Popular Science Monthly/Volume 59/August 1901/Science and Philosophy
|SCIENCE AND PHILOSOPHY.|
UNIVERSITY OF MICHIGAN.
WHETHER the average man recognize the situation or palter with it, there can be no doubt that a dualism, a separation, if not an antagonism, between science and religion forms one conspicuous phenomenon of modern life. True, palliating circumstances may have eased or disguised it somewhat in recent years. But palliation was always a makeshift, and, everything considered, the fundamental opposition remains, little mitigated. Of course, we may allege that religion and theology are by no means identical, and that the latter rather than the former withstands scientific views and conclusions. Yet, when we summon courage to be quite frank with ourselves, we must admit freely that religion, as an organized social factor, is so bound up with theological presuppositions as to render this distinction more of a subterfuge than a solution. Again, many in these days seem to think that another marked contrariety of interest characterizes the relation between science and philosophy. And, indeed, one must admit that, altogether apart from theoretical problems, certain features of the academic world, in such countries as Scotland and the United States, for example, afford basis for this prevalent opinion. In the Scottish universities one-half of the professors of philosophy are clergymen. In the universities and colleges of the United States the theological affiliations are even more intimate. Speaking from memory, I recall that in only three of our nine leading universities do we find the philosophical departments free from clerical influence, while, in the lesser institutions, clerical control constitutes the rule, not the exception. Small wonder, then, if many have identified the tendencies of philosophy with the theological, as opposed to the scientific, side of contemporary controversy.
But, if manifold causes thus support the view that science and philosophy must necessarily conflict, there happen to be other aspects of the matter well worth consideration. In Germany, for instance, the home land of philosophical inquiry during the nineteenth century, the progress of science has been exercising decisive influence on speculative thought for a generation at least. Furthermore, the rise and development of experimental psychology has induced many, whose main work lies on the philosophical rather than on the scientific side of the fence, to familiarize themselves with the scientific attitude and temper, while the gradual entry of the sciences into the usual undergraduate course at our colleges has not left the earlier education of those who come afterwards to specialize in philosophy so utterly void of scientific knowledge as it used to be. Moreover, the long commerce of our ablest students with German culture cannot but have produced similar modifications. Be this as it may, the point I desire to emphasize is that no conflict can exist properly between science and philosophy, and that a most interesting—possibly the most hopeful—trait of recent thought may be traced precisely in the inclination towards an alliance. It ought to be said, too, that some few, whose work appears to lie in the immediate future—to present symptoms of decided vitality—tend clearly in this direction. And, when we stay to reflect for a moment, why should it not be so? Science and philosophy possess this in common—they search for the truth free from all trammels of dogmatic presupposition. If they prove true to themselves, their object must be the same, even if they view it from different sides and for different purposes. Take them from what standpoint you please, both are 'science' in the broad sense of the untranslatable term, Wissenschaft. It may be of interest, therefore, to devote some attention to the new-old question. What is the relation between science and philosophy?
Approaching the problem historically, it proves something of a shock to learn that the so-called opposition had no existence seventy years ago. Nay, from the time of Descartes' 'Discours de la Methode' (1637) till the enunciation of the cellular theory (Schleiden and Schwann, c. 1838), free interaction, often conscious cooperation, prevailed. Eecall the full title of Descartes' epoch-making tractate, 'Discours de la Methode pour bien conduires sa raison, et chercher la verite dans les sciences; plus la Dioptrique, les Meteores et la Geometric, qui sont des Essais de cette Methode'; recall Spinoza, the optician; recall Leibnitz and his calculus; recall the sober, scientific temper of the entire British school, from Hobbes to Hume; recall Kant's cosmogony, the precursor of modern ethereal physics, and remember that the critical philosopher likened himself, not to Plato or Bacon, but to Copernicus; you find no ground for controversy, but every symptom of mutual good-will. The contrast between this two hundred years' truce, covering the history of thought from the Reformation till the French Revolution, and the undignified, profitless squabbles, still fresh in the memory of many middle-aged men, is so striking that a call for reasons goes forth at once. If this matter can be elucidated, much will have been done to explain away the recent unfriendliness. At the same time, the case presents peculiar difficulties, because the evolution of thought in this connection furnishes one among the great paradoxes of history. Ever fond of revenges, the Time-spirit becomes supremely ironical here.
Post-Reformation Europe accomplished much for science and philosophy. In both fields, investigation followed clearly marked lines, but the conclusions reached were of such a nature that they dovetailed easily. For science meant the mathematico-physical sciences, specifically, mathematics, astronomy and 'molar' physics. Philosophy meant, on the continent, the metaphysics of dualism, starting from the question, How can matter and mind, extension and thought, as they were then termed, be related so as to form a consistent whole; in Britain, individualistic psychology, concentrated on the problem. How do I get knowledge, and, when obtained, what is it? In a word, the sciences and philosophy attacked the same universe—the universe as conceived by Newton. Philosophy did not aspire to a higher knowledge than that reached by science, but confined its inquiries to some aspects of the world which had been left untouched by mathematics and physics. Thus both arrived at consonant conclusions. Harvey, for example, did not suggest that Bacon wrote on scientific questions like a philosopher, as he would assuredly have done had they lived forty years ago; he said merely, the Lord Chancellor writes like a Lord Chancellor—a lawyer of assured position.
The general view of the universe then held by scientific men supplied the framework within which the philosophers labored; it did not occur to the metaphysicians that the modes of thought in which this universe was conceived could be subjected to fundamental criticism. What, next, was this view? Briefly, it may be called static, molar and mechanical in the strictest sense of the word mechanism. It dealt with self-contained bodies in equilibrium or at rest; with self-contained aggregations of matter capable of measurement; with the relations subsisting between self-contained wholes; that is, with external connection, not with internal self-manifestation. As time passed, this general conception of things became more and more firmly rooted, thanks to Newton's genius. Indeed, it maintained itself with little change, especially in the English-speaking countries and in France, till forty-five years of the nineteenth century had winged their way. Whewell, in his great 'History of the Inductive Sciences' (1837-57), displays astonishing ignorance of the transformations that were afoot in his day—of Gauss and Weber on absolute measurements, of Schwann on the cell theory, of Mohl on protoplasm, of Mayer on heat, of Helmholtz on the conservation of energy, of Herapath on the mechanical theory of gases and the like. If the hold of the 'Newtonian philosophy' remained so strong at this date, we can infer readily how exclusive was its predominance in previous times. Now the theory of the universe contained in the Principia had a distinctively philosophical aspect in so far as it was universal. Otherwise it presents few qualities to which we should attach this name at present. For the system contemplated the division of matter into separate parts, each of which occupied a place—a place subject to change, no doubt—in empty space, while to these circling orbs force was linked somehow. The relation between any two, therefore, can not be the result of inherent nature, but must follow from the interference of a cause external to the terms of the relation. Newton has put himself on decided record on this very question. In a letter to Bentley, written about the new year of 1693, he says: "It is inconceivable that inanimate brute matter should, without the mediation of something else, which is not material, operate upon and effect other matter without mutual contact, as it must be, if gravitation, in the sense of Epicurus, be essential and inherent in it. And this is one reason why I desired you would not ascribe innate gravity to me. That gravity should be innate, inherent and essential to matter, so that one body may act upon another at a distance through a vacuum, without the mediation of anything else, by and through which their action and force may be conveyed from one to the other, is to me so great an absurdity that I believe no man, who has in philosophical matters a competent faculty of thinking, can ever fall into it. Gravity must be caused by an agent acting constantly according to certain laws; but whether this agent be material or immaterial, I have left to the consideration of my readers." Summarily put, this means that the solar system is the type of universe, and it is a system, because 'an agent acting constantly according to certain laws' has rendered it such. And this implies, further, that, while a description of the universe may be possible, as in terms of mathematics, an explanation of it is beyond reach.
Turning to the philosophical side, a curious parallelism attracts notice at once. Of course, we are dealing no longer with 'heavenly bodies,' but matter and mind are treated by the philosophers exactly as Newton dealt with his material wholes. Descartes asks himself in effect. How is it that thought, which possesses none of the qualities of extension (matter) and extension, which possesses none of the qualities of thought, comes to unite so as to be a single whole in man's experience? He supposes that ideas are copies of things. But, even so. How do we know that the copies are correct or reasonably adequate? The solution can come by one answer alone. Some agent, which is neither an idea nor a thing, must vouch for the correspondence. Just as, in the physical world, one body can not affect another, except by the operation of a law-giving agent, so thought and extension can not be combined in our universe, except God have so willed it. The parallelism is precise. A 'third thing,' belonging neither to the sphere of intellect nor to that of the external world, must be assumed as the basis of both. Here we meet that hoary sinner, the 'uncaused cause' about which, to our modern amazement, the science and philosophy of that day are agreed entirely.
Passing to England, we find Locke confronted by a different problem, but the setting remains identical. Assuming, like Newton and Descartes, two separate factors—others assumed many, but the number makes no essential difference—and asking. How do I, who am inside, get my knowledge of things, which are outside? Under the circumstances, the obvious reply is, through the senses. The senses write upon the mind. Unfortunately, this information about the external world lacks directness, for the senses are modifications of the bodily organism and therefore tell nothing about the real objects. How, then, placed in such a dilemma, do we know objects? Locke alleges that Substance, a thing which we do not perceive, but which we are compelled to infer, originates the conviction of permanence associated with reality in objects. Here, once more, a third thing, belonging to neither of the factors under review, plays the part of Newton's agent and of the Cartesian deity. Without condescending upon further details, it is easy to see why science and philosophy could not well fall out during the period when such conceptions held sway. But this agreement, happy in its unconsciousness of problems at all events, was not to endure forever. The world of human experience revealed new aspects, and fresh questions, sources of dire controversy, loomed upon the horizon. The dynamic, molecular and organic modes of thought, with their attendant conception of the universe, were destined to elbow out the static and mechanical.
Even amid many seeming transformations, the 'Newtonian philosophy preserved itself unchanged in essentials. The Deistic movement, Butler's 'Analogy,' Pope's 'Essay on Man' and Paley's 'Natural Theology,' and the highly wrought productions of the great French physicists, culminating in Laplace's 'Mécanique Céleste,' even the Scottish 'common-sense' protest against current scepticism, all emerged on the basis of its first principles. But, after the middle of the eighteenth century, three men shook it to its foundations and made possible the new structure we now call 'modern' thought. These men were Hume, Kant and Herder; the half-conscious protest of Spinoza had passed over the heads of his contemporaries unheeded. Was he not a Jew, a pantheist and, therefore, a flat blasphemer? The joint performance of this eighteenth century trinity, 'equal in power and glory,' raises problems of the most complicated kind, so complicated, indeed, that they have been the bugbear even of expert students during the last two generations. I can attempt here to put the salient points only, as clearly as possible.
Many pious efforts to understand Hume have been frustrated by the idea that he was a dangerous sceptic, an infidel, a bold, bad man and what not. The simple truth happens to be that Hume found himself confronted by certain definite questions which had grown under the hands of his predecessors. In his case, the power of the man coincided with the power of the moment; and he still occupies his lonely pedestal as the single thinker of the first-class produced by the Anglo-Saxon race, because he settled the account of an age once for all. Had this been comprehended sooner, the nineteenth century would have been saved a wealth of waste paper and some lost temper. Reduced to its simplest elements, Hume's central problem is by no means hard to grasp, particularly if the Descartes-Newton scheme be recalled. Granted that separation of individuals, whether of men, of material bodies or of thought and extension, constitutes the fundamental fact in the universe; granted, too, that knowledge flows into consciousness through the senses, then what value can be attached legitimately to human experience? Hume, as one must always remember, possessed the wit not to rest satisfied with the dogmas that appeased his forefathers after the intellect. He wanted to know what precise inferences could be extracted from their cherished opinions, and he suspected that their satisfaction had not been won fairly. Accordingly, he showed, and the proof holds good beyond peradventure, that, on this traditional basis, human knowledge can be viewed only as a huge delusion. Objects, self and deity; matter, mind and cause; science and philosophy engulf themselves. Another alternative is impracticable, if the presuppositions, common to the mathematico-physical sciences, to the Cartesian metaphysics and to the British psychology, be admitted. It was no part of Hume's task to examine this foundation. He accepted it without change as it came to him and proved, in the most thoroughgoing fashion, that universal nescience was its sole logical end. Dualism, self-contained bodies, sensationalism, 'an agent acting constantly according to certain laws'—in short, the entire paraphernalia held conjointly by the science and philosophy of the seventeenth and eighteenth centuries, he hoisted with its own petard and blew to shivers irretrievably. For, admit his premises and the conclusion follows resistlessly. Now, the view of the universe prevalent from Descartes to Paley, from Galileo to Laplace, depended on Hume's premises and upon nothing else! So ended the first lesson, like its kind, not to be taken to heart for many a long day.
If the real implications of Hume's argument remained hidden from science, thanks to the continued predominance of the 'Newtonian philosophy,' and from the men who spoke Hume's tongue, thanks to contemporary political and theological causes, the same cannot be said of Kant. His philosophy took Europe by storm and has continued to influence scientific men perhaps more than any other body of philosophical thought. His contribution to our present subject of inquiry consisted of two parts: (a) the distinction between Verstand and Vernunft, (b) the conclusions gained in the last division of his masterpiece, the 'Critique of Pure Reason.' The former was destined to exercise decisive effect on the relation between science and philosophy; the latter, as I understand the 'Dialectic' met much the same fate as Hume's destructive analysis—it was misinterpreted or overlooked. We may therefore take it first, and very briefly. In the third part of the 'Critique of Pure Reason,' entitled 'Dialectic,' because it deals with subjects capable of dialectical treatment, Kant shows that the metaphysic of his predecessors must be adjudged a complete failure. Mathematics and physics exist, for they have objects; but metaphysics has no existence, its objects are unthinkable, humanly speaking. Take the soul (or self) as a self-contained thing, occupying a place among the other self-contained elements of human life; interpret the universe as a self-contained object, one among other objects of experience; conceive God as a self-contained 'agent acting constantly according to certain laws,' and residing far out in the depths of space; in a word, let your fundamental conceptions be those of the Descartes-Newton type; then, when you come to analyze them, you will find of a surety that no such soul or universe or God can possibly enter into human experience. This Kant proves, and so cuts the throat of the metaphysic which ruled science and philosophy from the Reformation till his day. On the whole, philosophers have not yet fathomed his meaning, while scientific men have been quick to seize his point, that metaphysic does not exist, forgetting completely that his work was preliminary to the necessary question: What, then, are soul, the universe and God? To declare, with a certain quasi-scientific school, that these are mere ideas, helps us not a whit. For the declaration, as they do not see, destroys the validity of science also. Thus, on a broad view, we have still to reckon with this aspect of Kant's thought.
The distinction between Verstand (understanding) and Vernunft (reason)—the English words fail to translate, unfortunately—stands in very different case, having been productive of momentous consequences. Kant's early scientific researches led him to see that a dynamical account of the material universe ought to be substituted for the static conception of Newton. Indeed, he hit upon the idea of preorganic evolution; but, as thermodynamics lay in the future, experimental evidence lacked, and he was switched on to another line by Hume. According to Hume, knowledge is phenomenal, and phenomenal only. It consists of what assumption, that knowledge comes from the senses, did not suffice to explain experience. Man's mind is endowed with certain forms or principles of synthesis, by means of which the sense-material is organized into knowledge. Vernunft is the faculty whereby such principles may be apprehended. It implies a higher range and a deeper insight than Verstand. This superior faculty, in combination with an amplified reading of Herder's theory of historical evolution, was to be responsible for much, as we shall see in the sequel.to be; can have no commerce with what is. By analysis, the most complex ideas can be proved to possess a phenomenal basis. The faculty of analysis, which deals thus with phenomena, Kant called Verstand. But he insisted that Hume's
Herder, a younger contemporary of Kant, turned away from the mathematico-physical sciences, to which nearly all great intellects had been attracted for two centuries, and entered enthusiastically upon the study of the history of culture, of culture in the spacious sense of civilization. Even in this line of research, he can not be called an exact student. But his was a vitalizing personality, and so, his limitations notwithstanding, he originated the evolutionary and organic idea which may be termed appropriately the nineteenth century standpoint. He took particular delight in poetry, religion, language and the like. As early as 1767, he enunciated the conception which was to create historical science. "There is the same law of change in all mankind and in every individual, nation and tribe. From the bad to the good, from the good to the better and best, from the best to the less good, from the less good to the bad—this is the circle of all things. So it is with art and science; they grow, blossom, ripen and decay. So it is with language also." In the realm of the human spirit, all things work together; "history leads us into the council of fate, teaches us the eternal laws of human nature and assigns us our own place in that great organism in which reason and goodness. . . must create order."
At this point we strike the psychological moment when the conditions that led to the conflict between science and philosophy were assembling. Evidently, the center of gravity of philosophical inquiry would be shifted from the old mathematico-physical parallelism, if a professed philosopher were to appear equipped with the insight and speculative daring requisite to unite Kant's conception of Vernunft with Herder's fruitful suggestion, that history is a vast organism 'in which reason must create order.' This epoch-making thinker did arise, in the person of Hegel. We can not stay to outline the Hegelian system, but must rest content to state its germinal idea. Following upon Herder's pregnant thought, Hegel conceived of the universe as a single unity, inspired and controlled by a principle of reason, a principle in and through and for which everything has being. Obviously, if the human mind can grasp such a principle, Kant's faculty of Vernunft is the one power endowed with the necessary ability. As obviously, on these conditions, if a thinker can pick out, as it were, the rational forms under which this principle manifests itself, he will have mastered the mystery of all things. From the year 1818, the date of Hegel's election to the chair of philosophy in the University of Berlin, till the break-up of his school, about 1850, his thought dominated the intellect of Germany to a degree unparalleled, and from 1865 till the present time, it has wielded power in the British and, to a lesser extent, in the American universities. The reason for this is patent. No other thinker entertained modern views. In the English-speaking countries particularly, men faced the past, not the future. Hegel, on the contrary, whatever may be said in his despite, had carried the dynamic, organic and evolutionary explanation into every corner of the humanistic realm. Nevertheless, he and his disciples must bear the chief responsibility for the estrangement between science and philosophy throughout forty years (1850-90) of the nineteenth century. Why?
In the first place, this, the most influential system of modern philosophy, had been completed to all intents and purposes by the year 1816. And, unfortunately, this statement implies another. In 1816, modern science was as yet unborn. Of course, one does not forget the work of Haller, at Göttingen; of Cuvier and Bichat; of Treviranus, who was the first to use the term 'biology,' in 1802; and, above all, one calls to mind Charles Bell's capital discovery, in 1811. Still, all these died in the faith, they having received not the promises. In France, mathematical science maintained its glorious history, thanks partly to the favor of Napoleon. In Germany, the rule of the modern scientific spirit dates from 1826, with the foundation of Liebig's laboratory at Giessen. In Britain, all the great advances. Bell's excepted, fall within the domain of astronomy, physics and the older chemistry. Yet, despite this meager knowledge, as we deem it now, of the intricacies of nature, a thinker dared to present an absolute philosophy—a key to all the mysteries.
In the second place, the interpretation of Hegel's system by his followers, if not its elaboration by himself, had become increasingly formal, perhaps abstract, just at the moment when science was making some of its most astonishing discoveries. Small wonder, then, that investigators of nature, successful beyond all precedent, turned in contempt from a philosophy which seemed to them, rightly or wrongly, a species of revived scholasticism. Moreover, the bitter attacks on Hegel emanating from workers on the philosophical side, like Herbart and his pupils, who appeared to be, and possibly were, sympathetic with scientific methods, served to deepen this impression. By 1865, when the cry, 'Back to Kant!' had taken effective possession of many and was emphasizing the importance, for science, of a certain interpretation of Kant's thought, this antagonism crystallized finally.
Lastly, Hegel's 'Naturphilosophie,' containing his account of those phenomena of nature to which he attempts to apply his principles, was the weakest spot in his system. As the sciences progressed, this became more and more evident, and it would have been asking too much of human nature to have required the enemy to forego this grand opportunity for telling assault. No doubt, these attacks went too far, as the formative influence of the 'Philosophy of Nature' upon men like Oken, Oersted, K. E. von Baer, Johannes Müller and Schönlein proves overwhelmingly. Nevertheless, the fact remains that the insights of 'Naturphilosophie' were not restored to scientific citizenship till late in the century, and its unchastened speculations alone attracted general attention in pre-Darwinian times. In this field, the decisive one for science, be it remembered, the vaunted higher and special knowledge of philosophy was adjudged guilty of ludicrous error, of gross carelessness, of otiose imaginings.
While the newer science thus scouted the new philosophy, was it without sin? In answering this question, we come upon what I have called one of the greatest paradoxes of history. Just after the nineteenth century had passed its zenith, a group of writers, penetrated by the dynamical and biological tendencies of contemporary science, thought that the times were ripe for an accordant theory of the universe. The discoveries of Wöhler, who produced an organic substance by the synthesis of inorganic materials; the startling advances of biology, especially in the physiological line; and the speculations of such thinkers as Schopenhauer and Feuerbach, appeared to furnish a ground for scientific explanation of certain factors in experience which had defied interpretation hitherto. Thus, despite its contempt for the regnant philosophy, science, stimulated by its own problems, produced a philosophical theory. Opponents of this movement, like opponents in all ages, thought to get rid of an irritating novelty by means of a nickname. Accordingly, we hear of the monism of Moleschott, Büchner, Carl Vogt and Haeckel. By applying this title, critics intended to indicate that these thinkers suppressed the great differences of experience—the difference between matter and mind or between the organic and the inorganic—and saddled one term, in this case, matter or the inorganic, with the entire responsibility of a solution. Now, it is true that this school alleged matter to be the cause of mind, that they said, 'brain secretes thought as the liver secretes bile,' and did many other things equally foolish or objectionable. At the same time, their critics stood too near them and a clearly defined focus was unobtainable. The real fact was—and here the paradox emerges—that Büchner and the rest set up, not a monism, but a dogmatism. Despite the circumstance that the progress of science, to say nothing of Hume and Kant, had demonstrated beyond doubt the insufficiency and fallacy of the dualistic, static and analytic theory of the universe, they accepted this as a presupposition. To begin with, matter and mind were not one, but two; they were different, that is. Given this difference, then, how explain them? By showing that, in the time series, mind came second, and was therefore caused by matter. The laughable paradox is that men steeped in the biological view, which utterly overturns this mechanical externality, adopted the latter as the means adequate to account for the former! Of course, a man may do this, if he please, but at his peril. For, Hume and Kant and the biological sciences have combined to show that, even before it could be stated, this doctrine had become, not merely untenable, but positively unthinkable. It was now the philosophers' turn to blaspheme their brethren of science. If the errors of 'Naturphilosophie' had handed speculative thought over to the tender mercies of exact science, the ludicrous obtuseness of the so-called materialists respecting what was possible in philosophy brought the thinkers their due revenge. Thus the dispute became interminable and the Jew had no dealings with the Samaritan. For science, philosophy appeared so much vague or formal speculation; for philosophy, science, in so far as it tried to explain the world, seemed nothing but a blind blundering among exploded errors peculiar to Locke and the French encyclopedists. Despite Lotze's effort at mediation, too complacent towards both parties to command the respect of either, this was the substantial situation from 1850 till 1885. And, when we hear to-day of the opposition between science and philosophy, our ears are really ringing with echoes from the period of the great paradox. The later developments of physics, chemistry, biology and psychology have brought scientific men to a point where they can see that the mere adoption of the 'Newtonian philosophy,' minus the 'agent acting constantly according to certain laws,' is a far too simple solution of the obscure problems on hand. Seductive it may be, it fails notoriously to fill the bill. Similarly, philosophers begin to understand that Hegelianism must go as a system, even though they feel that they must retain Hegel's one contribution to progress—the principle that experience can be explained, if at all, only by reference to itself. Also they evince symptoms of perceiving that the watchword, 'Back to Kant!' valuable enough in 1860, must be replaced by the new rallying cry, 'Forward from Kant.' The critical philosophy cleared a site upon which it is possible and proper for science and speculation to cooperate in building now.
Science and philosophy may easily return to the old footing, then, if they will but have a mind to rid themselves of the peculiar dogmas that have afflicted each during the last century. This implies mutual self-sacrifice, but sacrifice of the unimportant, very likely of the harmful. There is no good ground for the belief that with the circle of the positive sciences knowledge ends; for the naïve supposition that an object can exist without a subject; for the marvelous delusion that observation and experiment are capable of revealing things new and old without the aid of mental synthesis or of psychological volition; for the charming inconsequence that we perceive phenomena and are therefore ignorant of reality. But equally, no basis can be found for the idea that philosophy has means of access to some special knowledge denied science; that one can afford to neglect science in favor of rational forms; that the conclusions of physics, chemistry and biology are subject to revision at a higher tribunal; or that the work of the sciences is a monstrous delusion. On the contrary, there is every reason for insisting that science and philosophy are interwined inextricably—much more inextricably now than they could have been in Newton's time. Both work upon the same closed universe. This is the important fact, even if science inquires, What is it? philosophy. What does it mean? Nay, both questions are unanswerable, and so the two disciplines alike end in approximation and hypothesis. As Eomanes has put it, "The 'Origin of Species' first clearly revealed to naturalists as a class that it was the duty of their science to take as its motto what is really the motto of natural science in general, 'Felix qui potuit rerum cognoscere causas,' not facts, then, or phenomena, but causes or principles are the ultimate objects of scientific quest." They are the objects of philosophical quest also, as Romanes shows elsewhere. In a word, to become conscious of its own fundamental principles, science must transform itself into a kind of philosophy, while to become acquainted with its own illustrative material, philosophy must transform itself into a kind of science. This way lie harmony and progress. We expect the twentieth century to furnish forth the imperative eirenicon. It can not come too soon.