Movements of Thought in the Nineteenth Century
Chapter 15 Science Raises Problems for Philosophy -- Realism and Pragmatism
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WE TURN now from the Bergsonian philosophy to the realistic movement and its reaction on modern science. This realistic movement is, in a sense, a continuation of the rationalism of the eighteenth century, that which went back to the logical structure of the object of knowledge. Over against this rationalism was the empirical doctrine represented by the English school-Locke, Berkeley, and Hume. The empirical doctrine dealt with the structure of the object as it appears in our qualitative experiences. It was interested in the content of the object rather than in its form. And this school attempted to get the structure, the form of the object, out of the relation of the different elements as they appeared in sensation, in impression, in experience. The rationalistic doctrine started with a certain structure which belongs to the object itself; and, of course, the mind was supposed to have immediate knowledge. The empirical school started with the experiences that came through the senses, and tried to find in the association ofsuch experiences the details of the structure of objects.
That structure was largely expressed in two conceptions: one of cause and effect, and the other of substance and attribute. The critical doctrine of Kant, you remember, recognized both elements. And still, Kant's leanings were more toward rationalisni than toward the empirical side. He assumed that the mind must give the form to the object, but this structure was one which was simply a form of the mind and not a form of things-in-themselves. The mind had the forms of the categories, twelve in number, of which the important ones were substance and attribute, and cause and effect. The empirical school had
(327) attempted to show how mere association of the different experiences with each other would lead to the appearance of such conceptions as that of cause and effect and of substance and attribute. Kant recognized that these must be logically antecedent to the object. There could be no object except in terms of substance and of cause.
The recognition that these forms came from the mind led to the idealistic school that undertook to regard the whole of the world as a structure of the mind, applying not simply to categories already fixed in the mind but to the very evolution of the categories themselves. The evolution in this case was that of a self that thought the universe.
When we come to the situation after this Romantic idealistic school, we find that people had abandoned this conception of the self that thinks of the world, but that they retained these two phases of experience, the form and the content. The realistic school undertakes to come back to the formal side of the object, only it approaches it from the standpoint of a new conception, that of the more modern mathematics and logic. These conceptions are of the relations which lie between the ultimate elements of things. They were conceived of not as forms of the mind but as relations that exist in the world. Neither are they regarded as the association of states of consciousness with each other, as the empiricists conceived of them. Until we get to the skeptical statement of Berkeley and Hume, the empiricists assumed that there were relations which answered to the relations which arose in the mind, that is, relations in the world, such as cause and effect, that answered to the association of one experience with another. Of course, they could not prove any such connection, and Kant's critical philosophy came in to present another point of view.
The realists, on the other hand, as distinct from the proponents of these two positions, believe that the relations of elements with each other are directly cognized, directly perceived. They are there. And the relations form some of the elements which are discovered in analysis. If you take an object of knowl-
(328) -edge and analyze it, break it up into its content, you will find not only the substantive content, the impression in experience, but also definite relations. And what the realist does is to attempt to present both of these contents, those which appear in sensuous experience and those which we think, as relations given in the world. The assumption is that we have direct knowledge of these elements and of their relations in the world itself. The relations are no longer dealt with as acts of thought. In the idealistic school the relations were always the impressions of the realizing mind, so that relations were taken back to the thought of the self. Our own selves were parts of the Absolute Self. The realist, on the other hand, assumes the relations as simply there. We think them; and if we think them, they must be there, for we must be thinking something. The something we think is Being. Whether it has existence or not depends on whether it is located in our spatial, temporal experience. Existence is the relation with reference to which other relations are found actually in spatial, temporal experience. But we can think relations which are not in these forms. We can think of various relations existing between things but which do not exist. They must have being, otherwise we could not think them. We have, then, direct relationship or cognitive relationship with the objects of experience and their forms.
The interest of the realist has been in this process of analysis, of breaking up the object of knowledge into its various elements, with the isolation of the connection as well as of the things themselves, carrying with this the doctrine of the external character of relations. The relations do not exist inside of that which is realized; they exist between relata, between elements that are connected with each other. Realism is indicated by the term which implies that that with which we have cognitive relations is real. It is not phenomenal. It is just what it appears to be in experience. But, to find out just what it is, we must discover it as it appears in the analytic, rather than in the synthetic, phase of experience. The synthetic phase of experience was dealt with by the empiricists under the head of "associ-
(329) -ation." If experience B follows after experience A, it becomes associated with it, so that in the future when we have experience A, or one similar to it, the other experience, B, which had been associated with it, arises also. It is purely a mental affair, a connection of these various states with each other.
Thus realism gathers about the world-old problem of epistemology. The form which that problem took, you remember, was dictated by the very development of Renaissance science, which, as finally formulated, set up a world of physical particles moving with reference to each other in accordance with fixed laws. The rest of the world had to be put over into consciousness. While there was supposed to be a world of these physical particles moving in accordance with natural law, the question at once arose: How does man get outside of the world of consciousness? How do you know there is anything else but what you have in your own experience? The epistemological problem has been thought out in this way, on this issue.
As I said, the answer of the realist is to give another statemerit of knowledge. Knowledge is finding a relationship between an object that lies in consciousness and an object that lies outside of it. If you say, for example, that the table here is nothing but a congeries of your own perceptions and images, you have a table anyway. That is an object. You know it. What you ask is how you can get from such an object which lies simply in your consciousness over to the group of electrons which constitute, as you say, the reality of that table. And the question is practically unanswerable when stated in this way. There is no way of getting from the inner to the outer. All is inside your experience; all is consciousness. What the realist says is that this is an improper statement of what knowledge mean... Knowledge is not going from an object already in experience over to something that lies outside of experience which by definition you must reach. It is simply the relationship between the mind and that which it senses, that which it perceives. It is thought in a direct relationship, and that is all that You can say about it. It is a fundamental, connotative, relation
(330) which exists between the mind and that which is known. We have no problem of getting from the object which is in the mind over to an object which lies outside of the mind. What knowledge consists in is this relation between the mind and its object. It is that shift in the conception of knowledge itself which is characteristic of the realistic doctrine. You see this is not the particular form of the question which I have said was practically unanswerable, namely, "How can one get from consciousness over into something that is not consciousness ?" That form of the question arises out of Renaissance science. The realist said the relationships between the mind and the object is an immediate, given relationship.
This was anticipated by the so-called Scottish school, who said knowledge is immediate intuition. But their statement was bound up more or less with the earlier form of the cognitive doctrine. They still kept the object in consciousness as the immediate object of knowledge, and they still set off reality beyond it. The realists said the object is simply the relationship between the mind and the object, a direct cognitive relationship. That relationship in a certain sense guarantees the object, and one of the great problems of the realistic philosophers is, therefore, the problem of error. If knowledge is given in the relationship of the mind and its object, how can there be error? And, of course, there are errors.
What has been of still more importance, perhaps, from the standpoint of the realistic doctrine has been its recognition of the objects of thought as they appear in the process of analysis. The realistic philosophy is one whose method has been analytic. It has sprung from mathematics-mathematics used, however, in the large sense of that term, the sense in which logic and mathematics come together. The earliest of the group, as you might call Leibnitz, goes way back to the Renaissance period. He at least sketched out the implications of the realistic doctrine. He was one of the great mathematicians of the world, one who had an implicit faith in the possibilities of analysis. If, he said, you could take objects of knowledge and analyze them
(331) so that you get back to the ultimate elements, as, for example, in mathematical problems, those immediately given to you, those which in one sense cannot be defined, which can be set up as indefinable but which can be specified in the sense of having their outlines given so that you can combine them with each other, you would be able to build up all possible combinations. You could have charge of the ultimate elements, and all the relationships that lie between, if you just pushed your process of analysis to the limit and got these elements spread out before you, as a watchmaker spreads out the parts of his watches. Then you could get all possible combinations of things.
It is this method with which the realist operates. He wants to get back to those ultimate elements which are just there, given in immediate cognitive relation, and of which there is no question. If you could get back to those ultimate elements, and particularly to the relationships that lie between them, they would be the basis in terms of which you could make all possible combinations. If you can discover those which are not contradictory, those which are tenable, you have the same assurance of your results as in the immediate experience of the ultimate elements themselves. The realists came back, for example, to final definitions of ultimate elements in the world-elements which we make use of in thought itself, the so-called "logical constants." They came back to these ultimate elements and then defined the relationships which could exist between them, and in this way they could build up logical structures which could not be questioned. They found out what the possible relationships could be between all these different elements. This has a very abstract sound, and the achievements of these Mathematicians and logicians are abstract in the highest degree, but they are very penetrating; and they did, as I said, bring together the fields of mathematics and logic.
They carried with them a doctrine which for a while belonged to the realistic field but which is not so certain now. This is the doctrine of the so-called "externality of relations." I have said
(332) the realist analyzes, takes his object to pieces, comes back to ultimate elements and the relationships which exist between them. He isolates the relations from the elements themselves. In this activity the relation is something that we will say is like a wire that connects two different objects together. You can put up a wire and set up different relations between objects strung on it. The relations as such do not affect the object. The relata are connected by means of the relations, but the relations do not exist by themselves. This emphasis upon the externality of relations was brought out in contests between the realists and the idealists, especially the neo-Hegelians of the latter group.
From the standpoint of that latter group, the relation was an internal, not an external, affair. It was not simply a connection set up between different objects, separate relata, but something which affected the very thing related. These relations grew inside of things rather than being connections between independent elements. Take, as an illustration, the Hegelian doctrine of the social individual. We speak of him as having certain relations. He stands in his social group as a citizen, as a member of a family, of this and that group; and all these groups represent various social relations. We might speak of him as a point through which any number of social relations pass. Now, these relations of the man to the people about him are just what constitutes the man. His relations to the members of his family make him what he is. We cannot say that the relationship of father to son is one that lies outside of the character of father and son. We cannot say that here are two different objects connected by means of paternal and filial relations. We cannot substitute something else for this. It lies within the individual, makes him what he is. It is an internal relation so far as the object is concerned. And, not only is it internal, but it makes every individual entering into the relationship different from what he was before that relationship was entered into. You form an acquaintance with someone; it, becomes a friendship. That relationship changes both of you. You are different beings from what you were before. Now the
(333) Hegelian took this situation over into the whole of social and spiritual reality. For him relations are internal, they are thought of as being the very nature of the Absolute Self. The relation is a process of relating. Relating is a process of thinking in the Absolute Self in which our minds are simply finite aspects. Thus relations lie in the very nature of things themselves.
Over against this doctrine, the realists set up one in which relations are external. The process of analysis takes things apart, sets up ultimate relata; and the connections between them, the relations as such, never change the character of the thing related. You can say that new characters arise, but they are simply the expression of the relations existing between the separate elements. The separate elements themselves can never be changed. Connect one number with another number, and perhaps the result gives you a larger bank account, or it may indicate that you have overdrawn your account. Those are very important facts. But they do not change the character of the numbers that are connected with each other by addition and subtraction. These are ultimate elements which remain always what they are. And the relations that exist are what they are. You do not change the relata by their being related.
Thus the realists accept cognition as a simple relationship between the mind and its object. Nothing can be said about it except that it is an immediate relationship between these two. Therefore, in so far as it exists, it presumably carries with it the import of cognition, that is, it carries knowledge, and so the truth of the experience.
But this knowledge has as its fundamental principle that of analysis, a principle which, as I have said, it had taken from mathematics. It is a process which leads to the breaking-up of the object of knowledge into its ultimate elements. The difficulty which the realist got into on this basis was to account, not for knowledge, but for error. In the older theory the object was given in consciousness as the immediate object of knowledge. That is, the organization of one's percepts, ideas, images, mean-
(334) -ings, as they lay in consciousness, into the immediate object of logical problem was found in knowledge is where the epistemological setting up some sort of a relationship between this immediate object of knowledge and the supposed real object outside. That is what we would consider as answering to our perception of a table, for example. If we state the table in terms of our ideas, or our perceptions, we can say that it constitutes an object of knowledge, but that it is not the real object. The real object is a congeries of physical particles that do not get into experience at all. From the point of view of the realistic philosophy, with its analysis, knowledge is of the ultimate elements in the experience itself. And thus the problem becomes one of accounting for error, for mistakes. The experience of the ultimate elements themselves is evidence of the object's being there; otherwise it could not be experienced. Knowledge is the relationship between mind and these ultimate elements. Given this relationship, both mind and the ultimate elements are there. Meaning and cognitive value, as well as other values, are also objects of knowledge. And they, too, have to be related and organized.
Remember, the external character of relations is a fundamental point in the position of the realist. The relation does not lie inside of the object. It is simply the connection between the ultimate elements. The so-called "meaning" of the object is nothing but an organization of the relations that lie between these different elements. For example, we have the relationship of distance which exists between different objects and our conduct in experience. The groups of distance relations which we find in experience give us the surface of this table, for example. The groups which represent the relation of the individual to each corner, to the different lines, the different spots of color on the surface, taken together, give us our general sense of the distance of the object, as an object, from the organism. It is an organization of the relations which, together, go to make it up. If we want to deal with the meaning of the object, we come back to the various relations which compose it, and get them in their perspective. We may make mistakes in the organization
(335) of these relations, in the meaning they have. We see an eagle soaring over our heads as we lie in the grass, and after a while ,we become aware of the fact that it is nothing but a gnat a few inches away. There are mistakes also so far as the immediate experience goes, that is true enough. But we may also make mistakes when we organize them into ultimate relationships.
But this leaves yet another group of elements in that experience The eagle to which I referred is, after all, something more than a set of separate experiences. It is not only something more than that; it is something universal. It is something that is recognized in any eagle that we see. It is the same, the concept of the eagle, the universal eagle; and it is not only a universal, but it is a unity. We may break the unity up into separate parts, but it is something that belongs to the concept of the eagle. These ultimate universals have to be recognized in their relationship to mind, especially the fundamental universals that appear as logical constants. Not only concepts of this character, but also those of our sensuous experiencesthe reds, the blues, the high and low sounds - are all universals; and we have to deal with them as such. They have to be recognized from a realistic standpoint as something that is there because we think about them. If we think about them, there must be something there to think about.
In the earlier statement which was given, the concept was dealt with as a mental structure of some sort; it was thought of as something in the mind itself. We assume that that which lies in the mind answers to something outside. The realist assumes that our knowledge of the universals is, so to speak, the contact between the universals and the mind; we must put them in the mind but they must also have their existence outside. And yet, many of these universals do not have an existence, in our ordinary use of that term. We imply that a thing is at some point and at some definite time when we say that it exists. If we say a man exists, we locate and date him. If he exists, he does so somewhere and somewhen. But the idea of a
(336) chimera, for example, does not exist anywhere or anywhen. It does not exist. That is very characteristic, of course, of the chimera as such or of any other mythical animals, dragons, and what not, that have played such large roles in mythology and in the imaginations of men. They do not exist, and yet we think about them. If we could regard them as just constructs of the imagination and locate them in people's minds, we could account for their being mere mythical objects. You say there are not any such animals; they do not exist; they are just mental pictures which people have had of possible animals which proved to be impossible animals. But if you take the realistic viewpoint, there must be something to think about-some universal, at least-to which our mind turns and about which we are thinking. There are a good many other things we think about which do not exist. We puzzle our heads over them for a' long time, over perceptions which prove to have contradictions in them. And yet we have been thinking about them. After all, there must have been something. We talk about such things as "round squares." They could not exist-they are contradictions in terms-and yet we can discuss them. As long as we can think about anything, there must be something that answers to the process of thought, and yet many of these things cannot be put into existence.
What this led to on the part of this realistic approach was the recognition of a real being which generally goes under the name of "subsistence" rather than of "existence." There is a world which subsists, but does not necessarily exist. You can have thought occupied in the recognition of the response to all the elements in experience, and not only to these but to everything we call "Idea," that is, any universal. These subsist; some of them exist. Thus, some of them do appear. To apply one of the terms that is used, they have "ingression" into events. This is Whitehead's term for the process. These eternal objects, in the sense that they are outside of time, have ingression into certain events in so far as they constitute things. What you see taking place is the emptying-out of the whole content of the
(337) mind, as the Renaissance philosophers dealt with it, into the world. It is a setting-up of mind as that which has cognitive relationships with all these different elements, allowing the construction to take place through the action of the mind.
But the realist has not been very strong on the constructive or synthetic side. His interest has been in analysis. To understand this interest we have to go back, as I have already indicated, to a mathematical background. One of the greatest of the realists is Bertrand Russell; another is Alfred Whitehead. What they were interested in at first was the perfection of mathematical theory. They were interested in carrying back the mathematical process behind the immediate objects of the physical world that we follow through their various changes. Back of this lay the development of our modern mathematics. Mathematics, for Kant, stood on a basis of Euclidean geometry on one side and of the traditional arithmetic on the other. Kant, you remember, believed that the forms of mathematics were the forms of the mind. Well, not long after the time of Kant two mathematicians undertook to work out geometries which contravened the Euclidean axiom in regard to parallels. It was a question of whether more than one line could be drawn parallel to another line through a point outside that line. They took different points of view, such as that there could be no such line drawn or that there could be a number of them so drawn. The interesting thing was that, starting off with such an axiom, that no lines could be drawn parallel or that there could be an indefinite number of them so drawn, they could build up perfectly consistent systems of geometry. This was not, of course, going back to experience to find a world in which they were true. Neither of these propositions, if true, conforms to the Euclidean axiom, Nor does actual physical experience conform as far as that goes. Of course, this does not go very far. You cannot actually measure the distance between lines so constructed. One mathematician actually undertook to see whether the experiment of setting up triangles or parallels which could be measured on the surface of the earth would hold, but he did
(338) not measure with sufficient accuracy to get any absolute conclusions. What these people wanted to do was not to find parallel lines which act like rails as you look at them. It was a question of seeing whether you could assume that there could be an indefinite number of parallel lines drawn to any line from points outside that line, or if you could assume that there could be no parallel lines. Whichever side you took, you had the basis for a possible geometry. Whichever geometry is right in the sense of describing physical nature, you can prove all the propositions in one or the other. If you come back to experience, so-called, it is, after all, that of one geometry only. Why cannot there be others?
And then, of course, there is always the question as to whether space is curved. We cannot actually follow lines any great length or distance. Do they actually tend to meet? We could never tell if they did. We have another interesting speculation about people who live in a two-dimensional space. Supposing a person were of no thickness at all and lived on the surface of a sphere. Then, if one started to throw something forward in a straight line with sufficient force, it would hit him in the back of the head. How can we tell whether the space in which we live is of one sort or another? Supposing, for example, to give another illustration, we say space is of indefinite extent. What we mean is that, given (or setting up) any limit in space, we imply something beyond it. It is indefinite. Or, supposing we lived in a world which got cooler as we went away from its center, and that in accordance with these conditions the dimensions of things changed, so that the diameters would shrink as they got farther away from the warm center. And assume that the diameters of all objects shrank proportionally. Then as we walked away toward the periphery of the world, we would get gradually smaller and smaller as we got cooler and cooler, and our steps would get shorter and shorter. In such a system we could never reach the limit of the world. We could have an indefinite world inside of a definite one; we would never arrive at the limit; and yet we would never stop. Everything
(339) would become proportionately smaller as we went away from that center.
The value of such an illustration, which is given by Poincaré in his Science and Hypothesis, is simply to show us that our spatial world, which has a right and left, an up and down, is something that is entirely dependent upon our experience. And we have no way of telling whether the world of our spatial experience corresponds to one geometry or another, whether the world is actually Euclidean or non-Euclidean. It is something that is not open to any proof, because our experience will always lie inside our own world. What are these irrefragable difficulties, then? They are proofs for a geometry, provided that the axioms of that geometry are true. We can never tell whether they are true or not. We say a straight line is the shortest distance between two points. We have some difficulty in defining a straight line, but we cannot set it up as indefinable, and it comes back to the statement that it is nothing but the shortest distance between two points. You have to assume it to define it. You come back to certain postulates you set up. On one basis you will set up a Euclidean world; and you can prove certain conclusions in that world, prove that there is such a world. All judgments are necessarily hypothetical judgments. Whether or not there is a Euclidean world we cannot tell. We cannot tell whether the world actually has the dimensions that we think it has or the dimensions of a billiard ball. You could just as well set up all the relationships which you have in the world in one the size of a billiard ball, provided you reduce your units. Why not? Your proofs are dependent upon certain given postulates. It is much easier to prove the Pythagorean proposition if you actually have lines drawn in a Euclidean fashion, a number of them, and work them out. But you are not sure that there is such a Euclidean world. Well, now, is there anything in that Pythagorean proposition which would be true if there were no such Euclidean world? Would it be possible to prove propositions of geometry, and of all mathe-
(340)-matics, without actually accepting the postulates of our empirical world about us?
That is the problem the mathematicians were working on, and what they did was to set up symbols which would be most general and universal and just as few in number as possible. And by means of these and by using the simplest processes of logic, it was possible to prove a whole mathematical science without introducing the postulates of our empirical experience. You can find this done in the Principia mathematica of Russell and Whitehead. In it mathematics is presented in propositions worked out in so-called "symbolic logic"; and the propositions there are propositions which, if translated into Euclidean geometry, would give all the propositions of that geometry, but give them in such a form that they are free from the fixed postulates of our sensuous experience. We free ourselves from all that to a certain degree. We say that the world which seems to have up and down, right and left, really does not have these characters. What we mean by "up and down" is the relationship between the object on the surface and the center of the earth. In this symbolism you come back to a larger, more effective analysis than that worked out in the past, in which you have symbols that refer to universals and the smallest possible number of indefinables. With these you work out propositions that would be true in any world. You do not know, for example, if they are true in the sense that they actually exist. That is the interesting thing, says Russell, about mathematics. You do not know whether what you are presenting is true, and you do not know what you are talking about. You abstract from the content of your postulates. You set up certain indefinable elements and put relationships between them; and then you say that, if such and such a thing exists, a certain result must follow. It was this most generalized form of mathematics which was worked out by these mathematicians; and in accomplishing it, they went beyond the logic of Aristotle, for example, in introducing the so-called "logic of relations." They produced a symbolic logic which was a more
(341) powerful instrument than the Aristotelian syllogism is. And they reduced the content of our exact scientific knowledge to the simplest form in which it could be expressed and to a form which is valid in any sort of world to which you may wish to refer.
They were somewhat excited about their success.This was natural enough. If you can take the whole of the object of mathematical science and trace it to a set of formulas which look very much like the marks of which a stenographer makes use, condense the whole of that to a relatively small number of pages, and have all the content there, you are justified in getting excited. You get a symbolic logic which is very much more effective than the older logic. If you invited twenty people to dinner and some belonged to one religion and some to another, some to one political faith and some to another, and some of them disliked others, and yet you had to seat them about the table so as to have everyone at peace with his immediate neighbors, you would have quite a job on your hands. If you ever have such a job, I advise you to familiarize yourselves with symbolic logic, for that will enable you to state just what the possible combinations are that you can make. It will enable you to arrange your guests in such a way that there will not be any unpleasant experience at the dinner. There are certain situations of that sort which make us aware of the practical value in the use of symbolic mathematics. But I must confess that beyond that, so far as practical things are concerned, its use has been very slight. The achievements which symbolic logic makes in the realm of thought are very impressive, indeed. But we still go on thinking in terms of what has been called the "logic of things," the logic of inference, that is, the logic of Socrates and immortality: all men are mortal; Socrates was a man; therefore Socrates was mortal. That is logic built up on the inherence of certain qualities in certain substances. Well, now, the world we live in is a world of things, and the logic we will continue to utilize will be a logic of things. Symbolic logic gives a powerful discipline, an apparatus which enables us to deal
(342) with relations. But if you continue to work in a world of things, I do not think that symbolic logic will be of any particular value except in such problems as I suggested above.
What I have been trying to bring out was the background of these realistic philosophers. They try to get rid of the epistemological problem by simply recognizing that knowledge is a cognitive relation between mind and the elements. And then they try to state the so-called "objects of knowledge" in terms of their ultimate elements and the relationships between them. And in order to do that, they have to assume the externality of relations, that is, that there is a set of ultimate elements which are related to one another as if by wires or strings. If you want to handle such a number of ultimate elements and their relations, you have to have a very powerful sort of technique, such as that which the symbolic logic gives you. So all these go along together. The realists assume that knowledge is just a relationship between the object and the mind. Then by analysis they break up the object into all its elements, set up cognitive relations between mind and these elements and their relations, and then connect them all together. They give you a technique which enables you to handle these factors.
It is in this field that the realist is occupied. Things are, or at least they have being. Elements, anything we think about, have being; and our problem is, not to determine whether some things have being and others not, but to determine the relationships between these elements of being. And the relationships between these elements also are actually given. They are realized. Things are real. There are different sorts of reality. That of existence, for example, of something located at a certain point at a certain time. But things which do not exist have being, that is, they have subsistence; and the problem is to determine what that means. In this philosophy the problem of the universal as out there has to be recognized as present because universals can be thought about. The problem of the universal, as far as our sensuous experience is concerned, presents some difficulties. The forms in which these universals appear
(343) among different relata are different. For example, Whitehead refers to them as eternal objects. Another group, the so-called "critical realists"- 0Santayana, Lovejoy, and others - refer to them as "essences." And the question of the appearances of these essences, these universals, in the object and the presence of them in the mind becomes a somewhat difficult question. We say, for example, that there is something which constitutes a table. I know what you mean by this term, otherwise we could not talk about the object in question. We attach a particular word to it. We may call it by any word. But there is something we think about, and it is universal. We also assume that it is in this thing. What evidence have we of this? There must be such a thing; otherwise we could not think about it. How do we get it into this relationship? That presents problems which we are not undertaking to follow out, but to criticize this philosophy I want to give you the point of view of a group of influential philosophers whose doctrine belongs to this period. If you want a further account, take Santayana's Skepticism and Animal Faith. These realists had something of the same confidence in the mathematical technique that Kant had in the achievements of Newton.
Philosophy has in this as well as in other centuries occupied itself with the interpretation of what science has accomplished. In modern times science and philosophy are separated from each other. Science reaches certain results. It tests them. We can act upon them. Philosophy has been occupied with the question of meanings. Some philosophers feel that philosophy goes further and can criticize the propositions, the presuppositions of science. But as a general rule it can be said that what philosophy has been doing, especially since the time of the Renaissance, is to interpret the results of science. Well, now, mathematics has been going ahead at a frightful rate during this last century, and the realists represent an attempt to interpret it from the point of view of its own technique. You get very strange results looking at this development of mathematics from our empirical point of view.
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Alongside of this realistic philosophy we find another -- pragmatism -which has developed out of a different aspect of the scientific movements of the period. This doctrine has two outstanding figures: one of them is William James, the other, John Dewey. There are differences in the formulation of pragmatism on the part of these two men. That of James is to be found in his volume entitled Pragmatism; that of Dewey, in his earlier statements in his Essays in Experimental Logic, and in a more elaborate statement in his more recent book, Experience and Nature. Back of the work of both lies the common assumption of the testing of the truth of an idea, of a hypothesis, by its actual working.
Our problem now is to put this statement in relationship to the doctrines which we discussed earlier. In them the test of truth lies in the coherence, the orderliness of ideas, the way in which ideas fit into a general logical structure as it arises in the mind, a mind which is not only a mind but also a creator of the world, all minds being simply phases of a more general, an Absolute, mind. From this standpoint the world was the result of the thought process of the Absolute. Our thinking is but one of the finite and imperfect elements of this process-imperfect because a mere phase. It would be impossible for us to think of the world in a true fashion because of our finite character. But in proportion as our thinking is coherent, to that degree we can assume that our mind approaches truth.
The point that needs particularly to be recognized in an approach to the pragmatic doctrine is the relationship of thinking to conduct. The undertaking of the Romantic idealists and the rationalists was to present thought as that which discovered the world. It had the distinct business of finding out what the nature of things is. That is, cognition is a process which arose, so to speak, for its own sake. One is curious, one wants to know the world; and knowledge is a simple getting of the nature of the world. Its tests lie, from that standpoint, in the product or in the nature of what is known. This is a copy theory of knowledge; one has in his mind the impression of that which exists
(345) outside; or one may have a coherence theory such as that to which I have referred above, that which fits into a structure which lies outside. The function of knowledge in either case is to give as close a resemblance as possible to something which lies outside the mind.
If we approach the world from the standpoint of the sort of experience with which the psychology we have been presuming deals, we can see that intelligence in its simplest phase, and also in a later phase, really lies inside of a process of conduct. The animal, even the plant, has to seek out what is essential to its life. It has to avoid that which is dangerous for it in its life-process. A plant shows its intelligence by driving down its roots, in its adjustment to the climate. When you get into the animal kingdom, You find much more adjustment and an environment which involves more dangers, in which the getting of food, the avoiding of enemies, the carrying-on of the process of reproduction, take on the form of an adventure. Intelligence consists in the stimulation of those elements which are of importance to the form itself, the selection of both positive and negative elements, getting what is desirable, avoiding what is dangerous. These are the ways in which intelligence shows itself.
For example, the intelligence of the human form is one which has arisen through its ability to analyze this world by discrimination, and, through significant symbols, to indicate to other forms with which it works and to the form itself what the elements are that are of importance to it. It is able to set up such a structure of symbols, images, which stand for the object that it needs. Thinking is an elaborate process of selecting, an elaborate process of presenting the world so that it will be favorable for conduct. Whatever 'is its later function -- it has one of knowledge, which is for its own sake-in its earlier phases we have intelligence, and then thought, as lying inside of conduct. That is, the test of intelligence is found in action. The test of the object is found in conduct itself. What the animal needs is its food, freedom from its enemy. If it responds to the right stimuli,
(346) it reaches that food, that safety. The animal has no other test as to whether it has made such a proper selection except in the result attained. You can test your stimulus only by the result of your conduct which is in answer to it. You see, that takes the research method over into life. The animal, for example, faces a problem. It has to adjust itself to a new situation. The way in which it is going brings danger or offers some unexpected possibility of getting food. It acts upon this and thus gets a new object; and if its response to that object is successful, it may be said to be the true object for that stimulus. It is true in the sense that it brings about a result which the conduct of the animal calls for. If we look upon the conduct of the animal form as a continual meeting and solving of problems, we can find in this intelligence, even in its lowest expression, an instance of what we call "scientific method" when this has been developed into the technique of the most elaborate science. The animal is doing the same thing the scientist is doing. It is facing a problem, selecting some element in the situation which may enable it to carry its act through to completion. There is inhibition there. It tends to go in one direction, then another direction; it tends to seek this thing and avoid that. These different tendencies are in conflict; and until they can be reconstructed, the action cannot go on. The only test the animal can bring to such a reconstruction of its habits is the ongoing of its activity. This is the experimental test; can it continue in action? And that is exactly the situation found also in science.
Take such a problem, for example, as that of the radiation of the sun or of the stars. It is assumed that that radiation is due to the compression which comes with attraction. Then, knowing what the mass of the star is, what the direction of attraction is, and the compression that follows from it , one can figure out how much heat the star can radiate. On that basis it was figured out some forty years ago that the sun has not been in its present condition for a period of more than twenty million years and that it might be perhaps seventeen million years before it became dark and cold, so far as the earth is concerned.
(347) Geologists, on the other hand, were turning back the pages of the history of the earth and working out its history. In this process they got various tests as to what the time periods had been. And all these tests called for far longer periods than the astrophysicist was willing to grant. The former dealt in terms of a hundred million years. In recent research we have discovered a new test which is perhaps the most accurate of all; that is the radiation of radioactive bodies. We know, for example, that bodies of this type are continually breaking down. We can see them doing it. In the dark we can see the sparkling which represents a continual discharge of energy, the breaking-down of higher atomic structures into lower. At first this process seemed to be indefinite; but when it was worked out, it was found that such a process in radium might last for several hundred years. The rate of disintegration could be figured out. We know something about the elements, the parts of the earth, that are radioactive; and in that way we can determine what the rate is at which certain minerals which result from such a disintegration as this could have formed, how long a time would be necessary to build them up. Taking this and all the other tests, the scientists set up their theory of the history of the world-the geologist writing his history on one time schedule, and the physicist writing his on the basis of another. We get a clash here. One calls for a period of several hundred million years; the other denies any period longer than twenty million years. There you get a typical scientific problem.
What I want to point out is that it stops the scientist in his process of reconstructing the past. You are reconstructing it on one doctrine or the other. You cannot use both of them. And yet there are facts which lie behind each of them. What is the source of the energy of the sun? It is not burning up coal. It undoubtedly produces heat by the very compression that follows from attraction. That is the only source of heat which can be found. On that basis the age of the earth is twenty million years. And yet, here we have a history which the geologist and the archeological zoologist and the botanist have been writing
(348) on the basis of other data. And the two stop each other. The process of writing the history of the earth cannot be continued, because the two theories are in conflict with each other. You have these exceptional situations arising over against each other. What is taking place is the recognition that there is another source of energy which has not been attacked, so to speak, in the doctrine of the scientists themselves. This very energy, which is found in the process of radiation which we make use of in our radium watches and clocks, represents a source of energy which the suns may themselves be drawing upon. In its process of radiation, the sun is actually turning out more than four million tons of energy per square yard every few minutes. It is using itself up. Its mass is passing over into the form of radiation. We know that light has weight. Of course, that weight represents just so much mass. Mass must come from the radiation of the sun. The sun is breaking down its own atoms and getting the energy that is in them. We do not know just what the exact process is by which this takes place, whether it is due simply to the immense crushing power of such a great mass as that at the center; but we know that there is much energy in an atom. If you could explode an atom, I think it is said that you could carry the S.S. Leviathan across the ocean on the amount of atomic energy found in a drop of oil-perhaps it is two or three drops if you like, I have forgotten the figures-but there is an enormous amount of energy shut up in the structure of the atoms themselves.
Given such a problem as that, what does the scientist do? He proceeds to start to write his history of the stars as he finds them, the giant and the dwarf stars, the white and blue and red stars, in their different stages of evolution. He starts to write of them on the basis of the hypothesis that these suns have been continually expending the energy involved in their atomic structure in the form of radiation. And that is brought, of course, into its relationship with the geological and biological history of the earth. Could one go on writing the history of the
(349) stars and of the surface of the earth so that they do not come into conflict with each other? It was found that there 1 is plenty of time provided under the now recognized form of expenditure of the energy of the sun -- a hundred million years or so, instead of twenty million years. So the process of interpreting the world, working out the scientific statement by means of the new hypothesis, could be continued.
Now, what constitutes the test of the hypothesis? The test of it is that you can continue the sort of conduct that was going on. It is the same sort of test which the animal finds. If it finds itself in a difficult situation and sees escape, it rushes off in that direction and gets away. That is a fair test, for it, of what we call a hypothesis. It did not present ideas to itself in terms of significant symbols, but it was a good working hypothesis. It could continue its action of living that way, where it could not have continued it otherwise.
Well, in the same fashion, from a logical standpoint, the scientist is engaged in stating the past history of the world, and he comes up against this blank wall of insufficient time. Now, when he collates the history of the surface and the history of the radiation of the sun, he gets a clue -- a hole, so to speak-which will let him escape from that difficulty. That constitutes the test of the truth of his hypothesis. It means that he can continue the process of stating the history of the world within which he is living. And, of course, the process of stating the world, stating our past, is a process of getting control over that world, getting its meaning for future conduct.
That is the importance of the pragmatic doctrine. It finds its test of the so-called "true" in hypotheses and in the working of these hypotheses. And when you ask what is meant by the "working of the hypotheses," we mean that a process which has been inhibited by a problem can, from this standpoint, start working again and going on. just as the animal no longer stands there, dodging this way and that to avoid its enemy, but can shoot away and get out of danger, so the scientist does not simply have to stand before a history which allows him only
(350) twenty million years and a history of two or three hundred million years. He can now continue the process of giving the history of the world, having this conception of the source of energy which had not been recognized before. Putting it into behavioristic terms, what we mean by the test of the truth is the ability to continue a process which had been inhibited.
A certain statement of the pragmatic doctrine implied that a thing was true if it satisfied desire. And the critics of the doctrine thought that this satisfaction meant the pleasure one could get out of it. That is, if a hypothesis was pleasing to an individual, then it was true. What I have just stated is, however, what is implied in this doctrine - that the test of truth lies in the continued working of the very processes that have been checked in the problem. It is a pleasant thing to get going again after we have been caught and shut in. It is a pleasant thing to have a new planet swim into our ken. But it is not pleasure which constitutes the test, but the ability to keep going, to keep on doing things which we have been trying to do but which we had to stop. That is one phase of the pragmatic doctrine-the testing of a hypothesis by its working.
The other phase I have touched on earlier. You see the attitude of which I have been speaking brings the process of knowing inside of conduct. Here, again, you have a relationship between pragmatic doctrine and the behavioristic type of psychology. Knowing is a process of adjustment; it lies within this process. Cognition is simply a development of the selective attitude of an organism toward its environment and the readjustment that follows upon such a selection. This selection we ordinarily connect with what we call "discrimination," the pointing-out of things and the analysis in this pointing. This is a process of labeling the elements so that you can refer to each under its proper tag, whether that tag is a pointing of the finger, a vocal gesture, or a written word. The thinking process is to enable you to reconstruct your environment so that you can act in a different fashion, so that your knowledge lies inside of the process and is not a separate affair. It does
(351) not belong to a world of spirit by itself. Knowledge is power; it is a part of conduct that brings out the other phase that Is connected with pragmatism, especially in Dewey's statement.
This phase is its instrumentalism. What selection, and its development into reflective thought, gives us is the tools we need, the instruments we need to keep Lip our process of living in the largest sense. Knowledge is a process of getting the tools, the instruments. Go back to the illustration I have used above of the atoms as a source of energy. This concept becomes a tool by means of which the length of the life of the stars can be estimated. And when you have that, you can relate it to the age of life on the surface of the earth.
Perhaps the best statement to bring out the importance of this instrumentalism is the term "scientific apparatus." We think of that generally as the actual tools of the scientist; but we know that the term "apparatus" is also used for the ideas, the units, the relations, the equations. When we speak of a scientist's apparatus we are thinking of the very ideas of which he can make use, just as he can use the things which he has in his laboratory. An idea of a certain type, such as that of the energy of an atom, becomes a tool by means of which one is able to construct the picture of a star as a source of energy. There, you see, the object as such is a means which enables one to carry on a process of reconstruction such as is given in scientific doctrine.
Well then, the sources of the pragmatic doctrine are these: one is behavioristic psychology, which enables one to put intelligence in its proper place within the conduct of the form, and to state that intelligence in terms of the activity of the form itself; the other is the research process, the scientific technique, which comes back to the testing of a hypothesis by its working. Now, if we connect these two by recognizing that the testing in its working-out means the setting-free of inhibited acts and processes, we can see that both of them lead up to such a doctrine as the one I have just indicated, and that perhaps the most important phase of it is this: that the process of knowing
(352) lies inside of the process of conduct. For this reason pragmatism has been spoken of as a practical sort of philosophy, a sort of bread-and-butter philosophy. It brings the process of thought, of knowledge, inside of conduct.
Because pragmatism has these two aspects, it will be well to spend a little more time in their consideration. The first phase is that of the motor psychology. We have referred to its development into behaviorism. The other phase of the problem is that of the scientific method. The rationalistic philosophies assumed a certain structure of the object as being given in the nature of the object itself, a certain structure of knowledge which the object has and which also lies in the mind-as some thought an innate idea, others a something which the mind could directly perceive. The psychological approach of the empiricists translated this structure of the object over into the relations of states of consciousness to each other. Substance and attribute, cause and effect, and the other so-called "categories" were stated in terms of the mere association of different states of consciousness with each other. If they happened to be associated in a certain way, certain structures arose; if associated otherwise, other structures would have arisen. But they were not structures directly, not objects as such. They were mental structures, subject to mental laws. It was generally assumed that there were structures of things that answered to these mental structures, that lie behind them, as illustrated in the so-called "causal theory of perception," the theory that our mind is causally affected by things and that these things impress themselves on the mind and that with these impressions come not only the sense qualities but also the relations of these qualitative elements to each other. That is the structure of the object. Both rationalism and empiricism assumed that there are certain structures in the object which the mind gets hold of, and that it is through these structures that one can know the laws of causation, the laws of the relationship of qualities to substances, and so on. Particularly, however, it was in the law of causation that science and philosophy found the reality of
(353) things. What were the uniform successions of events to each other in a causal series? Everything, as far as possible, was carried back to causal laws or uniformities.
The history of science since the Renaissance is really a history of the research process. At first this research was conceived of, and still is largely conceived of, as a simple discovery of something which is out there. Discoveries followed each other closely, so that one statement of the object was rapidly succeeded by another statement. This seemed only natural, because men were finding out more about the world through the scientific method. And this new scientific method carried with it another criterion than that which belonged to the older period, the criterion of experiment, of experimental tests, of experimentation that included observation. Exceptions arose, we have seen, and a problem was formulated, and then a hypothesis for the solution of the problem was presented, and then this solution had to be tested. That is, one had to see whether or not this new hypothesis would work. If it did, then the hypothesis became an accepted theory; if it did not, a new one was substituted for it and subjected to the same test.
This test or experiment-the research method-in some sense took the place of the mathematical method in which one proceeded seemingly by demonstration, by deduction. At least the assumption of the latter was that, if one had all the ultimate elements of things, one could deduce from their mathematical relations what the structure of the world is. This was essentially the position of Descartes. He assumed that he could conceive of the world as made up of ultimate spatial elements which were moving with reference to each other, and, given this motion and the spatial elements, could work out what the structure of things must be. He identified matter with space itself and assumed a great whirl of this, with the consequent movement of all the different particles in relation to each other; and he undertook to show how the world arose out of such simple motions. He undertook to do this by means of the mathematical laws of physics. Leibnitz also assumed that, if one could only
(354) get hold of these ultimate laws, it was conceivable that one could work out the nature of things from them. In fine, the rationalist went on the assumption that there were certain structures of things of which the mind got hold.
The practice of research science, which I have described at some length above, was continually to approach, continually to seek for, new problems, and with these new problems to find new hypotheses. And these new hypotheses brought with them new worlds which took the place of the old worlds. The test of them was one which lay in the experience of man. It was to be found in the actual process of cognition as it lay in experience itself. The test became the ultimate test, and from this standpoint the mathematical theory simply presented an apparatus for working out hypotheses, for determining what the situation must be within which the test could take place. But the assurance in regard to new hypotheses, with their new structure of the world, rested upon the test of experience itself. It is this scientific method, which finds the test of the truth of a hypothesis in its working, that has got its philosophic expression in the pragmatic doctrine.
This doctrine is nothing but an expression of the scientific method, which is an experimental method. It has advanced by the positing of hypotheses. It has advanced from problems toward their solution, and these problems have called for analysis. And in the case of changes that we have been describing, this analysis is of the type mentioned above. But, besides these analyses, it is necessary that the scientist should present some hypothesis as a solution to the problem. The hypothesis is not simply a statement of the ultimate elements and the relations between them. If that were the case, one's thinking would be mere deduction, mere demonstration. Given the elements and their relations, we can see that possible combinations can be made and conclusions deduced. That leads to the curious situation that Poincaré has pointed out, that in mathematical science we seem to advance simply by drawing the necessary conclusions from the premises. In that case there should be nothing
(355) in the conclusion which was not in the premises; and yet these sciences have advanced from one achievement to another, discovering that which is new, reaching results which are foreign to the positions from which thinking started. Mathematical science has not been simply a recording of the necessary results which can be drawn from a set of given premises. It has been an achievement such as that found in the physical sciences. For example, within mathematics itself we have seen the development of so-called "transcendental numbers." How shall we explain this: that we get, by a purely deductive process, results not found in the premises? Actually, the conclusion that we have to reach is that we are not using simply a deductive process. For, after stating our problem by means of the most penetrating analysis, we reach a point at which a reconstruction of thought takes place. The scientist, including the mathematician, presents a hypothesis and then tests it. In mathematics this testing of the hypothesis is generally hidden, covered up. The way in which the mathematician or mathematical scientist justifies himself is by giving a necessary line of reasoning, and one loses the point at which the hypothesis is made.
Put it in this way: If you should take any other view of the world than our own-such as that expressed by the Ptolemaic theory, the geocentric theory of the world-on the basis of that account you could state the positions of all the different planetary bodies; you could tell where they would all be, could predict eclipses, and other relations. Up to some time in the eighteenth century you could have covered the whole field of astronomy by a Ptolemaic account of the world. But, by working out that doctrine with all its implications, you could not have deduced from it the Copernican, the heliocentric, theory. By the most complete set of deductions possible you could not have reached the latter theory as a necessary result of the former. When one has accepted the statement of the Copernican theory that the sun is the center, then you can show why the conclusions that you drew from the Ptolemaic theory were accurate. You can show why it is that, when the sun seems to
(356) revolve about the earth, you can get the same statement of the relative positions of sun and earth and the other planets whether you regard the earth as revolving on its axis or the sun as revolving about the earth. You can take the geocentric theory with the heavens revolving about the earth, or the heliocentric with the earth as revolving about the sun, and show that in either case you get the same relative positions of the different bodies. That is, you can deduce the results of the Ptolemaic theory from the results of the Copernican theory. But you could not move in the opposite direction at the time when the Copernican theory took the place of the Ptolemaic. To put it in a more general form, later hypotheses which you present and accept must be able to take up into themselves all the facts gathered before, all the results which have been attained; and they must be able to show how these results were reached. But you cannot advance by a mere process of deduction from an earlier to a later hypothesis. Of course, if your later hypothesis is merely a correcting of errors, you can. If a statement of your bank account is not right, you can go back and find the mistake. But you cannot deduce later theories from earlier ones. You cannot deduce the theory of electromagnetism from a theory of solid atoms. But, given the theory as it is being worked out, we can state mass in terms of electromagnetism. From the standpoint of mathematical science, we seem always to have only a process of deduction; and the point at which the new hypothesis comes in is one which is very apt to be completely hidden. It is not realized that this has taken place in the mind of the scientist who has a new idea, for, just as soon as he has a new idea, he states the whole in terms of a set of equations where the results follow necessarily from the premises. And in this way he covers up the hypothesis that he has fashioned. Actually, the hypothetical method is essential to development even inside the field of exact mathematics.
Mathematical technique has shown itself peculiarly powerful in dealing with problems which science has approached. It succeeded, for example, in dealing with the problem of change.
(367) That problem was never attacked by the ancient world, that is, the problem of change while it is occurring. The ancient world considered change in terms of qualitative elaboration, in terms of degeneration and decay, but always from the point of view of the result being attained. Motion, in particular, was studied in terms of spaces which were in the past, in times which had elapsed. The ancient thinkers never undertook to deal with each change while it was going on.
Now, that is just the problem that presented itself in dealing with what in modern mathematics are called "acceleration" and "deceleration," that is, increase and decrease in velocity. How can you estimate the change that is uniformly taking place within change itself? You have a body moving toward the earth. You can measure the length of the fall and the time of the fall. But this fall is not one in which velocity has been constant. On the contrary, its velocity has been uniformly increasing. That seemed to mean that the ratio between the distance passed over and the time elapsed is itself continually changing. And yet this ratio always means a certain distance passed over in a certain elapsed time. That is, you have to take a certain distance and a certain time as uniform. We say that a body has fallen so far in a half or in a thousandth of a second, and that its velocity is such and such. That means it has passed over this fixed portion of its path in this fixed time. Then the next portion may represent a ratio which gives a greater time or a greater space. But each portion of it has to be treated as if it were fixed. The problem of the falling body is the problem of a process in which the velocity is uniformly increased. It is that problem that the "infinitesimal calculus," as Leibnitz termed it, or "fluxions," as Newton called it-terms which refer to identical methods, at bottom was invented to solve. These are the methods which mathematics has used for dealing with a seemingly insoluble problem. What Leibnitz and Newton did was to find a way of stating numbers in terms of infinitesimals, of distances that are so slight, times so short, that they can be neglected. A more accurate statement was one in which
(358) these distances were stated in terms of the law of change. A still more satisfactory treatment was a statement in terms of limits. That is, it was found out that as one approached a certain limit a certain law was indicated. And it was assumed, then, that this law must be true of the limit itself. What was true of the different situations as you approached this limit, so to speak, must be true of the limit itself.
There are different ways of stating a mathematical procedure by means of which, as I have said, the scientist was able to deal with the law of change while that change itself was occurring-of getting at the law of the change of a change. It is this that has enabled science to get inside of, and to deal with, a process that is going on. The method is one of analysis which goes farther and farther and discovers laws by means of this continued analysis. It was the effectiveness of this analysis which gave prestige to mathematics. It was no longer simply a static science of Euclidean geometry, no longer a mere statement of equations between static quantities; it was a method by means of which one could get inside the processes which were themselves going on, and get the laws of those changes which were occurring.
As I have said, the realistic philosophy has been a generalization, in some sense, of this mathematical method which has been so remarkable in its achievements. It has enabled the scientist to enter all sorts of fields-those of the changes of air, of fluids of all sorts; those of the changes with which physics and chemistry have to deal; those of the changes of heat, for example. It was a method which, by its analysis, was able to get back to ultimate elements-ultimate at least for the time being -and get relations existing between these elements even when the relations were changing. Knowledge, then, seemed to consist in getting hold of ultimate elements and the relations between them and also the study, as I have said, of the relations of relations, the changes of changes. It seemed to consist in getting hold of the ultimate elements and relata and the relations between them. That has been the goal of realistic thought.
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This movement and the pragmatic are the two which are peculiarly characteristic of the modern period, for both of them grow out of phases of the scientific process: the one arises out of the mathematical technique which has been greatly generalized, so that it goes into the field of pure logic in which mathematics and philosophy are brought together; the other is a development of the technique of experimental science and the recognition that the test of a hypothesis lies in the successful solution of a problem and that human advance consists in the solution of problems, solutions that have to be stated in terms of the processes that have been stopped by the problem. Progress is not toward a known goal. We cannot tell what the goal is toward which we are moving, and we do not test our movements or direct them according to any fixed goal that we can set up. What we do do, in the face of difficulties or problems, is to seek solutions. We seek a hypothesis which will set free the processes that have been stopped in the situation that we call problematic.
There has been a neo-Idealism in our modern philosophic thought too; but it has not played a very important part, and I will not complicate the picture by introducing it.
