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Part 2: Section 5 - Naturalism
DESCARTES STILL RETAINS IN HIS PHILOSOPHY SOME MEDIEVAL modes of thought. Yet he represents on the whole a complete break with medievalism, and was the first great philosopher of modern times to do so. For this reason he is sometimes called the father of modern philosophy. He was himself a distinguished mathematician and scientist. He enthusiastically supported the new scientific spirit of inquiry, especially the mechanical interpretation of nature and the exclusion of teleological explanations from science. Like the actual founders of the scientific movement he did not disbelieve that natural phenomena are ultimately controlled by divine purposes. The view of the founding fathers, which Descartes shared, was that God's purposes are inscrutable, and that in any case a knowledge of them would be useless for the special purposes of science. What are its special purposes? It is often said that the function of science is to predict phenomena and so enable us, so far as possible, to control the future to our advantage. If you could know that an earthquake will occur at a certain place, you could not perhaps stop it, but you could at any rate take precautions against its effects. You could, for example, go to some other place. The science of meteorology aims at enabling you to know when to carry a raincoat. Physics can predict that if you do certain things with uranium you can
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achieve the obviously desirable result of killing a few millions of our fellow creatures.
This. account of the function of science as being concerned only with prediction and control of events is probably an over-simplification. Why assume that science has only one function? But it is at any rate true that prediction is one of its most important aims. And knowledge of the purposes of events is no help in predlctmg them. Perhaps if one were omniscient and knew the entire world-plan as it exists in the mind of God, one might be able to predIct what God will do next. But no one can attain this degree, of knowledge. And it is useless to know merely that the sun exists to gIve men light by day, the moon by night. This will not enable one to foresee an eclipse. Nor will the knowledge that the purpose of rainbows is to remind us of God's promise not again to destroy us by floods be of any use in enabling us to know when and where it will please God to put a rainbow in the sky.
To predict phenomena what you have to know is, not their purposes, but their causes and the physical laws which govern them. If you know the causes of eclipses, and the laws of motion and gravitation, then and then only can you predict them. And it is the same with all other phenomena. The general causes of rainbows are now known. And the only reason why we cannot predict the exact moment and place at which a rainbow will appear is that the meteorological conditions which control them are in particular cases, so complicated that it is impracticable to calculate them.
For these reasons the new science concentrated on causes and mechanical explanations, and excluded teleology. This, of course, dId not prove, nor did the founders of science suppose that it proved, that there is no purpose in nature. How the mechanistic procedures of science gave rise to the conception of a purposeless world has already been explained. But Descartes, in supporting the mechanical interpretation of nature, gave a powerful impulse to the train of thought which led to that conception, and showed himself to that extent on the side of the scientific view of the world.
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Nor was it only that he gave that view his general support. He injected mechanism and naturalism into the details of his philosophy in peculiarly emphatic ways. That he wished to push mechanism, and even materialism, to the limit, appears in his curious theory of animals. Animals, he maintains, are only automata. They act as if they are conscious, but in fact they are not conscious. They are nothing but physical machines. Man alone has a mind. The lamb may appear to be running away from the wolf because it feels fear. But in fact it feels nothing. It is a stimulus response mechanism. Descartes did not, of course, use that language. His physiology was, from a modern pomt of view, crude. But his theory was, in spirit, identical with those modern views which would explain the behavior of animals without introducing the conception of an inner "consciousness". at all. Descartes did not include man in this theory. Men have minds. He believed this because he knew that he himself was conscious, had sensations and thoughts, felt pleasures and pains; and he supposed that other men must be like him in this respect. He would have thought it absurd to deny the existence of consciousness in men, and he therefore left that last extreme of absurdity to the more truly "scientific" thinkers of our own day.
Another motive which doubtless impelled Descartes to make an exception of man was that men are believed to have immortal souls, whereas animals do not have them. If this is so, the soul of a man must be non-material, since otherwise it could not survive the body.
In the end, of course, Descartes' philosophy is duahstlc. The world is made of two radically different kinds of things, matter and mind—or three, if we add God. But he carries materialism and mechanism to the furthest possible limit, stopping short only where they would become, in his view, plainly absurd and unntenable. This is the naturalistic side of Descartes.
We turn now to the religious elements in his system. One of them is his belief in an inner non-physical mind in human beings. It is true that a dualistic theory of human personality can be held without any religious implications. Consciousness might be en-
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tirely non-material, and yet it might not survive the body. The two might be interdependent and come to an end at the same time. But historically belief in a non-physical conscious mind has been loaded with religious implications connected with the idea of the immortality of the soul—which is one main reason why the modern mind, as exemplified by the scientific psychologists of our time, almost universally rejects it. Anything which in any way smells of religion is suspect and cannot possibly be "scientific." Belief in a non-physical mind does not necessitate belief in survival after death. It does, however, leave open the possibility of survival, whereas the denial of it renders survival impossible, or at least extremely unlikely. This is the logical connection between religion and a dualistic view of human personality, and justifies us in classifying Descartes' view as among the religious elements in his philosophy.
The position of God in his system is, however, its really important religious element. It is true that Hobbes who, on our view, is an entirely non-religious philosopher, also "believed in God. But there is a great difference between the two thinkers in this respect. Not that Descartes, any more than Hobbes, shows in his writings any religious feeling. His writing is coldly logical throughhout, as well in its references to God as to anything else. God seems to be for him, as for Hobbes, a mere intellectual abstracction. But in Descartes' system the concept of God is necessary and central. The system would collapse without it; while in the phiilosophy of Hobbes God is an accidental appendage and, in fact, something of a nuisance. Hobbes believed that religion is "a pill which it is better to swallow without chewing." Professor Castell's remark that he "pays lip service to natural theology" hits off the position well. It is not meant that he was only pretending to believe in God. He was probably sincere. He believes that God has to be introduced as the first cause of the world-machine, but having said this he hurries on to what is obviously the only thing which genuinely interests him, the working of the machine itself. God might just as well be left out of his view of the world.
But with Descartes the position is quite different. He tries to
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construct a philosophy on the model of geometry. A system of geometry begins with a set of axioms which are its logical foundations. In Descartes' time the axioms were supposed to be "self-evident truths"—a position now abandoned by mathematicians. The geometrical system proceeds to deduce from the axioms a set of theorems by rigorous logical steps. Descartes thought the same thing could be done in philosophy. His system consists of three main steps. The first is the axiom, "I think, therefore I exist." The second is the theorem, "God exists," which he thinks he deduces by rigorous logic from the axiom. The third is the theorem, "matter exists" which is supposed to follow, again by rigorous logical steps, from "God exists." The details of the suppposed logical steps from the axiom to the first theorem, and from the first theorem to the second, do not concern us here. But there are two points about the scheme which we should note.
The first is that the general result of the argument is to show that the universe consists essentially of three kinds of existences. The first is God. The second is mind-this is evident from the axiom, "I think, therefore I exist," since "I" am a mind. The third is matter.
The second point to note is the reason why the concept of God is essential to the philosophy of Descartes, and not merely accidental as with Hobbes. The proof that matter exists depends on the concept of God. One might ask how this can be the case when the existence of matter is proved by our senses. We see and touch stones and trees, which are material objects. But Descartes beelieved that these objects which we think we see and touch might not "really" exist. They might be no more than apparitions in a lifelong dream. Do we not seem to see and touch material objects in our dreams, while yet these objects do not really exist at all? He thought that the only way of proving that matter "really" exists is first to prove the existence of God. From this it would follow that matter really exists, and is not a dream; since if it were, we should have to accuse God of having given us instruments of knowledge—our senses—which systematically deceive us. This would make God a liar, which is inconsistent with the
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attributes of goodness and truthfulness which Descartes supposed his arguments proved God to possess.
Whatever we may think of this curious intellectual scheme, we see at least that the existence of God is logically necessary to it, and that without it the whole argument and the conclusion to which it leads—that the world is composed of the three things, God, mind, and matter—would fall to the ground, just as a system of geometry would fall to the ground if one of the steps of the chain of reasoning of which it consists were false.
We come now to Hobbes (1588-1679) who, according to our classification, is the first pure representative of the naturalistic or scientific view of the world. So much has already been said of him that we need do little more than summarize our previous comments and add a few points. His conventional references to God may be discounted. His general position in the history of thought is that he is the earliest translator of the new science into philosophy. He simply generalizes from the work of Galileo, Harvey, and other scientific discoverers. His first conclusion is materialism. What Galileo said about physical objects—that they are made of atoms in motion—Hobbes now says about the whole universe. Everything in the universe is made of atoms, and is therefore material. Minds, he holds, as against Descartes, are not non-physical.
Since all changes in the world, that is to say, all events, consist in nothing but changes in the motions of material particles, and since these motions are entirely explained by the laws of motion, Hobbes is necessarily a determinist. "Whatever effect is produced at any time, the same is produced by a necessary cause . . . so that all the effects which have been or shall be produced have their necessity in things antecedent."[1] Accordingly it is often said that Hobbes denied the existence of free will. This is a somewhat doubtful interpretation. But it is certain that he affirmed the rigid determinism which historically produced the denial of free will.
1 Hobbes, Selections, Charles Scribner's Sons (The Modern Student's Library); pp. 95, 96 (no date given).
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He held to a mechanical view of the world, including a mechanical view of human nature, the human body, and human society. The body is a machine. Human desires, including presumably man's loftiest aspirations, are nothing but motions of particles.
As already emphasized, Hobbes was one of the earliest philosophers to introduce the theory of the subjectivity of moral values. This implies that the world is not a moral order, although Hobbes did not express himself in those terms. He also draws from subjectivism the modern conclusion which affirms that morals are relative. Thus the whole paraphernalia of the scientific view of the world, as opposed to the religious view, are pre-eminently clear in Hobbes. And he drew these conclusions directly from the new science, which is one proof that that is their historical derivation.
Hobbes being one of the earliest exponents of the scientific view of the world is also one of the crudest. He does not see even the most obvious difficulties which beset his version of it. As time went on, these began to appear, so that later representatives of the dominant modern mentality, in trying to meet them, become increasingly more refined in their theories. But their theories are not in essence different. They are only more sophisticated.
David Hume (1711-177 6) was in one respect the opposite of Hobbes. While Hobbes was the crudest of naturalistic thinkers, Hume was perhaps the most subtle and acute, and probably the greatest. He was the master builder of the naturalistic view of the world—so far as its expression in the abstract form of phiilosophy is concerned. He is the father of all positivists down to the present day. One and all of them are in reality no more than dancing to his tune. His thought is the very quintescence of the dominant philosophical trends of the modern world. So that if we once understand it, we shall have in our hands the key to the understanding of the main positions of the later naturalistic thinkers.
I shall concentrate on only one of Hume's contributions to
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philosophy, which is, however, the most famous and characteristic—his theory of cause and effect. What, he asked, is meant when we say that one thing, C, is the cause of another thing, E? We say that a certain degree of cold causes water to turn to ice, and that a certain degree of heat causes it to turn to steam. We say that lightning causes thunder, or that bacteria cause diseases. Among all sorts of different kinds of phenomena there may exist this one kind of linkage or relation, which we call causation. What sort of a relation is it?
According to the traditional analysis of philosophers prior to Hume, to say that C is the cause of E means, or implies, two distinct things. First, it implies that whenever C happens E happens, or that any case of C is always followed by a case of E. Thus we believe not merely that today, at this particular place and time, a temperature of 212 degrees Fahrenheit will be followed by the boiling of this particular pot of water. We believe that whenever, other conditions being the same, water is raised to that temperature, it will boil. This is sometimes expressed by saying that the same causes always produce the same effects. This is a very rough statement. Someone might object that although striking a bell usually causes sound, it does not do so if the bell is in a vacuum, and that therefore the proposition that the same cause always produces the same effect is not true. What this means, however, is not that the proposition is false, but that it is very carelessly and imprecisely stated. It can be made accuurate by inserting the necessary qualifications. The most important of these is that, if the proposition is to be true, all the necessary conditions of the effect E must be included in the cause. Thus the cause of the sound is not only the vibration of the bell. The presence of air is also part of the cause, and when this is realized, the absence of sound in a vacuum ceases to be an exception to our rule that the same cause always produces the same effect. Even so the rule is extremely difficult to state with a precision which will make it quite watertight. To do this is a technical problem which we must leave on one side here. The general idea which the rule expresses is a familiar one, and is certainly implied by a belief in
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causation. It may be called regularity of succession. Hume's own phrase was "the constant conjunction' of cause and effect.
The second thing supposed, according to the analysis tradiitional before Hume, to be implied by saying that C is the cause of E is what Hume called a "necessary connection" between C and E. It is not merely that whenever C occurs, then, as a matter of fact, E happens to follow, as if the connection between them were merely a coincidence. There must be some necessary connnection between C and E, because if their conjunction were a mere coincidence, surely C might sometimes be followed by E and sometimes not. We must suppose therefore that there is something in C which makes E happen. We do not merely suppose that heat is followed by the melting of wax. We suppose that this must happen, and that this necessity is why it always happens. The cause is not only followed by the effect; it produces the effect. One thing exerts power over another, the sun, for example over the wax. The flame has a power to boil the water. "Influence" is another word we use to express the same thing. One thing influences another. Another word which we use in certain cases is "force." Thus if a moving billiard ball collides with another ball which is at rest, and the second ball begins thereupon to move, we do not say merely that when one ball hits the other at a certain angle and velocity, the second will always, as a matter of fact, move off at a certain angle and velocity (regular succession), but we say also that the first ball exerts a force upon the second. Thus what Hume means by belief in necessary connection is the belief that C is necessarily followed by E, and that the connection is not mere chance. Such words as "necessity," "power," "producing," "making," "influencing," "compelling," "force," such phrases as that the effect not only does, but must follow the cause, all carry essentially the same meaning.
The traditional theory of causation was that it meant both of these two things, regular succession and necessary connection. Hume's new analysis was intended to show, however, that allthough regular succession is a fact, necessary connection is a fiction. There is no such thing in the world. More strictly put,
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Hume's conclusion is that, as applied to nature, none of these words—"necessity," "power," "making,' "producing," etc. convey any idea to the mind; that they are all strictly speaking meaningless. The conception that many words and phrases used in language have no meaning, so characteristic of positivistic philosophies, makes with Hume its first appearance in philosophy. That various statements which men make are false had, of course, been often asserted. That they are often meaningless was a new idea, destined to play a great part in the subsequent history of thought.
The argument by means of which Hume sought to establish his conclusion about causation is based upon the theory of the origin of our ideas and knowledege which has come to be known as empiricism. John Locke had anticipated Hume in the statement of this theory, but Hume was the first to apply it with rigor. The theory is that all ideas whIch can exist in a mind have been prooceeded by, and are derived from, "impressions." An impression is the direct presentation of something to the mind, as for instance when we see a color. There are, according to Hume, two kinds of impressions, those of sensation—such as seeing colors, smelling smells, etc.—and those of what he called reflection, by which he meant what we should now call introspection—perceiving one's own feelmgs, thoughts, or other operations of the mind. All our ideas about the physical world are derived from impressions of sensation, while ideas about psychological facts are derived from impressions of reflection. It is only the impressions of sensation whIch are important to us in considering Hume's argument about causation.
Since every idea which has reference to the physical world must have had its origin in impressions of sensation—or more briefly, in sensations—you cannot have an idea unless you have previously had the sensations on which it is based. For instance, men born blind cannot have any idea of color. The idea of sound is for the same reason absent from the minds of those who have been born stone-deaf. Again, although bees perceive ultra-violet color, this color, which may be entirely different from any color
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which we can see, is to us wholly unimaginable because we have never had any sensation of it. In Hume s language, we cannot "frame the idea" of it.
It is true that we may have ideas of things which we have never seen or perceived with any of our senses, such as sea serpents, winged horses, or golden mountains. But it will be found that all such ideas are compounded out of ideas of sensations which we have had. We have seen wings and horses, so that we can combine them to form the idea of the winged horse. In this way even ideas of imaginary objects are derived from sensations, because they are built up out of materials which have been derived from sensations.
So far what has been stated is mere psychology—a generalization about the source of our ideas. But Hume proceeds to use it as a criterion for distinguishing meaningless words and phrases from those which have meaning. If we use a word to which there corresponds no idea in our minds, then this is the same as saying that the word has for us no meaning. For instance, color words can have no meaning for men born blind, though they will of course have meaning for those who can see. And if there are any words which are such that nobody has ever had any sensations from which the ideas for which they are supposed to stand have been derived, then there cannot in reality be any such ideas. In other words, these words must be entirely meaningless. There are, according to Hume, many such words and phrases. Necessary connection is one of them.
If it is suspected that a word is without meaning, the test to apply is: point out, or indicate in some way, the sensation or sensations from which the alleged meaning of the word has been derived. If you can do this, as the seeing man could if asked the meaning of the word "red"—he could point to red things—then your word will be admitted to have meaning. It. has passed the test. But if you can in no way, either directly or indirectly, indicate the sensations from which the idea supposed to be conveyed by your word has been derived, then it will follow that you have
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in reality no idea in your mind at all, or in other words that your word is meaningless.
It is true that this raises a psychological problem which may seem to present difficulties to the theory of empiricism. How can a man use language and believe that this language stands for ideas, at least to himself, when he has in fact no ideas in his mind at all? We must be content to remark that, somehow or other, it certainly is the case that there is such a thing as "meaningless verbiage," as anyone who has made a study of political speeches, not to mention philosophical treatises, must know.
Hume applies his empiricist theory of ideas to causation in the following way. Causation was supposed to imply two things: regular succession and necessary connection. Regular succession can be observed, which is another way of saying that the idea of it is derived from sensations. You see C, and then you see that it is followed by E. You see the flame under the kettle, and then you see the water boil. This gives you the idea of succession. You can also observe that this happens regularly, that whenever C happens it is followed by E. This gives you the idea of regular succession. Since you have pointed out the sensations from which this idea is derived, it has passed the empirical test, and may be admitted to be meaningful.
But now try the test on the other supposed component of causation, necessary connection. Is it not obvious, not only that no one ever has had a sensation of it, but that no one ever could have such a sensation? For all that can ever be observed is a succession or flow of events, one thing following another. Watch what happens when you put the kettle on the fire. You see the flame and the water. First you see the water still, and then you see it bubbling. You see the cause, the fire; and then you see the effect, the boiling. You may, of course, see intermediate stages, such as the "simmering" of the water. But this makes no differrence to the fact that all it would ever be possible to observe would be one thing following after another, that is to say, sequence, or succession. And as one event follows another, you could never
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observe the supposed necessary connection between them. You see the flame and then the boiling. But did you, or could you ever, observe the flame making the water boil? Did you, or could you ever, observe the "power" in the flame, or the "influence" which it is supposed to exert? You may think that your inability to have any sensation of necessary connection is due to the crudeness of your senses, and that science, with its sensitive instruments, will help you. But if you were to use an ordinary microoscope, or even an electron microscope, or even if you could see the individual electrons, it is obvious that all you could ever observe would be a succession of movements, events, or things. You could not observe any necessary connection between them.
Put the same thing in another way. You say not merely that the water does boil, but that it must boil when a flame is put under it. You say not only that, owing to gravitation, water does run always downhill, but that it must do so. But have you ever observed this "mustness," this necessity? All you can observe, or have a sensation of, is that water does boil, or does run downhill. In short, all you can observe is facts, not the necessity of the facts. This is the same as saying that it is impossible to indicate the sensations from which the supposed idea of necessary connection has been derived. The conclusion follows at once. There is no such idea. The phrase "necessary connection" is entirely meaningless. Therefore when we say that C causes E, all that can possibly be meant is that there is a regular succession of C being followed by E.
Hume's theory of causation has been the subject of furious controversy. It is not necessary for us to go into this because, for our present purposes, it does not matter to us whether Hume's theory is true or not. What we have to note is that it has passed, though not undisputed, into modern thought, and that it has been, and still is, tremendously influential. It has become, on the whole, the dominant view of causation as expressed in science. For instance, the practical disappearance of the concept of force from recent physics, if not directly due to the actual writings of Hume—most physicists have probably never read them—is at any rate
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due to the empiricist spirit of modern thought which found its philosophical expression in Hume. Physicists may of course still use the word "force," as we continue to use the expression "the rising of the sun"—for convenience. But it is thought to be no more than a useful fiction. Newton's theory of gravitation uses the concept of gravitational force. But Einstein's theory dispenses with it altogether.
What, it will be asked, has Hume's theory of causation to do with the main themes of this book, or with what I have called the scientific view of the world? How does it in any way conflict with the religious view? There is in it no mention of God, purpose, freedom, or morals. But this first appearance is superficial and deceptive. We have to look below the surface. What kind of a universe, we must ask, is implied by Hume's analysis of the conception of cause and effect?
It follows from the denial of necessary connection that, allthough in our past experience one thing C has invariably been followed by this other thing E, and although, therefore, when we observe C again, we naturally expect E to follow, there is in fact absolutely no reason why it must follow or why we should expect it. When the kettle is put on the fire it always boils. At least this has always happened in the past. But how do I know that the water will boil the next time I put the kettle on the fire? According to Hume's own explicit and repeated statements there are no rational grounds whatever for my expectation. The expectations are founded, according to Hume, on nothing but habit or the association of ideas. It is a psychological fact that if two things. have been constantly associated in my experience, then they become linked together in my mind in such a manner that the apppearance of one always causes me to expect the appearance of the other. Since I have always in the past observed 'kettle-on-fire' to be followed by 'boiling-of-water', the ideas of these two things have become so firmly associated that when I observe a new instance of the first I cannot help confidently expecting that it will be followed by an instance of the second. But the passage of my mind from C to E is a psychological, not a logical, transi-
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tion. Hence there is no logical reason why I should expect C to be followed by E. For since there is no necessary connection beetween heat and boiling there is no reason why the sequence should be repeated. If there were something in the heat which makes the water boil, then I could know that the water will necessarily boil. But there is no such necessity. It is therefore merely luck, chance, or good fortune that the world so far has not dissappointed our expectations, and that things have always happpened in a regular and orderly fashion. For what is true of the fire and the boiling is of course equally true of every other causal connection of events. We have no more reason to believe that water will always freeze in the cold than that it will always boil under the influence of heat. We have no good logical reason to expect any orderly sequences in nature at all. The orderly universe might tomorrow become a chaos.
This is the source of the philosophical problem whIch I mentioned earlier: how do we know that the sun will rise tomorrow? We believe it because we assume that the causes which have so far operated to bring about the daily rising of the sun will continue to bring about the same effect in the future. We assume, in other words, that what we call the laws of nature, which means the regular sequences of causes and effects, will operate in the future as they have in the past. This assumption, we hope, will turn out to be true. But, if Hume is right, there is no rational ground for It. Therefore it cannot be "proved" that the sun will rise tomorrow. Nor can any other prediction about the future be proved. When the kettle was placed on the fire yesterday, it boiled. But for all I know, when I put it on the fire this afternoon, it may freeze, or fly away to the North Pole, or turn into a watermelon.
These implications of Hume's philosophy, which he himself clearly perceived and insisted upon, amount to saying—though he does not himself put it in this way—that there is no reason why anything happens as it does and that the universe is totally irrational and senseless in its proceedings. We can ask what happens, but to ask for a reason why it happens is to ask a meaningless question. Heat does as a matter of fact boil water, but there is no reason why it should, for it might just as well freeze it. To ask for a reason why will always involve somewhere the idea of a necesssary connection between events. And there is no such thing in the universe. Hence there being no reason for anything; all we can say is that what happens happens. It just is so, and that is the. end of the matter. Everything is just a brute fact. We live in a brute fact universe.
This has given rise to what is called the descriptive theory of science. Science can never, on this view, do anything except describe what occurs. It can never explain anything in the sense of giving a reason why it occurs. It is true that we talk, and scientists themselves talk, of "scientific explanations." But these turn out to be only generalized descriptions. For instance, suppose a savage brought from tropical Africa to America, having never seen ice, is astonished to see a pond freeze in the winter. He asks why the water turned solid. It is explained to him that this is an example of the "law" that water at sea level freezes at 32 degrees. Fahrenheit. The law is the explanation. But all it tells anyone is that whenever the temperature falls to 32 degrees, water turns solid. This, however, is only to state what always happens, not to give any reason why it happens. But this, it may be said, is very crude science. For science does not stop at that elementary level. It goes on to explain why water always freezes at 32 degrees. The explanation will be in terms of molecules, atoms, or perhaps, if it is carried far enough, electrons and protons. The molecules, in the cold, move more slowly, perhaps. But this still only states what always happens without giving any reasons. It tells us that when it gets cold, the molecules always move more slowly. It is obvious that, however far science proceeds, its explanations can never consist in anything but descriptions of what happens, and can never tell us why. It cannot give "reasons" because—on the Humian view—there are none, and the very demand for them is without any meaning.
This then, the vision of a world without purpose, sense, or
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reason, is the inner substance of Hume's philosophy. That philosophy plainly expresses, in its own fashion, he scientific view of the world, the modern Weltanschauung derived from science.
The train of thought just described is not, as a matter of fact, strictly logical. For there is an ambiguity in the word "reason." Sometimes it means purpose, sometimes it means cause. Thus we say that the reason why we caught a cold was that we were exposed to a draught. The draught was, in fact, the cause of the cold, and it is plain, therefore, that if we give it as the reason why we caught a cold, we are using the word "reason" as equivalent to the word "cause." But we might inquire why, or for what reason, a man sat in a draught. In that case we are probably askking what his purpose was, and if so we should think he had answered our question if he said: "I sat in the draught in order to get cool." Here plainly the word "reason" has been used as equivalent to the word "purpose."
If now we say that, according to Hume's philosophy the world is senseless and meaningless because there is, according to that philosophy, no reason why water should freeze when it does, rather than boil, we are probably using the word "reason" as equivalent to "purpose." By an irrational, senseless, and meaningless world, we probably mean a purposeless world. But that the world is purposeless does not strictly speaking follow from Hume's philosophy. What he shows is that there is no necessary connection between events. But necessary connection is not the same as purpose. Suppose we believe that all events are guided by God's purposes. This is not refuted by anything which Hume says. For he does not show that there is no such thing as purpose in events, but only that there is no such thing as necessary connection.
But this is simply an example of what has been so often illustrated in this book-that it is not logical, but psychological transitions, which govern men's minds. A brute fact world, a world in which anything might happen, in which water might tomorrow begin to run uphill, in which all the laws of nature might be turned upside down, is not necessarily irrational in the sense of being without purpose. For perhaps it is owing to the purposes
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of God that the world as a matter of fact does not become chaotic but follows regular laws. But the fact remains that Hume's world, in which any chaotic absurdity could happen at any time, seems to men to be a senseless and irrational world, and that they naturally identify the idea of such a world with the idea of a world which is senseless and meaningless in the sense of having no purpose. There cannot be any doubt that in this way Hume's world-picture is, or suggests, the typical world-picture of the modern mind.
Consider the impact of these thoughts on an age-old question—the famous "problem of evil." We ask why there is evil in the world. Why do the wicked prosper while the good are oppressed? Why are men born with hideous deformities which they have done nothing to deserve? Why are innocent children cut off, subjected perhaps to the miseries of cancer or inherited syphilis and then to early death? How do we explain these injustices? Why are they permitted?
But what does the word "why" mean here? What is it that we want to know about evil when we ask the "why" of it? Let us take what is no doubt a trivial example. A man has a toothache which, we will suppose, is entirely undeserved. Evil is sometimes classified as either moral or physical. Pain is a physical evil. And in view of the dreadful agonies which men suffer in the world this toothache is of course nothing. But this trivial example illustrates the principles of the problem of evil just as well as would all the miseries caused by a world war. The amount of the evil has nothing to do with the problem why there should be any evil at all. Why then is there this toothache?
But we put the same question again: what does this "why'" mean? What is it that we want to know about the toothache when we ask why? Do we want to know the cause of the toothache? The dentist, no doubt, can explain that quite well. It is caused by an abscess, which was caused by bacteria, and so on back into the past. Is this what we wanted to know? We can apply the same thought to the human agonies suffered in a war. The causes of a war are much more difficult to discover than the causes of the
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toothache. But still there must be causes, and they must be theoretically discoverable. Suppose that we did discover all of them. Suppose we discovered all the causes of all the evil, physical and moral, which has ever existed in the world. Should we then feel that the problem of evil had been solved?
No. Because when we ask the "why" of evil we are not asking for its causes. What then are we asking for? Plainly what troubles us is the apparent injustice of most of the world's pain and evil. Admitting for the sake of argument that some men may sometimes deserve what they get, it still remains a fact that a vast amount of the sufferings of men, not to mention those of animals, are quite undeserved. What we want to know is how this injustice is to be explained. But this question assumes that somehow, in spite of all appearances to the contrary, the world-process must in the end work justice. Thus the problem of evil is based upon the assumption that the world is a moral order. But this is just what the modern world-view, which is embodied in the philosophy of Hume, denies. Hence the problem of evil, in the setting of the modern Weltanschauung, has no meaning at all. It is, as a philosophical problem, simply out of date. Such a question as why there is evil in the world can only be asked by a medieval mind. There is, in reality, no such question for the modern naturalistically-minded man. And it is accordingly treated as a pseudo-problem by the positivists who are the modern followers of Hume.
Another way of putting the same thing is to say that the probblem of evil assumes the existence of a world-purpose. What, we are really asking, is the purpose of suffering? It seems purposeeless. Our question of the why of evil assumes the view that the world has a purpose, and what we want to know is how suffering fits into and advances this purpose. The modern view is that suffering has no purpose because nothing that happens has any purpose. The world is run by causes, not by purposes.
The other philosophers on our list, Comte, Vaihinger, and the logical positivists may be dealt with in a short space because they
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are all spiritual descendants of Hume, and however their technical doctrines may differ among themselves, or from Hume, they are all at bottom expressing the same vision of the world as Hume expressed.
According to Auguste Comte (1798-1857) human knowledge necessarily passes through three stages, which he calls the theoological, the metaphysical, and the positive. In the theological stage men explain events by gods or spirits. In the metaphysical stage they explain them by "abstract forces, personified abstractions. The essence of a metaphysical idea, in Comte's opinion, is that it is the idea of something which cannot be observed. For instance, if we say that two bodies "attract" one another—as Newton did—one can observe their motion towards one another but one cannot observe the supposed attractive force. Comte agrees with Hume that a cause, in the sense of a force or necesssary connection, is in principle unobservable. He calls it therefore a "metaphysical notion." Regularity of succession is the "positive" notion because it can be observed.
In the third or positive stage of knowledge all explanation is gIven m terms of what can be observed, and what is in principle unobservable is dismissed as metaphysical. The positive stage is the stage of science which, when fully attained, abolishes both metaphysics and theology. In the golden age of the future which the triumph of science is to usher in, nothing will be considered knowledge unless it is science. All education is to be scientific. And what science means is nothing except the establishment of natural laws, that is to say, regular sequences of events. If we know that whenever C happens, E happens, we know everything that there is to know. Everything else is either metaphysics or superstition. No science, and therefore no knowledge, can tell us why anything happens (in any other sense than giving its cause), because there is no why.
All this, plainly enough, carries the same world-picture as did the philosophy of Hume, from whom in fact it is obviously derived.
When Comte, or the present-day positivists, condemn as meta-
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physical the idea of anything which is not observable, they are merely repeating in other language Hume's empiricist doctrine that all ideas are derived from impressions and that there can be no idea without its antecedent impression. For to observe someething is exactly what Hume meant by "having an impression" of it. The idea of red, according to Hume, is derived from the prior sense-impression of red, i.e., from having observed something red. Hence the sentence, "There is no idea of that of which we have had no impression," means the same as the sentence, "There is no idea of that which is unobservable, and any such alleged idea is metaphysical and meaningless." This makes clear the relation of Hume to positivism, whether that of Comte or that of the logical positivists of the present day.
Vaihinger is a transitional and no doubt not very important figure in the history of philosophy. But he illustrates the tendencies of the modern age. His contribution to philosophy consisted in his theory of fictions which he embodied in a book called The Philosophy of As If, published in 1911. Its essential doctrine is that only what is observed is real and that everything else, which we may conceive or imagine, is merely a fiction. Fictions may be either useful or useless. The man in the moon is a useless fiction. But "energy" is a useful fiction because it helps us to tie together our observations in an orderly system so that the mind can predict and control its experiences and so guide the organism through life successfully. Fictions are useful if the world behaves as if they were true, useless if this is not the case. For instance, neither the moon nor anything else in the world behaves as if there were a man in the moon. Hence the idea of such a man does not help us to predict phenomena, and is useless. But it is otherwise with the idea of the ether of space (which was still a part of physics in Vaihinger's time). The ether does not exist, for it cannot be observed. But light and heat, travelling from the sun to the earth, behave as if they were waves of such an ether. The ether is therefore a useful fiction, since it enables us to foresee the phenomena of light and heat.
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Both our common-sense knowledge and our science are shot through and through with fictions. The sequence, visible lightning—audible thunder is a fact but the electricity which is said to explain it is a fiction. For the electricity, apart from its sensible manifestations in sounds, lights, etc.—which are commonly called its "effects"—could never conceivably be observed. God is a fiction which may be useful to some people if it enables them to fight the battle of life more courageously. Free will and moral responsibility are fictions, but they are useful, and even necesssary, because without them society would be impossible. We must punish criminals, and in general hold people responsible for their actions, although these are, in fact, completely determined beforehand by their causes. For this reason we invent the fiction of free will. Atoms are fictions because they cannot be seen. But they are useful because in terms of them we can state chemical laws which make it possible to predict the future behavior of bodies. Even mathematics is full of useful fictions. Points which have no magnitude, lines which have no breadth, are obvious fictions. And geometers treat circles as if they were regular polygons with an infinite number of straight sides. This is plainly not true, but it enables the geometer to solve problems about circles.
Vaihinger calls himself a "critical positivist." He writes:
From the standpoint of critical positivism, then, there is no Absolute, no thing-in-itself, no subject, no object. All that remains is sensations, which exist, and are given, and out of which the whole subjective world is constructed with its division into physical and psychical complexes. Critical positivism asserts that any other, any further claim is fictional, subjective, and unsubstantiated. For it only the observed sequence and cooexistence of phenomena exist, and upon these alone it takes its stand. Any explanation going beyond this can only do so . . . through fictions.2
It is plain that Vaihinger's philosophy is derived from the great Humian doctrine that we can have no ideas except those which are based on impressions, and that it embodies in its nakedest
2 The Philosophy of 'As If,' trans. C. K. Ogden (London: Kegan, Paul, Trench, Trubner & Co., 1924), Part I, chapter 18.
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form the scientific view of the world as opposed to the religious view. For what is his world but a senseless drift of sensations which follow each other 'With endless and meaningless iteration? The "real" world is no more than what one may suppose some low-grade organism, a crocodile perhaps, to perceive; merely sensations of hot, cold, color, light, sound, hard, soft, pleasant or unpleasant smells and tastes, succeeding one another forever. In these sensations there are no doubt "regular sequences," that is, repetitions of the same following the same, which we dignify by the name "laws of nature." But how does that make the sensations any more sensible? Any suggestion that there is in all this any plan or purpose, or that the world so conceived is a moral order, must plainly be, on Vaihinger's principles, no more than a fiction.
The most popular school of philosophy in our own day is that of the logical positivists. In many technical problems of philosophy they have done original and useful work. In its mode of statement, and in the arguments which they use to support it, their version of positivism is quite different from that of Comte. They would certainly wish their philosophy to be distinguished from his, and they cannot be represented as merely his disciples. Nevertheless the spirit of the two philosophies is the same; and they both imply the same Weltanschauung.
Their original slogan was "the meaning of a statement is identical with its method of verification." This has been modified by a number of technical qualifications, but the principle remains the same in substance. It implies that a statement for which there is no possible method of verification is meaningless. And verification means either direct observation by the senses or indirect inferences from such observations. Thus the surface of the moon which is turned towards the earth can be directly observed, and many statements made about it can be verified by naked sight or by telescopes. But if an astronomer makes a statement about the other side of the moon, which no eye has ever seen, this cannot of course be directly verified, but it may be possible validly to infer it from facts which can be observed. Hence "There are
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mountains on the back of the moon," whether true or false, is not meaningless, since its truth or falsity might follow from observations which can be made. But if we say, "Energy is something which could never possibly be perceived, but which manifests itself in heat, light, electrical phenomena, motion, etc.," this will be meaningless if it is supposed to refer to some mysterious entity which has an existence of its own distinct from the heat, light, or other observable phenomena in which it manifests itself. For nothing but the heat, light, etc., could ever be observed, nor for technical reasons of logic is it possible validly to infer its existence from them. The energy just is its manifestations. And all that a statement made by a scientist about an energy which underlies heat and motion can mean is that there is a certain mathematically calculable equivalence between, say, the motion of a body and the heat which replaces it when the body is brought to a stop by friction. The scientist may quite legitimately use the word "energy," but this is all that his statements about it can mean. All that science can do, or aims to do, is to note the regular sequences of observed phenomena, including the equivalences referred to. Likewise the scientist may use such an expression as "attractive force" in gravitation, but this is only a handy way of talking about the observed tendencies of bodies to move towards one another according to certain mathematical formulas. For only the motion can be observed, not the force.
It must not be supposed that this view of scientific conceptions is necessarily unacceptable to the scientists. On the contrary, many scientists are themselves positivists, and not only accept it, but assert it with vigor. But it is not really a scientific question at all. It is a philosophical question. So long as the scientist can pursue his studies of atoms and electrons in his own way, and can by means of them state laws which will enable him to predict the future, it is of no importance to him whether they are fictions or solid realities.
One of the great ideas of the logical positivists—in which they agree with Comte—is that all metaphysical statements are meaningless. Their philosophical opponents are fond of saying that positivism itself implies, or rests upon, an unconscious metaaphysics. Whether this is true or not depends upon what meaning one gives to the word "metaphysics." If a metaphysical idea is defined as one which refers to some hidden, forever unobservable "ultimate" reality, then it is probably true that positivism neither has nor implies any metaphysics. But if the term means only a general view of the nature of the world, a Weltanschauung, then positivism does imply a metaphysics, whether positivists are aware of the fact or not, whether they deny it or not. They must have a metaphysics in this sense because every thinking human being has one. And the nature of their view of the world is not hard to discern. It is the same as Hume's and Vaihinger's. The world is nothing but a stream of events. It is nonsense to talk of any purpose, order, or meaning in it. It is the function of science and mathematics, which alone are knowledge, to predict from one set of senseless events what the succeeding set of senseless events will be.
That the view of the world which is the inner meaning of currrent positivism is simply the modern Weltanschauung is made abundantly clear by the views of positivists on ethics and the theory of value. Consider the ethical statement, "Murder is wrong." How, asks the positivist, can you verify this by any conceivable observation? If a murder has been committed, there will have been a lot of facts about it which could have been observed if anyone were present. He might have seen the murderer raise the gun, point it, pull the trigger. He might have heard the explosion. He might have seen the victim fall to the ground and the blood ooze from his chest. But he could not have observed the wrongness of the action. Do you see, hear, or smell, wrongness? It is plainly unobservable. It cannot be verified either directly or indirectly. Therefore the sentence, "Murder is wrong," is meaningless.
Why then do people say such things? Because although they are meaningless in the sense that they do not state facts and cannot therefore be either true or false, yet they do express the feelings of those who utter them. To quote a prominent British positivist, Professor A. J. Ayer: "If I say to someone 'You acted wrongly in stealing that money, I am not stating anything more than if I had simply said 'You stole that money.' In adding that this action is wrong I am not making any further statement about it. I am simply evincing my moral disapproval of it. It is as if I had said 'You stole that money' in a peculiar tone of horror, or written it with the addition of some special exclamation marks. The tone, or the exclamation marks, adds nothing to the literal meaning of the sentence. It merely serves to show that the expression of it is attended by certain feelings in the speaker."[3]
The point is that the moral utterance expresses an emotion, but does not state or deny any fact. Emotions simply exist. They are not true or false, nor can any words by which they are expressed be true or false. Factual statements, however, are always either true or false. An assertion of wrongness is therefore like saying "Ah!" This ejaculation may express my feeling of surprise, but to say "Ah!" is not to say anything which is either true or false. It does not state any fact. In the peculiar jargon of the posiitivists a sentence is said to have meaning only if it can be true or false. It is in this sense that, according to them, both "Ah!" and "Murder is wrong" are meaningless locutions. They do not intend to deny that they express feelings or attitudes or emotions which are really present in the speaker. Hence the statement that "murder is wrong" is meaningless, sounds more cynical and immoral than it actually is. For it uses the word "meaningless" in a technical sense. There is no reason to suppose that positivists approve of murder or are trying to condone it. There is no reason to doubt that they themselves approve and disapprove of most of the same things as other people, that they are themselves capable of high moral indignation and of high moral ideals.
This is not the point. The point is that this theory of morals is a subjectivistic one. And subjectivism implies, as we have seen, that the world is not a moral order. Professor Ayer has his own
3 From Language, Truth and Logic (2nd ed.: London: Victor Gollancz, 1948; New York, Dover Publications), chapter VI, by Ayer, reprinted by permission of Dover Publications, Inc.
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definition of subjectivism, which differs from mine. According to his definition his view is not subjectivistic. That, however, is merely a matter of words. The positivistic view holds that moral utterances do not state facts, but merely express emotions, feellings, or attitudes. Morals therefore are dependent on human feelings, emotions or other psychological states, and this makes the theory subjectivistic in terms of the definition adopted in this book. Whatever word we use, the theory plainly implies that, since morals are only the expression of human feelings, they have no basis in the world outside the human mind. And that the world is not a moral order is one of the fixed points of the peculiar modern world-picture.
Positivists have made important contributions in the technical fields of logic, logical analysis, and semantics. It is these technical contributions which they themselves emphasize and care about. It is doubtful whether they would admit that these technical theories imply, or rest upon, the general view of the world which I have ascribed to them, or any general view of it. In such matters they are as a rule wholly uninterested. They talk about anything rather than the nature of the world. They talk about verbal analysis, logical rules, the nature of mathematics, the different uses of symbols, the meanings of the word "meaning." They discuss how we know that 2 + 2 = 4, or that all crows are black. They dislike all world-views as savoring of metaphysics, to abjure which is a part of their creed. They may well be unconscious that their philosophy expresses any world-view. But the Weltanschauung of an age grips the men of the age and pulls the strings from behind the scenes. The little philosophers dance to its tune whether they know it or not.
The philosophers of the modern period seem all to be very different from one another. Philosophy is indeed often reproached for being nothing but a bedlam of conflicting opinions in which no order or pattern can be found. Descartes advocated dualism, the view that matter and mind are two wholly different kinds of thing. Hobbes taught materialism. Hume gave us an analysis of
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causation, Comte a historical theory of the different stages of culture, Vaihinger a theory of fictions, the logical positivists a theory of the meanings of sentences. Yet there is a pattern and an order to be found in all this if we look below the surface techhnicalities. There is this single world-view expressed by them all, each in his own way, the naturalistic or scientific world-view.
But the picture of modern philosophy which has been drawn in this chapter is one-sided. We have traced, from Descartes to the present day, only the dominant tendencies of the modern mind as they express themselves in philosophy. But the dominant trend has not been the only trend. There have been powerful forces working against it, and these forces too were certain to express themselves in philosophy, as also in art and literature. That there is no purpose in anything, that human life like everything else is futile and meaningless, that the world and all that is in it including human beings are governed by blind material forces, that there is no goodness, no beauty, nor any other kind of value in the universe save that only which men themselves have invented, that we are all carried along helplessly on pre-determined paths, that we have no choice and no control of our own destinies—this is a dismal set of doctrines. Protests and reactions against it were bound to make their appearance—among philosophers as well as among poets, artists, musicians, and scientists. The human spirit rebels against such conclusions. Rebellion will take the form of a return to a more religious view of the world. It cannot be indeed merely a revival of the medieval world-picture. That can never return. The religious spirit will express itself in forms suitable to the age in which it appears.
Religious men will be apt to say that revolts in favor of the religious view of the world are due to the fact that religion, in some form or other, is a divine truth which cannot therefore be suppressed by science or by anything else. They will ascribe to this divine truth an inherent power to triumph over all enemies. Skeptics, on the other hand, are likely to ascribe the protests and reactions against the scientific view of the world to wishful thinkking. Men refuse to accept a truth which they do not like. They
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prefer to believe in comforting dreams and illusions. We have not yet reached a stage at which we can consider which of these two views is true. We are concerned at present only to record what has happened, and how the tensions of the modern mmd have been produced. And we shall continue this story in the next chapter, giving there the missing half of the picture.
