extent of the world against which it turns its back, and in its opposition to the formulated dogmatism of the period, but also positively in its ready acceptance, as Hocking expresses it, of "a present inspiration as its law." Among the intellectuals this same tendency was kept alive by the growing emphasis upon nominalism. The conception of the relativity of perception and of knowledge was chiefly responsible for the new view of the world created by such minds as Nicolaus of Cusa, Copernicus and Giordano Bruno. Burnt offerings of living men were sacrificed on the altar of the absolute that a Galileo, a Kepler, and a Newton might live and think. Here at the dawn of science the evolution of rela1The Meaning of God in Human Experience, New Haven, 1923, p. 400. tivity was rapid, and culminated in Newton's formulation of the relativity of motion. Yet even Newton was unable to trust his insight, and postulated absolute space, time, and motion. He showed, however, that the followers of a creative mind may be more dogmatic than their master. Newton said that he was only like a boy playing on the seashore, and diverting himself in now and then finding a smoother pebble or a prettier shell than ordinary, while the great ocean of truth lay all before him." And Einstein, making a substitution for Descartes's name in another of Newton's remarks, might say, "If I have seen farther than Newton, it is by standing on the shoulders of giants."" Here I can but mention the steps in the evolution of relativity through the dogmatic abduction of the scientific methods by Descartes, Spinoza, and Leibnitz; through English empiricism and scepticism with its almost complete emancipation from religious absolutism; through German criticism and idealism with its reserve strategy making the last stand against the allied relativistic forces of individualism, positivistic philosophy, psychology, and science; the pragmatic and neo-realistic attitudes of mind; and the development of mathematical theory and scientific experimentation, particularly non-Euclidean geometries and electro-magnetic and optical hypotheses. In science the flower of this evolutionary growth is the theories of Einstein, Einstein's accomplishment is chiefly a synthesis of the results of many different fields of investigation. It deserves the name of physical relativity because of the fundamental role played by the mutual relativity of time and space and the absolute relativity of motion. This is a physical and metaphysical relativity because the real nature of things or events varies with their 2Cf. W. T. Sedgwick and H. W. Tyler, A Short History of Science, New York, 1917, p. 300. 3 Loc. cit. |