This paper is a revised form of a Mahlon Powell Lecture delivered at the University of Indiana in 1961. Published in Charles J. Bontempo and S. Jack Odell, ed. The Owl of Minerva: Philosophers on Philosophy (1975).


Brand Blanshard


Philosophy is best understood, I think, as part of an older and wider enterprise, the enterprise of understanding the world. We may well look first at this understanding in the large. I shall ask, to begin with, what is its goal, then what are its chief stages, then what are the ways in which philosophy enters into it.

The enterprise, we have just said, is that of understanding the world. What do we mean by understanding -- understanding anything at all? We mean, I suppose, explaining it to ourselves. Very well; what does explaining anything mean? We stumble upon some fact or event that is unintelligible to us; what would make it intelligible? The first step in the answer is, seeing it as an instance of some rule. You suffer some evening from an excruciating headache and despondently wonder why. You remember that you just ate two large pieces of chocolate cake and that you are allergic to chocolate; the headache seems then to be explained. It is no longer a mere demonic visitor intruding on you from nowhere; you have domesticated it, assimilated it to your knowledge, by bringing it under a known rule.

What sort of rules are these that serve to render facts intelligible?

They are always rules of connection, rules relating the fact to be explained to something else. You explain the headache by bringing it under a law relating it causally to something else. In like manner, you explain the fact that a figure on the board has angles equal to two right angles by relating it logically to something else; by pointing out that it is a triangle, and that it belongs to the triangles as such to have this property.

Such bringing of a case under a rule explains admirably so far as it goes. But suppose someone asks for a further explanation. When you explain your headache by reference to the chocolate or the angle sum of the figure by referring to its triangularity, he says: "Yes, yes, I know this, but what I don't understand is why the rule itself holds. How do you explain that?" We can only give the same answer as before. To explain a rule is to connect it with some other rule from which it follows, just as to explain a fact or event is to connect it with some other fact or event. When you can so connect it, you can explain it; when you cannot, you can't. You can explain why a triangle should have angles equal to a straight line because you can show that this must be true if certain other propositions are true that you normally accept without question. Can you show similarly that the rule about chocolate producing headaches follows from some further rule? No doubt an expert allergist could. He would show that in trying to assimilate the protein molecules of the chocolate, certain of your body cells break down; and the rule that eating chocolate produces a headache follows from the further and more precise rule that a certain kind of cell deterioration produces a certain kind of headache. But then why should this hold? Why should a change in body cells produce a conscious ache? All explanations so far offered here run into a stone wall. We can see that certain changes in the body are in fact followed by changes in consciousness; we have not the slightest idea why.

At this point two courses are open to one who is trying to explain his world. He has come -- or if he has not, he soon will -- to a generalization that he cannot now explain by bringing it under anything more general. Is he to continue in his attempt or not? The likelihood of his doing so may well depend on what he takes the ideal of explanation to be. Present-day empiricists are quite content to end their inquiries with rules or laws that are merely statements of general conjunction. Certain changes in the body are always accompanied by certain changes in consciousness. Why? That is a foolish question. If they are always in fact so connected, what more could a sensible person ask? One explains a falling snowflake or raindrop or meteor by bringing it under the law of gravitation, and if that law has been made precise, if one can show that the earth and the snowflake are so connected that each pulls the other with a force varying directly with its mass and inversely with the square of its distance, what more could one want? One might, to be sure, find some still wider generalization from which the law of gravitation itself followed; this was a leading interest of Einstein's toward the end of his life, and it made sense. But if further explanation means more than this, the empiricist holds, it is a will-o'-the-wisp. Every explanation of fact must come sooner or later to a dead end. It must halt somewhere with a generalization that is a pure statement of de facto togetherness, itself opaque to reason.

But there is another ideal of explanation open to us, that of the rationalists, of whom I am one. They hold that when you end with any law whatever that is a mere statement of conjunction, your explanation is incomplete and you are bound to try at least to go beyond it. What leads them to say this? It is their sense of the goal that understanding is seeking, of what would bring the attempt to explain finally to rest. When you ask the question "Why?" you are seeking an answer of some kind; but of what kind? We can see with regard to some answers that we can raise the same question again, of others that we cannot because we have already reached the end of the line. Suppose you remark that two straight lines do not enclose a space, or that whatever is colored is extended, or that a thing cannot at once have a property and not have it, and suppose now some bright skeptic asks you why. Could you give him an answer? I do not think you could, not because there is an answer that you don't know, but because anyone who understood your remark would know the answer already and would be asking a silly question. When you have a law that connects things by a self-evident necessity, the question "Why?" has no point, for the kind of insight you have is just the kind you are asking for. If you see that, being what it is, A must be B, the further question "Why?" is meaningless.

What understanding is seeking, then, what would bring the search to rest, is seen necessity. Where it is present, we have what we wanted; where it is absent, we have not yet fully understood.

Now a rationalist is a person who assumes that behind every is there is a must, that if snow is white or fire burns or John has a cold, the question "Why?" has an answer, and that this answer would disclose a necessity. You may protest: "Can you prove this? Do you really think that because we are seeking necessity, it must be there to be found, that things must be intelligible because it would be so satisfactory to us if they were?" The answer, of course, is "No." The philosopher who takes something to be true because he wants it to be true betrays his calling. But unless the philosopher could assume that there was some answer to his questions, he would have no motive for pressing them. For the critical rationalist the intelligibility of things is neither a necessary conclusion nor an arbitrary assumption, but a postulate, that is, a proposition which for practical purposes he must assume and which experience progressively confirms, but which is incapable of present proof.

Thus the rationalist is, if you will, a man of faith. His faith is that there is to be found in the universe the kind of intelligibility that would satisfy his intellect, that there is a coincidence between reality and his intellectual ideal, that at every point there is an answer to his question "Why?" This faith is the mainspring of his endeavor. He is ready to discard it if he has to, but not until he has to; and he will regard an apparent defeat as only a temporary setback if he can. After all, if there is no answer, why seek it? One may say indeed with George Saintsbury that "the end of all things is bafflement, but it is good not to be baffled too soon." But if we expect nature at any moment to set a roadblock to our reason, we shall almost surely be baffled too soon.

My own faith as a rationalist goes further still. If you ask me why snow is white or why you are reading these lines, I am inclined, as I admitted, to say that there is an intelligible, that is, a necessary, answer to the question, whether we know it or not. Some people would agree with this but would be reluctant to take the next long step with the rationalist. That step is to say that this necessity holds not only between the event of your reading these lines, for example, and some event just before it, but between your so doing and all other events. I am inclined to think that if you had not at this moment been reading these lines, the Mona Lisa would not be hanging in the Louvre. The argument is in principle this. Start with the supposition that a present event had not happened, and ask what it commits you to. If you deny the consequent, you must deny the antecedent, which means that if you deny the present event, you must deny the whole succession of necessary causes which led to this event, no matter how long the string. Very well, take some remote bead on that string and deny it; what then? All the events that follow from it as necessary effects will presumably have been different, and since the causal lines diverge in many directions, much of the present world will inevitably have been different.

Make the argument concrete. Is there any remote event in history to which your reading these lines can be traced back? There are indefinitely many; I shall name just one. In the year 490 B.C. a council of war was held on a hill overlooking the Greek coast. The council consisted of eleven commanders of a small Greek force, who were considering what to do about a huge Persian army that was disembarking below them. They knew the intention of that army. It was to wipe out Athens. The presiding general, Callimachus, took the vote of the council on whether they should give battle or not. The vote was five to five, and it fell to him to cast the deciding ballot. He voted for immediate attack and shortly paid for it with his life on the plain of Marathon, not realizing that by his vote he had decided the fate of the Western world. The historian Sir Edward Creasy argues convincingly that if Athens had gone under, so would Greece; and that with the fall of Greece, the science, philosophy, and art of the West would all have been smothered in their cradle. Plato, Archimedes, Leonardo would probably never have been heard of.

In short, deny that you are reading these lines, follow the stream of causation backward, then follow its diverging lines forward again, and you cannot with any confidence say that Leonardo would have lived or painted at all, let alone that his masterpiece would be hanging in the Louvre. Indeed, I suspect that every event in the universe is thus connected, directly or indirectly, with every other. And since in my view, which must here remain unargued, causality involves necessity, the universe must be assumed to be both a causal and an intelligible system in which every part is necessarily linked to every other. The complete explanation of anything would in the end involve everything. The world is a whole in which there are no accidents and no loose ends.


Now the career of reason, of which philosophy is one part, is a slow persistent climb toward the vision of that whole. On its way it passes through four levels -- those of infancy, common sense, science, and philosophy. We shall see more clearly the part of philosophy in this enterprise if we briefly retrace our steps through the earlier levels.

For each of us the adventure of the mind begins in a swamp so far below where we now stand that we cannot see it or clearly imagine it. We begin with sensation, "a booming, buzzing confusion" of sensations, signifying nothing. What takes us out of the primitive swamp is the formation of solid little islands in the swamp, nodules of qualities that stick together and behave in settled ways. It is a triumph of tender reason when the child can grasp one stable cluster of qualities as a bottle and another as a rattle. He is breaking through to the level of common sense where we chiefly live.

By the commonsense world I mean the world of things and persons. The transition into this world the child makes in those years that Bertrand Russell called the most decisive in one's life, the years from one to two. About this most familiar of all realms I want to make two observations, first that it is an intellectual construction, and second that it is no permanent home.

First, it is a construction. Things as a whole are never given in sensation; when we perceive a red ball, what we see must be pieced out by interpretation based on our past experience of its having another side. Common sense believes that some of the things I see moving about are persons with feelings and ideas like my own, though this is a metaphysical flight that it can never directly verify. Further, it believes that when you and I look at the ball, we are seeing the same thing -- a daring and highly dubious theory. Indeed the head of the plain man is full of theories about men, women, foreigners, artists, and communists, and his religious beliefs are brimming over with metaphysics.

The second remark to be made is that much of this theory is bad theory. The plain man's theory of knowledge, his religious beliefs, and his generalizations about things and people, recorded often in his proverbs, are riddled with inconsistencies. "Be not pennywise," he says, and adds, "Take care of the pence and the pounds will take care of themselves." He accepts both quite serenely.

In the commonsense world, then, reason can find no permanent home or halting place. It must move forward into science. This advance is not an abrupt leap into a new order or dimension. Science, as T. H. Huxley said, is common sense refined and organized. The commonsense world is a theoretical construction that has been built up by roughly fifty thousand centuries of trial and error, and much of it comes as a legacy acquired without effort. The scientific order is a superstructure most of which has been built in the last three centuries. But the two structures are continuous, and the newly built upper story will perhaps be occupied by our descendants as effortlessly as we have acquired the lower ones. To pass from the lower to the higher, however, requires the ascent of two flights of stairs, the first of which takes us to a new level of abstraction and the second to a new level of exactness.

First, abstraction.. The physicist as a man may have much interest in Jane Doe as a person, but as a scientist he has little or none. He breaks her up into a set of properties and studies these singly. In point of mass, she is indiscriminable from a sack of potatoes, and if dropped from the leaning tower, she would accelerate at the same rate. For science, the interest held by a law is proportioned to its generality, and the more general it is, the more abstract are the qualities that are related by its laws.

Secondly, exactness. The scientist is never satisfied until the characters he correlates are measured and their variations can be stated as functions of each other. Anyone may notice an apple falling from a tree or the increasing pressure in the pot when it boils, but it takes a Newton with his law of the inverse squares to describe exactly what the apple is doing, and Boyle with his inverse variation of volume and pressure to describe exactly what is happening in the kettle.


The passage from common sense to science is not a passage to a new kind of thinking, but a refining of processes already at work. So is the passage from science to philosophy. It is a grave mistake to set up science and philosophy as rivals of each other; they are continuous with each other. A philosophy that ignores science will probably build castles in the air, and a science that ignores philosophy will be dogmatic or myopic or both. Philosophy, as I view it, is so bound up with science, so integral a part of the same enterprise, that I have here insisted on winding into it through the avenue of science.

Is there any need for going further? Many people in these days say no. "What is knowledge is science," Russell remarked, "and what is not science is not knowledge." It used to be said that to the English had been given the realm of the sea, to the French the domain of the land, and to the Germans the kingdom of the air; this meant of course the stratosphere, where philosophers are supposed to live, and indeed have been living ever since Thales wandered abroad with his head in the clouds and fell into a well. With these critics I must confess that I have much sympathy. The philosopher who pontificates about being and nonbeing in a prose that follows Dr. Johnson's alleged rule of never using a word of one syllable if he could find one of six seems to me rather worse than bore. He is supposed to be a specialist in clear thinking and therefore clear speaking, and if he appears in public in a state of logical and linguistic unbuttonedness, groping for words for what are themselves mere gropings for ideas, he does neither philosophy nor education any good. But that is not philosophy as practiced by those who have known their craft -- by McTaggart and Moore, by Broad and Price and Lovejoy. Surely no one who has understood these philosophers could regard as anything but important what they were trying to do. Well, what have they been trying to do?

They have tried to supplement the work of science in at least two respects. In both of these respects science has to be extended if our thirst for understanding is to be satisfied, but in neither of them do scientists take much interest. The fact is that, logically speaking, philosophy begins before science does, and goes on after science has completed its work. In the broad spectrum of knowledge, science occupies the central band. But we know that there is more to the spectrum than this conspicuous part. On one side, beyond the red end of the spectrum, there is a broad band of infrared rays; and on the other side, beyond the violet end, are the ultraviolet rays. Philosophy deals with the infrareds and the ultra-violets of science, continuous with the central band but more delicate and difficult of discernment.

Take the red end first. Consider the sense in which philosophy comes before science. Many of the concepts the scientist uses and many of his working assumptions he prefers to take for granted. He can examine them if he wishes, and some scientists do. Most do not, because if they waited till they were clear on these difficult basic ideas, they might never get to what most interests them at all. But it would be absurd to leave these basic ideas unexamined altogether. This somewhat thankless preliminary work is the task of the philosopher.

We referred to these unexamined ideas as concepts and assumptions. Let us illustrate the concepts first.

Common sense and science are constantly using certain little words of one syllable that seem too familiar and perhaps unimportant to call for definition. We say, "What time is it?" "There is less space in a compact car," "There was no cause for his taking offense," "He must be out of his mind," "I think these strikes are unjust to the public." Consider the words we have used: 'time', 'space', 'cause', 'good', 'truth', 'mind', just', 'I'. If someone said to us, "What do you mean, I?" or, when we asked what time it was, "What do you mean by 'time'?" we should probably say, "Oh, don't be an idiot," or perhaps with St. Augustine, "I know perfectly well what time means until you ask me, and then I don't know." I suspect this last is the sound answer regarding all these words. We know what they mean well enough for everyday purposes, but to think about them is to reveal depth after depth of unsuspected meaning. This fact suggests both the strength and the weakness of present-day linguistic philosophy. It is surely true, as this school contends, that a main business of philosophy is to define words. The first great outburst of philosophy in the talk of Socrates was largely an attempt at defining certain key words of the practical life -- 'justice', 'piety', 'temperance', 'courage'. But their meanings proved bafflingly elusive; he chased the ghost of justice through ten books of the Republic and barely got his hands on it in the end. Socrates saw that to grasp the meaning even of these simple and common terms would solve many of the deepest problems in ethics and metaphysics. But we must add that Socrates was no ordinary language philosopher. He was not an Athenian Noah Webster, collecting the shopworn coins that were current in the marketplace; on the contrary, he took special pleasure in showing that at the level of ordinary usage our meanings were muddled and incoherent. Only by refining and revising them could we arrive at meanings that would stand.

Now the scientist who is trying to find the truth about the cause of flu cannot discontinue his experiments till he has reached clearness on the nature of truth or the concept of causality. The political scientist who holds that democracy is in certain respects better than communism cannot remain dumb till all his colleagues have agreed as to the definition of 'good'. These people must get on with their work, and they are right not to stop and moon about ultimates. But these ideas are ultimates after all; we must use them hourly in our thinking; and it would be absurd if, while researchers were trying to be clear about relatively unimportant matters, no one tried to get clear about the most important things of all. And the right persons to make that effort are surely the philosophers. A philosopher friend of mine sat down in a railway car beside a salesman who, recognizing a kindred spirit, poured out a stream of talk about his line. "And what's your line?" he concluded. "Notions." replied the philosopher. That seemed all right to the salesman, and it should be so to us. Notions are the line of the philosopher, such key notions as truth, validity, value, knowledge, without which scientific thought could not get under way, but which the scientist himself has neither the time nor the inclination to examine.

We suggested that it is not only his ultimate concepts but also his ultimate assumptions that the scientist prefers to turn over to others for inspection. Let me list a few and ask whether there is any natural scientist who does not take them for granted. That we can learn the facts of the physical order through perception. That the laws of our logic are valid of this physical order. That there is a public space and a public time in which things happen and to which we all have access. That every event has a cause. That under like conditions the same sort of thing has always happened, and always will. That we ought to adjust the degree of our assent to any proposition to the strength of the evidence for it. These are all propositions of vast importance, which the scientist makes use of every day of his life. If any one of them were false, his entire program would be jeopardized. But they are not scientific propositions. They are assumed by all sciences equally; they are continuous with the thought of all; yet they are the property of none. It would be absurd to leave these unexamined, for some or all of them may be untrue. But the scientist would be aghast if, before he used a microscope or a telescope, he had to settle the question whether knowledge was possible through perception, or whether there could be a logic without ontology. Scientists have at times discussed these matters, and their views are always welcome, but they generally and sensibly prefer to turn them over to specialists. And the specialists in these problems are philosophers.

I have now, I hope, made clear what was meant by saying that philosophy comes before science. It comes before it in the sense of taking for examination the main concepts and assumptions with which scientists begin their work. Science is logically dependent on philosophy. If philosophy succeeded in showing, as Hume and Carnap thought it had, that any reference to a nonsensible existent was meaningless, the physics that talks of electrons and photons would either have to go out of business or revise its meanings radically. If philosophy succeeded, as James, Schiller, and Freud thought it had, in showing that our thinking is inescapably chained to our impulses and emotions, then the scientific enterprise, as an attempt at impartial and objective truth, would be defeated before it started. Philosophy does not merely put a bit of filigree on the mansion of science; it provides its foundation stones.


If philosophy begins before science does, it also continues after the scientist has finished his work. Each science may be conceived as a prolonged effort to answer one large question. Physics asks, "What are the laws of matter in motion?" Biology asks, "What kinds of structure and behavior are exhibited by living things?" Each science takes a field of nature for its own and tries to keep within its own fences. But nature has no fences; the movement of electrons is somehow continuous with the writing of Hamlet and the rise of Lenin. Who is to study this continuity? Who is to reflect on whether the physicist, burrowing industriously in his hole, can break a tunnel through to the theologian, mining anxiously in his? Surely here again is a task that only the philosopher can perform. One way of performing it, which I do not say is the right way, is suggested by the definition of philosophy as the search by a blind man in a dark room for a black hat that isn't there, with the addendum that if he finds it, that is theology. It may be thought that since no two true propositions can contradict each other, the results of independent scientific search could not conflict, and that there is no problem in harmonizing them. On the contrary, when we examine even the most general results of the several sciences, we see that they clash scandalously and that the task of harmonizing them is gigantic. Indeed the most acute and fascinating of metaphysical problems arise in the attempt to reconcile the results of major disciplines with each other.

How are you to reconcile physics with psychology, for example? The physicist holds that every physical event has a physical cause, which seems innocent enough. To say that a material thing could start moving, or, once started, could have its motion accelerated or changed in direction without any physical cause, would seem absurd. If you say that a motion occurs with no cause at all, that is to the physicist irresponsible; if you say that it represents interference from outside the spatial order, it is superstitious. Now is not the psychologist committed to saying that this interference in fact occurs daily? If my lips and vocal cords now move as they do, it is because I am thinking certain thoughts and want to communicate them to you. And the only way in which a thought or desire can produce such results is through affecting the physical motions of waves or particles in my head. It will not do to say that only the nervous correlates of my thought are involved in producing these results, for those physical changes are not my thoughts, and if my thoughts themselves can make no difference to what I do, then rational living becomes a mummery. My action is never in fact guided by conscious choice, nor anything I say determined by what I think or feel. Common sense would not accept that, nor can a sane psychology afford to; the evidence against it is too massive. And what this evidence shows is that conscious choice, which is not a physical event at all, does make a difference to the behavior of tongue and lips, of arms and legs. Behavior may be consciously guided. But how are you to put that together with the physicist's conviction that all such behavior is caused physically? That is the lively philosophical problem of body and mind.

Conflicts of this kind may occur not only between natural sciences but between a natural and a normative science. Take physics and ethics. For the physicist all events -- at least all macroscopic events -- are caused; that is, they follow in accordance with some law from events immediately preceding them. This too seems innocent enough. But now apply the principle in ethics. A choice of yours is an event, even if not a physical event, and thus falls under the rule that all events are caused. That means that every choice you make follows in accordance with law from some event or events just preceding it. But if so, given the events that just preceded any of my choices, I had to do what I did do; I could not have done otherwise. But if that is true, does it not make nonsense to say in any case that I ought to have done otherwise, since I did the only thing that I could have done? But then what becomes of ethics as ordinarily conceived? If the scientific principle is true, one will have to rethink the ethical ground for remorse and reward and punishment and praise and blame. This is the ancient problem of free will, which was discussed with fascination by Milton's angels while off duty from their trumpets, and is discussed with equal fascination by undergraduates today.

To be sure, there are people nowadays who say that these old metaphysical issues are really only linguistic and disappear with a due regard to common usage. Thus when we see a man making something happen and know that he is not acting under coercion or some special inducement, we say he is acting freely; that is standard usage and hence correct usage; hence when we say that the man is acting freely, we are speaking correctly; hence we are acting freely; and hence there is no problem. I am not convinced. No doubt the man is acting freely in the sense chosen. Unfortunately this sense is irrelevant to the metaphysical issue. For what the determinist is saying is that even when we are not under any sort of coercion in the ordinary sense, our choices still follow from causes; and whether that is true is not to be settled by studying the plain man's language, for the chances are that he has never thought about it; nor would he necessarily be right if he had.

There are many other conflicts like the two we have mentioned. They fall in no one of the disciplines, but between them, and they must be arbitrated by an agency committed to nonpartisanshjp. The only plausible nominee for this post is philosophy. Philosophy is the interdepartmental conciliation agency, the National Labor Relations Board, or if you prefer, the World Court, of the intellectual community. Like these other agencies, it has no means of enforcing its verdicts. Its reliance is on the reasonableness of its decisions.

We are now in a position to see the place of philosophy in the intellectual enterprise as a whole. Intelligence has shown from the beginning a drive to understand. To understand anything means to grasp it in the light of other things or events that make it intelligible. The first great breakthrough of this drive was the system of common sense, which was molded into form by millennia of trial and error. This system is being superseded by science, whose network of explanation is far more precise and comprehensive. Philosophy is the continuation of this enterprise into regions that science leaves unexplored. It is an attempt to carry understanding to its furthest possible limits. It brings into the picture the foundations on which science builds and the arches and vaultings that hold its structures together. Philosophy is at once the criticism and the completion of science. That, as I understand it, is what all the great philosophers have been engaged upon, from Plato to Whitehead.

They may never wholly succeed. It is quite possible that men will use such understanding as they have achieved to blow themselves and their enterprise off the planet. But while they do allow themselves further life, the enterprise is bound to go on. For the effort to understand is not a passing whim or foible; it is no game for a leisure hour or "lyric cry in the midst of business." It is central to the very nature and existence of man; it is what has carried him from somewhere in the slime to the lofty but precarious perch where he now rests. The drive of his intelligence has constructed his world for him and slowly modified it into conformity with the mysterious world without. To anyone who sees this, philosophy needs no defense. It may help in practical ways, and of course it does. But that is not the prime reason why men philosophize. They philosophize because they cannot help it, because the enterprise of understanding, ancient as man himself, has made him what he is, and alone can make him what he might be.