and idealistic monism, and for the vindication of critical realism, the author relies exclusively on the application of the principle of causality to the content of our conscious states. In other words he is frankly representationist, denying to sense any intuitive, immediate grasp of any reality-whether self or non-self-beyond the flow of conscious states, and believing that he can vindicate for intellect the power of inferring validly, by the principle of causality, a real self and a real world of men and material things beyond consciousness. Similarly, whatever we can know of the nature of these realities we infer from what happens in consciousness-by the principle that the cause must be analogous to the effect and capable of accounting for its diversities and varieties. In chapters vii-ix, the validity of concepts is vindicated; the origin of all our knowledge through sensation is emphasized; the mediate and inferential character of all our knowledge is explained; and the difficulties raised in the first chapter are solved accordingly. Then follows a chapter on certitude and truth; after which two chapters are devoted to the Kantian theory of knowledge; and a closing chapter vindicates the possibility of science and philosophy. An adequate index enhances the value of the whole essay. We cannot help thinking that the vindication here offered of critical realism would not have been such plain sailing had the author kept in mind at an earlier stage the difficulties raised by Hume, and especially by Kant, against any and every attempt to transcend by knowledge the phenomena of consciousness. The principle of causality undoubtedly enables us to reach beyond the flow of individual conscious statesto a domain of being which we may call 'sub-' or 'supra-' or 'ultra-* conscious. Now, idealistic monism, or the modified form of solipsism which recognizes an ultra-conscious agent and subject of the panorama of conscious states, will admit as much. But how the principle of causality alone will interpret this domain for us as a real plurality of really distinct 'human persons' and 'material things' is not easy to see. Especially if, as the author emphatically asserts, all our concepts are abstracts of the immediate contents of sense consciousness; and if, as he asserts with equal emphasis, their immediate contents are all mental or mind-dependent 'appearances,' ' representations' or 'phenomena,' as opposed to mind-independent, existential realities; if, in other words, perceptionism or intuitionism cannot be in any form a true theory of sensation, if all sense awareness is necessarily and inevitably awareness of the mental contents of ever-flowing conscious states-how can the concepts of 'cause,' or 'agent,' or 'subject,' or 'substance,' validly reveal to us a plurality of real 'persons' and 'things'? The concept of 'something other than the flow of conscious states,' and the concept of something other than the real self' will, perhaps, serve our turn, if they can be shown to be valid concepts, i.e., to reveal real 'otherness.' But how can they be shown to reveal real otherness if the sense data from which they are abstracted-the sensuously felt 'otherness,' ' externality,' extensity,' 'successiveness, etc., of the contents of sense consciousness 6 -are characteristics of contents that are wholly intramental, and not of existential, mind-independent realities? If, on the other hand, our sense awareness does attain immediately to the extramental real, then those concepts can be validly used to interpret the nature of this reality, but the validity of our knowledge of its existence is vindicated by intellectual reflection on the process of sense perception, and without appealing to the principle of causality. The theory of immediate sense perception is, of course, not without its difficulties, but to us at least they do not appear at all so serious as those which confront representationism. Moreover, the former theory, as being more in harmony with men's spontaneous convictions-though quite distinct from 'naïf dogmatism '-should not, we think, without grave reasons, be abandoned in favour of an inferential realism which can be distinguished only by very close inspection from the 'symbolic' or 'transfigured' realism of Spencer, and which seems to accept the idealist postulate that our direct awareness cannot have for immediate object anything 'not existentially identical with my conscious states,' anything 'independent of my conscious states for its existence.' Yet Dr. Vance's essay may leave on the mind of the student the impression that the cause of realism is bound up with the theory of representative sense perception, and that perceptionism offers no defensible alternative way of vindicating the validity of our knowledge of a real, external universe of 'persons' and 'things.' That would be a regrettable and erroneous impression; and that the author has not sufficiently guarded against creating such an impression, even within the limits of what is an essay rather than an exhaustive treatise on the problems of knowledge, is the only defect we feel obliged to point out in an otherwise excellent and stimulating piece of sound philosophical analysis. The author is happy in describing the procedure whereby the extreme dogmatist tries to 'rush' his reader to conclusions by brushing aside difficulties-or refusing to regard them as worthy of serious discussion. After reading his own essay we could not avoid the thought that possibly a more mature reflection on the problem of 'transcending' the flow of conscious states, and vindicating the validity of the intellectual concepts by which this transcendence is ultimately justified, would convince the author that he, too, left by the wayside, on his onward march to certitude, some 'whys' and 'wherefores' which might have somewhat impeded his progress. But, then, it would be unfair to expect a discussion, or even a mention, of all of them within the limits of the volume he has given us. The author is right in devoting special attention to the Kantian theory of knowledge, and within the limits of two short chapters he has treated a difficult subject in a fair and satisfactory manner. The whole book is very readable which is a high encomium for a treatise on philosophy! This result is achieved by a fresh and breezy style, and by a tone that is conversational and confident. Indeed, the staid philosopher will probably grumble at its persuasive élan, and be scandalized at what he will possibly denounce as bordering on flippancy. But it is, perhaps, no harm to scandalize his sort. And it is certainly no small service to have published on a subject of the first importance a volume that may be read by all with pleasure and profit. A number of minor typographical errors escaped the notice of the proof-readers, but the book is turned out in a manner which, especially in war time, does credit to the publishers. P. COFFEY. SCIENCE ET PHILOSOPHIE. A. de Lapparent. Paris: Bloud et Cie. SCIENCE is a name to embolden the rash and to frighten the timid. For a number of years 'la science a été le grand cheval de bataille de l'incredulité. Tandis qu'à une autre époque on attaquait les dogmes au nom de la raison, aujourd'hui on les bat en brèche au nom de la science.' When one has pronounced this dread word it would seem that everything has been said and that there is no reply. But if we look this idol straight in the face we shall find it less formidable than it may appear at first sight. In truth, there is no such thing as Science, at least in the sense which the enemies of our faith attribute to the word. There are sciences, exact, physical, and natural. Mathematics are the art of reasoning under the most rigorous and most precise form, and are to sciences what the syllogism and logic are to psychology. They furnish not the least argument for or against philosophic theories. The question then is limited to natural and physical sciences. There are three notions suggested by the study of these sciences: order, the expression of supreme intelligence; force, general and permanent, the symbol of omnipotence; and continual change, the premonition of a determined end. No matter how incredulity may interpret these magnificent teachings we cannot but regard them with the same pious sentiments and enthusiasm that animated Kepler, who, seeing his calculations at last confirmed by observation, uttered not a cry of pride or of blasphemy, but a hymn in praise of the Sovereign Creator of so many wonders. Why, then, it may be permitted to ask, does modern education draw such a hard and fast line between literary and scientific teaching? In France philosophy is separated from the sciences, in these countries the sciences are separated from the classics. In a splendid little book on Science and Education edited by Sir Ray Lankester, in one of the lectures Dr. Whewell writes: "I wish to show that this influence (of Scientific Discovery on Intellectual Education) has been so great that its results constitute, at this day, the whole of our intellectual education:-that in virtue of this influence, intellectual education has been, for those who avail themselves of the means which time has accumulated, progressive; that our intellectual education now, to be worthy of the time, ought to include in its compass elements contributed to it in every one of the great epochs of mental energy which the world has seen.' He recommends the study of the natural sciences, because they supply a remedy for some of the evils which, along with great advantages, may result from the study of Logic, at present extensively employed as an element of a liberal education. 'The examples of reasoning given in books of Logic are generally so trifling as to seem a mockery of truth-seeking, and so monotonous as to seem idle variations of the same theme. But in the History of Science we see the infinite variety of nature; of mental no less than bodily nature; of the intellectual as well as of the sensible world.... The history of science may do, and carefully studied must do, much to promote that due apprehension and appreciation of inductive discovery; and inductive discovery, now that the process has been going on with immense vigour in the nations of Europe for the last three hundred years, ought, we venture to say, to form a distinct and prominent part of the intellectual education of the youth of these nations.' M. de Lapparent states more specifically the advantages to be derived from a study of the natural sciences: 'Ces dernières (sciences naturelles) ont le grand avantage de nous rapprocher d'un monde extérieur que l'existence des villes tendrait à nous faire oublier de plus en plus. J'insiste là-dessus, car on ne se figure pas assez combien la vie que nous menons dans nos grandes cités est artificielle et séparée de la nature. Dieu ne nous a pas mis au milieu d'une si magnifique création pour nous permettre d'oublier ce monde dont il nous a faits les rois. Les sciences, loin de dessécher le cœur et l'intelligence, les dilatent au contraire en les fortifiant. Quand l'étude de la nature n'y est pas séparée de celle des formes abstraites du raisonnement, l'esprit en reçoit une précision sans roideur, en même temps qu'il y acquiert une méthode et une logique incontestables. Enfin, par le contact intime et raisonné qu'elles établissent entre l'homme et cette création si admirable jusque dans ses moindres details, elles eveillent en nous comme un écho lontain, ou mieux, comme un avant-goût de ces harmonies supérieures aux-quelles tout nous dit que nous serons un jour conviés.' . ... In M. de Lapparent we have a magnificent type of the lay Catholic, of a man of faith, of philosophy and of science. His appeal is telling, he holds his readers from beginning to end, not only because of his apparent sincerity, but because of his precision, his impartiality, his sound scientific learning, and his philosophic methods. He passes in review the philosophic teachings of science and shows that they supply 'un renfort intellectuel à tous les motifs que nous avons déja de nous incliner devant les enseignements de la foi.... La science doit donc nous apparaître comme une récompense que Dieu réservait à l'homme pour prix de son labeur quo tidien.' There are those, on the other hand, 'conduits par la haine et les préjugés, pour qui la science est une arme de parti et chacune de ses conquêtes une occasion d'arracher une nouvelle pierre à un edifice dont ils ont juré la perte.' They pretend to erect on a scientifically indisputable basis a new society. The question then arises: 'Quelle certitude présentent leurs dogmes.' The author then reviews the principal branches of human knowledge to see to what degree of certitude each of them can legitimately aspire in the matter of doctrine. He discusses palæontology, geology, mineralology, mathematical physics. He examines crystallography and shows that crystals which appear so simple are, with the aid of optical instruments, 'des édifices d'une grande complication; de telle sorte que les lois posées par les fondateurs de la science se réduiraient à n'être plus que les lois élémentaires. Mais bientôt se produit une nouvelle surprise! Cette symétrie que nous admirons, ces formes géométriques souvent si parfaites des cristaux sont, la plupart du temps, ce qu'on pourrait appeler une tricherie de la nature.' In a similar manner he examines the theories of light and heat, shows that the conception of ether even implies a contradiction, 'Ce corps, si subtil que nous ne pouvons ni le voir, ni le toucher, ni le peser, et qui, neanmoins, est par excellence un corps élastique.' To get rid of the difficulties of ether some physicists 'proposent de substituer l'hypothèse d'une force partout répandue à celle d'une matière imponderable universelle. Comme si ce n'était pas tomber d'une difficulte dans un autre que de concevoir des moteurs sans mobiles et d'imaginer un système où il n'y aurait plus que des puissances, sans elements passifs. Concluons donc qu'autant les sciences physiques ont réalisé, dans le domaine des faits, d'admirables progrès, autant l'edifice doctrinal et philosophique en est encore incertaint et chancelant. Plus on y regarde de près et plus les doutes grandissent.' Let the savant pursue in the calm of the laboratory his patient investigations, let him reveal the secrets of nature, let him bring under control the forces of nature, in order to use them for the amelioration of man's lot here below. In that, he will merit the esteem and gratitude of the world, for he will have accomplished a healthy work, absolutely conformable to the great law of work. At the same time he will furnish a useful counterbalance to certain excesses of idealism or of human mysticism in which may go astray minds that do not hold sufficient communion with nature and reality. 'Mais qu'on sache reconnaître avec franchise à quel point l'œuvre philosophique de la sciènce est encore imparfaite, et combien elle est éloignée de nous donner la clef d'aucun des problèmes qui préoccupent si justement nos âmes.' The coral islands with their blue lagoon, and their 'state of nature' in all its plenitude, have furnished the novelist with a fascinating background for his playful fancies, but they furnish the scientist with much more important material for scientific theories. Darwin formulated the theory that in these regions the bed of the ocean had sunk gradually, leaving on the surface the accumulation of the coral polypus that built a fringe around the islands, and above them, as the islands gradually subsided. Considering the depth and thickness and extent of these coral reefs and the slow process of formation, Darwin's theory was to push back the age of the earth beyond what geologists until then admitted. M. de Lapparent gives a very complete and fascinating account of the whole subject, the voyages of Wilkes and the experiments of Dana and Murray. He shows that there is question here not of the subsiding but of the raising up of the bed of the ocean, and that the atolls of the Pacific are always situated on volcanic cones. The whole episode goes to show how plausible theories that have gripped the minds of scientists may be shaken in the onward march of science. The same important fact is evident in the great discovery by Huxley of the Bathybius, a gelatinous organism, the most elementary of protoplasms found in the bed of the Atlantic. After many years of voyage and discovery, after much jubilation over this wonderful discovery of the most elementary form of life, and |