EXPLANATORY. The Appendix on Insurance has to be omitted in the present number, on account of the sudden illness of the writer. This is the first time that omission has been made in eight years, and it is hoped that it will not occur again for as many years to come. The editor is quite aware that there are many-indeed all that are criticised-who would be glad if the Appendix were omitted. But no honest underwriter would; and there is ample proof that the general public scarcely read any article in the Review with more avidity than the Appendix on In surance. THE NATIONAL QUARTERLY REVIEW. No. L. SEPTEMBER, 1872. ART. I.-1. Essai sur l'origine des connaissances humaines. Par L'ABBÉ ETIENNE BONNOT DE CONDILLAC. 2. Traité des sensations. CONDILLAC. Paris. Paris. 3. Les Philosophes Français du dix-neuvième Siècle. Par HYPPOLYTE-ADOLPHE TAINE. Paris. 4. De l'Intelligence. TAINE. Paris. 5. Histoire de la Littérature Anglaise. TAINE. Paris. 6. System of Logic. By JOHN STUART MILL. London. DIFFICULT as is the pathway from sense to thought, from the mental to the physical domain, it is one that has proved peculiarly attractive to mankind, and among the earliest remains of human thought are metaphysical systems of considerable intricacy. Yet such truth as these contain is of that speculative character which the deep-thinking mind readily deduces from the ultimates of nature. It was left to the modern world to apply the rules of inductive science to this important question, and to attempt to build a bridge of hard facts from the physical to the metaphysical. Though there still yawns an apparently impassable abyss between sensation and consciousness, much has been done to narrow this chasm, and to make firm its approaches. Science, VOL. XXV.-NO. L. 1 that myriad-armed polypus, is grasping so tenaciously with its feelers the whole universe of matter and mind, that it has become unsafe to lay the finger on any point and say, this at least is beyond its reach. Daily the human body falls more and more within its grasp. The last outwork of speculation, the ancient dogma of vital force, is fast yielding to the assaults of chemistry; and Huxley, with his "Protoplasm," is likely to prove too strong for Beale, with his "Germinal Matter." It is, in fact, widely held that the animal body is but the product and the field of a refined chemistry; while, as for the phenomena of its organization, a host of comparative anatomists, developmentists, Darwinists, and others, are doing much to show that these are in strict subserviency to natural law, and that physically the animal nowhere transcends the known principles of nature. So, an equal host of mental physiologists and anatomists are tracing the correlations of mental phenomena, and feeling their way back from the most diverse results to certain broad and simple principles which lie at the basis of all the manifestations of the mind. Diligent research, too, is being made into the various relations between mind and matter, by a minute study of that refined instrument of combination, the nervous system. As a result of this broad extension of the field of science, its votaries are boldly hypothesising on subjects which, until of late, were considered as beyond the province of the reasoning faculties. In considering the nature of mental action, it becomes evident that we think largely through the medium of signs, names being a species of signs which replace past experiences. The human mind strongly tends to apply names to its sensations, and these names have the property of recalling the mental images which they signify. But, as man's experiences increase, it becomes difficult to remember everything by a special proper name, and a natural process of classification commences, resulting in the employment of common names. These are images of impossible experiences, since they suggest the common features in a group of dissimilar forms. All sensations are productive of mental images, which are recalled to consciousness by the act of memory. But the image aroused by a common name is indefinite. Thus the word tree produces a mental tendency to conceive of certain trees, the characters peculiar to each being repressed by their lack in the others, so that the image resulting becomes vague in form, though precise in idea. Thus a general name represents a quality common to a group of forms, which quality has a precise signification to our minds, though unconformable to any special sensation. Names, once given, rapidly fill out as our information increases, and from a single quality come to denote a group of abstract qualities. Thus the name collects within itself several less general names, of which it becomes the substitute. Such substitutes are what we term ideas. These, then, are mental images of abstractions which have no sensational existence, but result from an original analysis of groups of sensations, and a subsequent synthesis of the qualities thus obtained.* There are certain general characters which fail to produce distinct impressions. Of these is the notion of number. We can get no mental image of a composite number, as, for instance, 36. But unity may associate itself in our mind with a physical object. Now 36 is simply a substitute in our mind for 35 and unity, and we may trace back our idea to a series of 36 separate substitutions by which the human mind has advanced from the level of observation to a composite abstraction. The science of mathematics is entirely made up from an extension of this principle of substitution, which is mathematically extensible into infinity. We cannot conceive of the totality of an infinite series, but simply of its necessity, the mind finding itself in a path which has evidently no end. The sensations which we have experienced have the property of spontaneously reviving in the mind. These reproductions are less energetic and precise than the original, and may be named images. They vary greatly in force and pre * Les ideés sont, comme les sensations, des manières d'etre de l'ame.Condillac's Logique, p. 83. cision in different persons and under different circumstances. The image may become so strong as to be mistaken for the corresponding sensation, at least momentarily. The idea of externality in the image is usually suppressed by a rectification, generally the presence of existing sensations, which pronounces it internal. If the rectification be lacking, only the illusion remains, thus producing a case of hallucination. Various reductives act to overcome this result, such as a suppression of the exciting sensation, reminiscences, and general judgments. If all reductives are annulled, mental alienation results. As instances of the precision which images may sometimes attain, chess-players, who play without seeing the board, profess to have before them, projected upon space, an image of the board with all its pieces properly placed. So, certain painters can place an image of their sitter in the accustomed chair, and paint from it as distinctly as from the reality. In like manner a precise image of the whole musical performance will often affect a musician on seeing the notation of a tune. There is great difference of ability in persons in making their images seem real. Goethe could produce in himself a complete illusion at will, for instance, appearing to see a fantastic flower which had no real existence out of his mind. In the reverie preceding sleep, this frequently occurs. Sensation is then dormant and mental images assume the distinct prominence of sensations, becoming complete hallucinations.* Such distinct images will overcome real sensations. A German physican, named Gruithuisen, who closely observed his power of producing images, saw them projected with such apparent reality as to hide the furniture from sight.† A French soldier, who became nervously excited from witnessing an execution, gradually became imbued with the idea that he himself was to be executed. From being a mere fancy this grew into a complete hallucination. He saw what seemed real preparations, heard what seemed real voices, and thus gradually passed from a healthy condition into mental aliena *Maury, Le Sommeil, p. 458. Baillarger, Des Hallucinations, p. 333. |