Extract From: Burtt, E.A. (1932). "Chapter VIII. Conclusion" (pp. 301-325). In The Metaphysical Foundations of Modern Physical Science (2nd Rev. ed.). London: Routledge & Kegan Paul. [*Page numbers correspond to the 1980 soft-cover Humanities Press edition.]

CHAPTER VIII. CONCLUSION

.... [p. 310]....

It may be worth while to examine at somewhat greater length the third phase of the Newtonian metaphysic; namely its doctrine of mind, for it is at this point that philosophical criticism has already shown itself to best advantage in dealing with the metaphysical problems arising from modern science, and it may well be that its distinctive contribution in the future is along this line also. English idealists and realists from Berkeley down have been largely occupied in pointing out that the popular form of the Cartesian [interactive mind-body] dualism, with its [ontological] conception of mind as substantially different from physical matter and yet to be located in the physical brain is suicidal to science herself -it makes all knowledge of the world of science impossible and inconsistent [(because it springs from an epistemological subject-object dualism in which a barrier of the senses is assumed)]- while the German idealists [(e.g., Kant)] and their followers have largely attempted to show that the very existence of science, as well as of art philosophy and human civilization generally, imply the ascription of a reality and nature to mind widely different from that admitted in the traditional [subject-object] dualism.

Let us critically summarize the situation with reference to each of these points commencing with the former [Cartesian variety]. An appropriate text for this particular question will be found in [p. 311] that highly interesting [epistemological] statement of Descartes [(1644)] which has already been twice quoted: "When any one tells us that he sees colour in a body or feels pain in one of his limbs, this is exactly the same as if he said that he there saw or felt something of the nature of which he was entirely ignorant, or that he did not know what he saw or felt." We have discovered in the course of our historical analysis sufficient reason to believe that in its first inception by Galileo and Descartes this [barrier of the senses] position was buttressed by nothing more than mathematical apriorism, but of course, it has rarely, if ever, been avowedly based thereon. [For example, this mathematical apriorism seems to have had a hand in Newton's own change of mind about the location of color. In his early naturalistic report (1675), color was treated as one of the "original properties" of sunlight, but these initial statements regarding the physical components of sunlight were eventually qualified along more "philosophical" lines by the time of his Opticks (1704) -in which he reasons that since wavelengths are measurable while color is not, color is not in the light but is located in us. Here we see a position very similar to both that proposed by Galileo (1623) regarding sound and to Locke's more recent formal doctrine of "primary and secondary" qualities (1690).] As developments continued in the sciences of physiology and of optics, thinkers who had already taken the [subject-object] dualism over from the giants of science supposed themselves to have gathered sufficient empirical arguments to maintain the position. Professor [T.H.] Huxley in his Helps to the Study of Berkeley, offers a typical recent defence of the situation as accepted by the bulk of modern scientists.

Suppose that I accidentally prick my finger with a pin. I immediately become award of a condition of my consciousness -a feeling which I term pain. I have no doubt whatever that the feeling is in myself alone; and if anyone were to say that the feeling is something which inheres in the needle, as one of the qualities of the substance of the needle, we should all laugh at the absurdity of the phraseology. In fact, it is utterly impossible to conceive pain except as a state of consciousness.

Hence, so far as pain is concerned, it is sufficiently obvious that Berkeley's phraseology is strictly applicable to our power of conceiving its existence -its being is to be perceived or known, and, so long as it is not actually perceived by me, or does not exist in my mind, or that of any other created spirit, it must either have no existence at all, or else subsist in the mind of some eternal spirit.

So much for pain. Now let us consider an ordinary sensation. Let the point of the pin be gently rested upon the skin and I become aware of a feeling, or condition of consciousness, quite different from the former -the sensation [p. 312] of what I call "touch." Nevertheless this touch is plainly just as much in myself as the pain was. I cannot for a moment conceive this something which I call touch as existing apart from myself, or a being capable of the same feelings as myself. And the same reasoning applies to all the other simple sensations. A moment's reflection is sufficient to convince one that the smell, and the taste and the yellowness, of which we become award when an orange is smelt, tasted, and seen, are as completely states of our consciousness as is the pain which arises if the orange happens to be too sour. Nor is it less clear that every sound is a state of the consciousness of him who hears it. If the universe contained only blind and deaf beings, it is impossible for us to imagine but that darkness and silence would reign everywhere.

It is undoubtedly true, then, of all the simple sensations, that as Berkeley says, their "esse" is "percipi" -their being is to be perceived or known. But that which perceives, or knows, is termed mind or spirit; and therefore the knowledge which the senses give is, after all, a knowledge of spiritual phenomena.

All this was explicitly or implicitly admitted, and indeed insisted upon, by Berkeley's contemporaries.... with respect to these secondary qualities [Huxley, T.H., (1896). Helps to the Study of Berkeley. In Hume. New York: D. Appleton and Company, p. 251, ff.].

Huxley proceeds to discuss the idea of primary qualities [-Locke's term (1690)-] as held at Berkeley's time [(1709, 1710, 1713)], and then returns to his experiment of the pin.

It has been seen that when the finger is pricked with a pin, a state of consciousness arises which we call pain; and it is admitted that this pain is not a something which inheres in the pin, but a something which exists only in the mind, and has no similitude elsewhere.

But a little attention will show that this state of consciousness is accompanied by another, which can by no effort be got rid of. I not only have the feeling, but the feeling is localized. I am just as certain that the pain is in my finger, as I am that I have it at all. Nor will any effort of [p. 313] the imagination enable me to believe that the pain is not in my finger.

And yet nothing is more certain than it is not, and cannot be, in the spot in which I feel it, nor within a couple of feet of that spot. For the skin of the finger is connected by a bundle of fine nervous fibres, which run up the whole length of the arm, to the spinal marrow, which sets them in communication with the brain, and we know that the feeling of pain caused by the prick of the pin is dependent on the integrity of those fibres. After they have been cut through close to the spinal cord, no pain will be felt, whatever injury is done to the finger; and if the ends which remain in connexion with the spinal cord be pricked, the pain which arises will appear to have its seat in the finger just as distinctly as before. Nay, if the whole arm be cut off, the pain which arises from pricking the nerve stump will appear to be seated in the fingers, just as if they were still connected with the body.

It is perfectly obvious, therefore, that the localization of the pain at the surface of the body is an act of the mind. It is an extradition of that consciousness, which has its seat in the brain, to a definite point of the body -which takes place without our volition, and may give rise to ideas which are contrary to fact.... Locality is no more in the pin than pain is; of the former, as of the latter, it is true that "its being is to be perceived," and that its existence apart from a thinking mind is not conceivable.

The foregoing reasoning will be in no way affected, if instead of pricking the finger, the point of the pin rests gently against it so as to give rise merely to a tactile sensation. The tactile sensation is referred outwards to the point touched, and seems to exist there. But it is certain that it is not and cannot be there really, because the brain is the sole seat of consciousness; and, further, because evidence, as strong as that in favour of the sensation being in the finger, can be brought forward in support of propositions which are manifestly absurd. For example the hairs and nails are utterly devoid of sensibility, as every one knows. Nevertheless if the ends of the nails or hairs are touched, ever so [p. 314] lightly, we feel that they are touched, and the sensation seems to be situated in the nails or hairs. Nay, more, if a walking-stick, a yard long, is held firmly by the handle and the other end is touched, the tactile sensation, which is a state of our own consciousness, is unhesitatingly referred to the end of the stick, and yet no one will say that it is there.

Further in the essay we need not quote. Professor Huxley is swept along so vigorously by the Berkeleyan [Phenomenalist] argument, that in the end he admits with the good bishop that the primary qualities, just as much as the secondary, must be regarded as states of consciousness and hence, ultimately, if he had to choose between absolute materialism and absolute idealism, he would unhesitatingly adopt the latter. The corollary seems to be that he prefers to remain in the Newtonian [epistemological] dualism.

But now Huxley has offered us here the most plausible scientific argument that has to date been advanced in favour of that dualism, as regards the place it assigns to the mind. Descartes had insisted that secondary qualities must be stripped from extended matter, even pains must be taken out of our limbs, and all but the mathematical qualities bestowed on the soul, which operates from its seat in the pineal gland of the brain. Let us see what we can make of Huxley's defence of this position.

A pin pricks my finger, and I feel, as I say, pain in it. But Professor Huxley assures me that the pain cannot possibly be in the finger, and why? Because if the nerve fibres leading from the finger to the spinal cord are severed, I no longer feel the pinprick; therefore the sensation of pain must really be at the other end of those fibres namely in the brain. This strikes one at first sight as a curious argument; it is as if one were to say that since the cutting of the Croton aqueduct will cause the passage of water through New York City to cease, therefore the reservoir which we had supposed to exist in the lower Catskills must be really in the city. Furthermore, it can hardly be maintained that the nerve fibres do end in the brain. Normally, in such a situation, there is a continued nerve passage out from the cord or the brain and down through the arm to a muscle which pulls the finger away from the pin. [p. 315] Therefore, according to this way of arguing, the sensation of pain must be in that muscle. But no one as yet has been willing to maintain this. Do these considerations not suggest that if thinkers were not already convinced that feelings must occur in the brain, they would never have supposed that the notion was supported by such arguments?

But Professor Huxley calls our attention to some further facts. Sever the arm entirely, and prick the attenuated end of that same nerve fibre. Again the pain is felt in the same place, i.e., where the finger would have been. But nothing is there now but empty space, hence, triumphantly exclaims Professor Huxley, the pain certainly must be in the brain. But how in the world does this conclusion follow? Not to repeat the above remark, which would apply here also and require that the argument consistently applied would result in assigning the pain to some muscle of the arm, the facts are certainly widely sundered from the conclusion. It is obvious enough in this situation that the pain I feel and the pricking of the pin do not occur at the same place. But what has led us to fancy that we are resolving this problem by assigning the pain to some third place, namely the brain? I certainly do not feel it there. Other things happen there, as physiologists discover, but not the feeling. If we are to admit what is forced upon us by the simple facts, that the pain and the pricking are in different places, is it not by far the simplest and most consistent way out of the difficulty to hold that the pain is exactly where I feel it, even though to the eye nothing be there by emptiness? Surely no eye would have located it in the brain if he had not been antecedently convinced by some metaphysical prejudice that it must be there.

But the worst is yet to come. Let us adopt and make thoroughgoing Huxley's evident premise. Our sensations are all to be located where the nerve fibres leading from the various parts of the body affected terminate in the brain. Huxley observes, and correctly, that inasmuch as the nerve structure and the immediate perceptions are analogous in the case of all the senses, they are all subject to analogous reasoning at this point; hence, just as the pain felt must be in the brain, so the sound heard must be also in the brain. A step further we ourselves [p. 316] shall add, namely that the coloured and extended thing seen must be in the brain likewise. This is surely nothing but a consistent development of Professor Huxley's admissions and methods. The objects or contents of all the senses are alike concentrated at their proper nerve endings in the brain. But now, having pursued our premises to this result, what has become of the universe we perceive and suppose ourselves to live in? It is all contracted into a series of minute if not mathematical, points in the brain. But more still -in such an event what in the world can we mean by the brain? Where does it and the nerve fibres that lead into it exist? They too are known only by our various senses; they too must be nothing but minute points -in the same brain? No, that would be unintelligible nonsense -where? Well, stay a moment. After all, I never do perceive my own brain. So far as it is known directly and not merely inferred, it is something perceived by other people who may happen to be interested in investigating it. Therefore the whole of my perceived universe plus the brain in which it exists must be located in someone else's brain. And where does that brain exist? In some third brain, of course. Where now exist those last brains of people who perceive other brains but who are unfortunate enough to have no perceiver for theirs?

Surely we have somewhere run off the track of sane thinking. Is it because we have failed to distinguish between sensed qualities and characters of real objects to which they correspond, the former existing in the brain of the perceiver and the latter in the external world? But what can be meant by characters of real objects if they be something existentially quite different from sensed qualities? What can be meant by correspondence between the two? How can that correspondence be verified if only one term of the relation ever comes within the realm of perception? In practice we correct dubious perceptions by appealing to further perceptions; we never correct them by comparison with something unperceived. And, more challenging still, what can be the relation between the space of real objects and the space of perception? Both seem to be infinite and to contain all the room there is; even the space of perception seems to contain my body as a very small object [p. 317] within it. But on this theory the whole of it must be enclosed within my real brain. How vast a thing the latter must be! The greatest distance that I can measure by any sensible materials or tools must span only a small fraction of my own brain, for all such measurements are within the spatial world of my perception. Stranger still, the brains of other people seem to be very minute as compared with my own; they are but tiny portions of the perceived space all of which exists within my own brain. And on the same assumptions they make equally polite comparisons of my brain with theirs. Something must be off the track again. Or is the brain that I perceive in another man's head but an insignificant point within his own real brain? It is such a point within mine and mine is the same within his. What then is the spatial relation between his real brain and mine? Which includes the other, and why?

Those who combine realism with the Newtonian [subject-object] dualism have trouble enough on their hands working out consistent answers to the above questions. Sooner or later they are practically compelled to abandon the assumptions involved; the space of perception is too much like the space of real objects to reveal any essential difference from it. All it needs is to be freed from illusions, private images, and other experiences lacking social objectivity, to function quite acceptably as real space. And once this point has been reached there seems no longer any excuse for maintaining the distinction between sensed qualities and the real characters to which they correspond. In veridical perception they are located in the same area of space, and we never in fact attempt to find out what further imperceived things the ones we perceive correspond to. But this is the surrender of the dualism in anything like its Newtonian form. A radically different theory of mind is required to construe the situation in this fashion and to make the fundamental structure of scientific knowledge more than unintelligible nonsense.

The fact is, we can mean by real objects only two things. They are either an entirely transcendent and unknowable X, about which nothing more can be said beyond the bare mention of them; or else they are constancies of relation between groups of sensed qualities. In the latter case they are objects [p. 318] of experience, and the space in which they exist is essentially identical with the space of perception. In common life we all assume this, and take for granted the general validity of judgments of location based on our own spatial perception.

There is simply no science possible of the realm of sensible phenomena unless the trustworthiness of our immediate perception of spatial directions and relations be taken for granted. You think yourself justified in assigning my pain to the brain because you see what happens when the nerve fibres are cut, and you rightly assume that your vision is giving you a correct picture of what is going on in that portion of space occupied by those fibres. You are more than ever confident of it when other observers confirm you. This implies that the spatial world seen is the real spatial world, not something else. But why then should you turn around and accuse me of error when I say that the pain is in my finger? There is surely no logical impossibility in its being there, even in its being in otherwise empty space after my arm has been lopped off. The only people to whom it is an impossibility are those who already assume that the feeling must be in the brain, and if they were consistent they would acknowledge the seeing to be in the brain likewise -and where such reasoning ends we have just observed. Hence why, pray, is my feeling to be presumed a liar, and your vision always veracious? Why not admit that the feeling is where I feel it, inasmuch as you cannot avoid assuming that the seeing is where you see it? As long as I adhere to an empirical standard of truth, in fact, you shall be unable to convince me that something which I immediately feel is located in a different place from where I feel it. Empirically, there is no difference whatever between the senses in this respect. Through all of them we immediately experience things in various spatial relations, locations, or directions. There are doubtless important and interesting problems thrust upon us in the experiences Huxley cites, such as the matter of the nerve stump, of feeling with a cane, and the like, just as there are problems about visual illusions, but such problems can hardly be solved in either case by a total denial of the trustworthiness of the senses, but only by a more careful analysis of judgments which we pass on the basis of our sensible [p. 319] experiences. When I feel pain in a certain spatial locus, granted that the testimony of feeling is clear on the point, how can I empirically deny that I feel it there, even though to the eye that locus be some distance from the body? In that case I must simply affirm that the ordinary spatial correlation of the various senses does not obtain. Analogously, if I see a ghostly form where other people tell me there is nothing, or if I call objects green which they call red, still I can hardly deny that I see what I see, and in certain definite spatial relations with the other objects of my vision. In so far as I am a social being, however, I need also to get at a common spatial world which is verifiably there for all people; likewise, in order to live successfully I must get at an orderly, dependable world, and learn to distinguish clearly my purely individual and untrustworthy spatial experiences from those which make up that common dependable world. But to substitute for this thoroughly empirical process of the improvement and social correction of senses a speculative apriorism that flatly contradicts the immediate testimony of sense and places its objects in spatial relations wholly different from those in which they are sensed, can only lead, if carried out to its logical conclusion, to the complete confusion and mystification of science.

Philosophers since the days of Newton have gradually become cognizant of these considerations. But when it comes to the question of replacing this impossible doctrine by a positive theory of mind, there has been a radical diversity of opinion and a philosophy which will be fair to all the data and meet all the basic needs clamoring to guide their interpretation is yet to be invented. In general, it may be said that two main directions have been pursued. On the one hand there have been those eager to make mind itself, the knower of physical nature, an object of scientific study. To do this with exactitude and objectivity has meant breaking down the dualism by incorporating [p. 320] mind somehow into the world of bodily motions. On the other hand there have been those anxious to substantiate on a basis more acceptable in modern times the medieval accordance to mind of a high place and destiny in cosmic affairs. In general these two trends have been in violent conflict with each other.

To put ourselves briefly at the point of view of the former group, it does seem like strange perversity in these Newtonian scientists to further their own conquests of external nature by loading on mind everything refractory to exact mathematical handling and thus rendering the latter still more difficult to study scientifically than it has been before. Did it never cross their minds that sooner or later people would appear who craved verifiable knowledge about mind in the same way they craved it about physical events and who might reasonably curse their elder scientific brethren for buying easier success in their own enterprise by throwing extra handicaps in the way of their successors in social science? Apparently not; mind was to them a convenient receptacle for the refuse, the chips and whittlings of science, rather than a possible object of scientific knowledge.

To be sure, some thinkers in those days were willing to make ventures that might, if wisely and prophetically developed, have led in the direction of an objective science of mind. Outside of Hobbes' crude anticipations of behaviorism, Henry More's doctrine of the spatial extension of mind [(Spissitude)] is interesting to explore from this standpoint. More was willing to grant the [Reductive] materialists that everything really existing occupies space. Mind, too, then, is an occupant of space and has its own geometry, to be studied by comparable techniques to those by which the geometry of bodily motion is determined. Thus, seemingly, a verifiable science of mind might be worked out. Let us allow our fancy to wander along the routed that this speculation might indicate. "When I feel pain in my hand," a champion of this view would say, "resistance of the earth against my feet, and gaze at a glorious sunset beyond the hills -all at the same time- am I not extended in space? And if to these experiences be added a memory of some previous and more glorious sunset, together with an anticipation of the [p. 321] twilight soon to descend, am I not extended in time also? To be sure, there are important differences between my spatio-temporal extension and that of material bodies. The latter are regular, dependable, divisible into parts, and orderly, at least as regards their mathematical qualities and behaviour; the space and time which I occupy is a monstrous, irreducible unit, fluctuating rapidly and violently in size, shape, and centre of attention. But certainly my immediate experience through all the senses negates the notion that the difference between them and me lies in the fact that they are extended while I am not. Science depends entirely on the validity of my spatial perceptions of direction and relation -how in the world can they be either spatial or valid unless I am already an occupant of space? Indeed, can the bulk of modern thought be blamed for turning away from the more logically consistent form of Descartes' [interactive mind-body] dualism, which reached its grandest expression in [the Double-Aspect theory of] Spinoza, to a view which at least left some spatial locus for the soul, and offered a practical, though absurdly inconsistent, way of interpreting its relations with extended matter? For the relations exist. We know our spatial world, we live in it, enjoy it, use it. How could this be possible if we were absolutely unspatial ourselves? Can we clearly conceive anything as existing without occupying space and time, except a mathematical point?

"Now if the extension of the mind be thus demanded," he would continue, "where shall we limit that extension? We feel in every part of the body, nay perhaps beyond the body under certain conditions which ought to be analysed and determined. But can we confine ourselves to More's doctrine of the extension of spirit, which limits that extension to a thin effluvium surrounding the body? Are the things heard in the body, or the things seen no farther than the boundary of such a ghostly fringe? And how about memory and purpose? Is there any cogent reason to suppose that ideals and memory-images are in the present body at all? Have not the psychological and physiological difficulties about them arisen largely because we are determined to push them somehow into the brain? There is no help for it, we must declare unreservedly that a consistent empiricism cannot stop short of maintaining that [p. 322] the mind is extended in time and space throughout the whole realm that is spanned by its knowledge and contemplation. How else can the facts be expressed?"

But this outcome, of course, reveals how impossible it will be to make an exact science of mind by the aid of these conceptions. The mind thus studied is still an object of introspection, not of co-operative analysis; the space it occupies is a widely fluctuating unit, not determinable by any of the techniques of exact measurement which we apply to the objects of other sciences. No, this motive will lead clearly in the direction of identifying mind with activities of the organic body, which supply something objectively manipulable by accredited scientific methods and which are sufficiently correlated with mental events in the traditional sense so that the extent of the transformation is somewhat masked and the radical novelty of the doctrine minimized. When this is done with no qualification or reservation, psychology retaining no uniqueness but becoming a sheer branch of objective physiology, the outcome is behaviorism; when the same motives are dominant but qualitative uniquenesses of terms and relations are permitted to each science, a less extreme functional conception of mind results. Thus mind becomes an empirical object of co-operatively verifiable procedures, and the problem of the subjective as such, forfeited by a psychology which has thus crossed the Rubicon is handed over to philosophy.

Granted, however, the legitimacy of the motives which wish to render mind material for exact prediction and control after the fashion of objects of the other sciences -were the ancients and medievalists entirely astray in their doctrine that mind is in some sense a privileged and superior entity in face of the vastness of physical nature? Is there anything in the scientific situation itself which implies such a status for that which knows the world of science? Many philosophers have reacted to Newtonianism by elaborating affirmative answers to these questions. We may open consideration of their reflections by reminding ourselves of the rather suggestive fact that all schools of Greek thought, even the atomists, were agreed in assigning unique prerogatives and powers to mind; it may be that our modern hesitation to do so is due mainly to the abuse [p. 323] of such speculations by religionists eager to prove the immateriality and immortality of the soul. To be sure, since when we think and speak we are functioning as minds, it is well to be modest about our cosmic status, and if stressing certain truths about the wonder of mind is apt to encourage tender souls to bask in sweet dreams about their importance in the universe, perhaps these truths should not be stressed. None the less, there is a definite sense in which mind is the living perspective of the totality of human experience, the active and focal organization of the entire current of events and their meanings of which we humans become cognizant.

The whole vast realm which science reveals finds its rational order and meaning in the knowing activity of mind. So far from being a curious sensitive substance present in a small corner of the brain, or even an activity of the nervous system, mind seems to be a unique something to which the spatio-temporal realm, including the brain and the body, is or can be present. Or if objecting realists plead that the structure of meaning is as external to mind as physical nature, at least it must be admitted that mind is that something in the existential world most capable of actively participating in this realm of meaning. To note this circumstance and what it involves is not mere matter of silly self-congratulation. The so-called higher mental powers of human persons seem to be the completest perspectives of reality so far as revealed in our experience; as Aristotle insisted, they include all that other orders of being do and more besides. In their larger attainments reason, feeling, and purpose compose a marvellous unity of functions. When we see them at work in the smile and genial conversation of a friend we give free rein to our admiration and delight, whatever conscientious scruples seem to require when we come to philosophize. I had almost introduced the word "spirit" here, forgetting for a moment that at the sight of such a word sophisticated moderns would brand me at once a hopeless anachronism. Perhaps it might be well to surrender the old term mind to the mercies of behaviorists if we might recover in its place the term spirit from the fog of obscurantist mythology, and express by its aid such facts as these. Let the order of nature be ever so vast and all-absorbing -it is still but [p. 324] the object of rationally conceiving mind. And as for purpose, do we not empirically note that every object of mind is likewise a means for the realization of further ends? Among the irreducible relations of a thing known, is there not its relation to a more valuable end which it may be made to serve? If this be the case, then purpose [-i.e., final cause in the soft teleological sense of the term] is an even more ultimate function than knowledge and feeling, and mind, embracing by this term such knowing, appreciating, and purposive activity, must find its total explanation beyond the material world. Mind appears to be an irreducible [(emergent)] something that can know the world of extended matter, love ardently its order and beauty, and transform it continually in the light of a still more attractive and commanding good. Mind has the power to feel, to idealize, to recreate its world into something significantly better, as well as to know it.

Strange dualism between the theory and practice of us moderns -electrons are the only real things, but yet by applied science the world of electrons has been reduced as never before to a means for the achievement of ideal ends! The natural world after all is more the home and theatre of mind than its unseen tyrant, and man as expressing the functions of reason and spirit gathers to a focus far more of the flavour and creative fertility of the universe than the whole spatio-temporal object of his eager contemplation.

Mayhap [Perhaps] we must wait for the complete extinction of theological superstition before these things can be said without misunderstanding. Such is the misfortune of modern thought as compared with that of Greece. But in these two-sided considerations is bared the terrific difficulty of the modern problem of metaphysics. An adequate cosmology will only begin to be written when an adequate philosophy of mind has appeared, and such a philosophy of mind must provide full satisfaction both for the motives of the behaviorists who wish to make mind material for experimental manipulation and exact measurement, and for the motives of idealists who wish to see the startling difference between a universe without mind and a universe organized into a living and sensitive unity through mind properly accounted for. I hope some readers of these pages will catch glimmerings how this seemingly impossible [p. 325] reconciliation is to be brought about. For myself I must admit that, as yet, it is beyond me, and only insist that whatever may turn out to be the solution, an indispensable part of its foundation will be clear historical insight into the antecedents of our present thought-world. If the volume in hand has aided somewhat in the clarification of these it has fulfilled its modest pretensions.