APHASIA IN RELATION TO LANGUAGE AND THOUGHT.
The relation of language to thought as a theme of discussion has busied the pens of philosophical writers from very early times, and the later aspects of the controversy do not promise a speedy agreement of views. Whatever new light, therefore, recent discoveries in science may shed on this much-vexed question ought to be welcomed as helping to increase of knowledge concerning a matter which cannot escape the serious consideration of the teachers of philology. At present Messrs. Max Müller and Whitney most strongly incline to opposite views; and before coming to the subject of aphasia as affecting the question, it may be well to take a cursory view of the field of controversy.
The old or scholastic belief is that language was in the first instance divinely communicated, and this opinion its upholders strove to maintain by a variety of reasons. Authority and tradition were chief among these, though they did not by any means neglect philological and ethnological considerations. In France the Vicomte de Bonald undertook the support of this view on the same line as that now held by Max Müller—viz., that it is impossible to have a purely intellectual conception without a corresponding word or series of words to represent it; whence, according to him, it follows that the word must have accompanied the thought, and, man being unable to originate the one without the other, both must have been originally communicated. Max Müller says: “As a matter of fact, we never meet with articulate sounds, except as wedded to determinate ideas: nor do we ever, I believe, meet with determinate ideas, except as bodied forth in articulate sounds.” He strongly insists on the correctness of this view, and argues it at length. Professor Whitney takes direct issue with him, and maintains that there is the widest separation between language and thought. According to him, language can be said to be of divine origin only in so far as man was created with the capacity for its formation just as he was created capable of making
clothes for himself, and of wearing them. Such being the state of the question, we will proceed to consider that abnormal condition of the nervous system which has been denominated aphasia, and afterwards indicate our opinion as to which view the facts established by it go to sustain.
Aphasia, defined by Dr. Hammond as a diseased condition of the brain, was not understood till quite recently. It is an affection of that organ by which the idea of language or of its expression is impaired. It is not mere paralysis of the vocal chords, nor of the muscles of articulation, nor the result of hysteria—which conditions are denominated aphonia, or voicelessness—but depends on a lesion or injury wrought in that portion of the brain which presides over the memory of words and their co-ordination in speech. The loss of the memory of words is styled amnesic aphasia, the other ataxic aphasia—two Greek derivatives which explain very clearly the two separate conditions. A single typical case will exhibit the usual manner of the approach of this trouble, its development and termination. An English banker, a resident of Paris, recently went out in his carriage well as usual, and on his return, as he was stepping to the sidewalk, fell heavily forward, but did not lose consciousness. His whole right side was paralyzed, and, on attempting to speak, he could not articulate a word; he barely succeeded in uttering a few unintelligible sounds. During twelve days the paralysis continued, but after that gradually subsided, till in the course of a few months he was able to move about. Strange to say, however, the power of speech did not return, and for eight months he
could no more than articulate a few words incoherently. Nothing in the case of this gentleman openly indicated an impairment of the intellect; for he could neither read nor write in consequence of his paralyzed condition. There was undoubted loss of the memory of words, since his vocabulary was limited to two or three; and there was likewise ataxic aphasia, since his words were jumbled unmeaningly together. The recorded cases of this disease are very numerous, many of them differing in their individual features, but all exhibiting a greater or less degree of both forms mentioned. The case just cited will suffice to enable the reader to understand the interest felt by psychologists and physiologists alike to ascertain whether, by the discovery of a uniform and constantly-recurring lesion in a certain portion of the brain, the seat of language in that organ might be determined. Dr. Gall, with the view of completing his system of phrenology, referred speech-function to that part of the brain lying on the supra-orbital plate behind the eye. Spurzheim, Combe, and others of the phrenological school held the same view. But this was a mere conjecture on their part, and it was not till minute anatomy had already localized several other important functions that a fair promise was held out that the brain-organ of speech might be likewise located. Experiments without number were made by Bouillaud, Cruveilhier, Velpeau, Andral, Broca, and Dax in France; Hughlings, Jackson, Sanders, Moxon, Ogle, Bateman, and Bastian in England; Von Benedict and Braunwart in Germany; Flint, Wilbur, Seguin, Fisher, and Hammond in America—all tending to confirm the localization
of the function, though not agreeing as to the exact spot. The mode of procedure usually consisted in making a post-mortem examination of those who during life had suffered from aphasia; and though it was an extremely difficult matter to bring all the cases under a uniform standard, enough was discovered to assign the function in question to the left anterior lobe of the brain. We do not pretend to regard the question as settled; for no less authorities than Hammond in our own country, and Prof. Ferrier in England, seem to consider both hemispheres of the brain as equally concerned. Still, it is significant that out of 545 cases examined by different authorities, 514 favor the left anterior lobe of the brain, while but 31 are opposed to such a conclusion. Assuming, then, as amply demonstrated that some portion of the anterior convolutions of the brain is the seat of the faculty of speech, the question arises, Can that part of the brain which is concerned in the process of ideation continue to perform its functions—i.e., originate true ideas of which the mind is conscious—without the memory of the words which usually represent those ideas or the power to co-ordinate them? It is evident that, no matter how the question may be met, we possess in the discoveries to which aphasia has led a most important contribution to the controversy concerning the relation of language to thought; for if it can be shown that the mental faculties are unimpaired during the existence of the aphasic condition, the conclusion would go to favor Prof. Whitney’s view that thought is independent of speech; whereas if it can be shown that during the same condition the mental powers are very much debilitated or frequently suspended,
we find an unexpected support given to Max Müller’s opinion that without language there can be no thought. We would state in advance that the portion of the cerebral substance which is concerned in the production of thought—or, as neurologists have it, is the centre of ideation—entirely differs from that which is the reputed seat of the faculty of speech; so that the question may read: Does the centre of ideation continue to operate while the speech-centres are in a diseased condition? Aphasic individuals usually retain all the appearances of intelligence: their eyes are full of expression; their manner of dealing with surrounding objects is quite the same as if they were in possession of all their faculties; when asked to point out material objects, they unhesitatingly do so—in a word, to the extent that objects are their own language their intellect remains unimpaired. But they exhibit a remarkable deficiency in the power of co-ordination, since this is a pure relation not symbolized by anything material. Material objects possess in their outlines and sensible qualities enough to discriminate and individualize them; and hence, through perception, they reach the centres of ideation, and are as readily understood by the aphasic as though their names were fully known. This is made manifest in their writing when, as occurs only in a few cases, the aphasic retain the power of using the pen. Thus we read in Trousseau of the case of an aphasic named Henri Guénier, who could not write the word “yes,” though capable of uttering it in an automatic way without seeming in the least to understand its meaning. Yet he could write his own name, though nothing else, evidently for the reason that
the τὸ ἐγώ was the object of most frequent recurrence to his mind, and that which consequently he could most readily apprehend through its sensible characteristics, and could thereby connect with his own name; whereas “yes,” as the symbol of affirmation, found no counterpart in the sensible order. The same author relates the case of a man who, so far as he could make himself intelligible, boasted of retaining his intellective and memorative powers unimpaired, and yet, on being put to the test, he could not construct the shortest sentence coherently. When a spoon was held before him, and he was asked what it was, he gave no answer; when asked if it was a fork he made a sign of denial, but when asked if it were a spoon he at once replied in the affirmative. It must be remembered that in all these cases the power of utterance, so far as it is a muscular process, remained unimpaired, but there was true amnesic aphasia—i.e., the recollection of the words was lost.
There are some cases of partial aphasia which possess an interest quite peculiar, since its victims frequently regain the entire power of speech, and are able to relate the results of their experience. A celebrated professor in France spent a vacation-day reading Lamartine’s literary conversations, when towards evening he was attacked with partial aphasia. Fearing lest he was threatened with paralysis, he moved his arms and walked up and down the room, in doing which he experienced no difficulty; but when he resumed his reading, he found it scarcely possible to understand a sentence. The individual words were intelligible enough, but he could not follow out the sequence of the thoughts. Of course during the attack he could
not utter a word, though able partially to comprehend what was said to him, as he afterwards declared. Here indeed is a most instructive instance of impaired intellect, occurring as it did in a man whose brain was usually in a very active state, and whose mind was highly cultivated. Does it not strongly confirm the belief that, even while the organic instrument of thought was unimpaired, its functions were temporarily suspended?
Another case is that of a man of good literary attainments, who pretended that he could still understand what he read, but who could not discover the mistake when the book was presented to him reversed. There can be no doubt, then, that aphasia unerringly points to a most intimate dependence between language and thought, and that, as Max Müller says, without language there can be no thought.
But why is it that in regard to objects possessing sensible qualities aphasic individuals exhibit no impairment of intellectual power? We will answer, Because with regard to such objects these are their own language, and the functions of the perceptive and ideational centres are as active in their regard as though the faculty of speech were intact. A tree is known by its branches and leaves to the deaf mute as well as it is by its name to those possessing all their faculties. Whatever circumscribes and differentiates an object of thought is its language. For, after all, is not language conventional and arbitrary, the outer symbol of a subjective phenomenon? The symbol may be of any sort whatsoever, but the thought cannot be known without a symbol of some sort. Now, the qualities of sensible objects, in so far as they serve to circumscribe
the objects and to discriminate them from all others, become their language. This is rendered more evident when we reflect that Locke’s theory, according to which sensible objects are but an aggregate of sensible qualities, is generally rejected, and the opinion admitted that under these qualities there resides a true substance impervious to the senses and known to us only as inference from the former. Therefore the sensible qualities are the symbol of the substance identified with it; of course in so far these are but the substance modified in such or such a manner. This is why aphasics find no trouble in forming ideas of material things, though they may forget their names. But why is aphasia ataxic—that is, incapable of co-ordinating words? Because co-ordination expresses the relation between the objects co-ordinated, and relation is not represented, and cannot be represented, by anything in the sensible order. They belong to the purely intellectual order, and the only symbol that existed by which they were known being lost, there remains no longer any means of circumscribing and differentiating them. Paul and Peter may be well known to the aphasic—Paul as such, and Peter as such—because the sensible qualities of both render them recognizable; and not only that, but the different qualities pertaining to both enable him clearly to distinguish the one from the other. But if he is told that Peter is taller than Paul, he understands nothing. And why? Because the proposition implies the relation of comparison, in which there is nothing sensible. Indeed, he perceives Peter to be tall and Paul to be diminutive, but he does not perform the intellectual process called judgment, which is interpreted in
the proposition, Peter is taller than Paul. In like manner, when there is question of purely intellectual conceptions which can be symbolized by nothing sensible except names, the aphasic are incapable of reaching them. Virtue, power, and malice are meaningless sounds in their ears, and equally unintelligible is what these words represent. The reason is because the symbols by which these ideas were conveyed to the mind are lost, and there is nothing left by which virtue can be known or discriminated from power and malice. Whatever circumscribes and differentiates a thought is its language, and this can be done only by a symbol. Now, if we consult our own consciousness, we will find that it is impossible for us to conceive of what is purely intellectual—i.e., possessing no sensible traits—if we lose sight of the word which represents it. Affirmation and negation are of this sort, and it is entirely impossible to disconnect the idea of either from some word or series of words. The idea, indeed, is not the spoken word, but is painted by it as it were on the canvas of the mind, and hence was called by Aristotle the word of the mind. All this is attested in the case of aphasics. The language-mechanism of the brain is disarranged; there is forgetfulness of words, accompanied by inability to arrange them in proper order so as to be remembered; the ideational centre remains intact, but is inoperative with regard to such thoughts as have their sole symbol in words.
It is true that some aphasic individuals retain for a time certain impressions which belong to the purely intellectual order; but this can be accounted for only by supposing that the brain centres of ideation are endowed with certain registering
powers capable of retaining impressions for a short while after their active operation is suspended. But when the disease is of long continuance those impressions gradually fade, and the patient is reduced to the condition of an untaught deaf mute. He has lost the formulæ of thought, and therefore cannot think. Trousseau says: “A great thinker, as well as a great mathematician, cannot devote himself to transcendental speculations unless he uses formulæ and a thousand material accessories which aid his mind, relieve his memory, and impart greater strength to thought by giving it greater precision.” But where the sole “material accessory,” as Trousseau calls it, is absent, how can a person think? We use the word in a higher sense; for children incapable of speech, and animals, exercise a certain amount of thought in respect to surrounding objects; but thinking, in the sense of reasoning, abstracting, and comparing, outlies their capacity, just as it does that of aphasic individuals. “Without language,” says Schelling, “it is impossible to conceive philosophical, nay, even any human, consciousness; and hence the foundations of language could not have been laid consciously. Nevertheless, the more we analyze language, the more clearly we see that it surpasses in depth the most conscious workings of the mind.” And Hegel says: “It is in names that we think.” This exactly explains what occurs in the case of aphasics. The principles of science, the sequence of ideas, the links of an argument, are not understood by them; for they are, as children and animals, capable merely of receiving the impressions which material objects make on their sensory organs. It is true that a few aphasics have been known to be expert
chess-players; and though this is as hard to account for as the apparent feats of reasoning accomplished by animals of the lower order, still we would no more rank expertness at such a game among the higher attributes of reason than we would the sagacity of a dog or of an elephant.
This point is well touched upon by Trousseau, who says: “I believe that the same thing obtains in metaphysics as in geometry. In the latter case a man may vaguely conceive space and infinity without any precision or measure; but if he wishes to think of the properties of space, and more particularly of the special properties of the figures which bound space—as, say, conic sections—it is impossible that his mind does not immediately see the curves proper to a parabola, a hyperbola, and an ellipse. In metaphysics, on the other hand, I believe that a man cannot think of the special properties of beauty, justice, and truth, for instance, without immediately giving a material form, as it were, to his thoughts, by using concrete examples, and without associating words together—words which represent concrete ideas, and which then stand in the same relation to particular metaphysical ideas as figures do to determinate geometric ideas.”
The same may be said of universal ideas. These are, subjectively viewed, mere concepts of the mind; objectively they have a foundation in the object. Now, that object is present to the aphasic, and he recognizes it by its sensible properties; but when there is question of viewing one or two properties as possessed in common by a number of objects, he finds himself unequal to the task. In a word, he cannot generalize, and this is one of the highest acts of reason.
We would insist upon the distinction between words representing purely material objects and those which interpret to us supersensible thoughts; for not a few physiologists have fallen into error by not observing this distinction. Thus Prof. Ferrier, of the West Riding Lunatic Asylum, says: “In aphasia, consequent as it usually is on disease of the left hemisphere, the memory of words is not lost, nor is the person incapable of appreciating the meaning of words uttered in his hearing.” From this it is evident that the learned professor neglected to note the distinction alluded to; and because an aphasic did not fail to appreciate the meaning of certain words representing material things, therefore he concluded in a general way that he did not fail to appreciate the meaning of words. Indeed, we have nowhere noted the distinction, and it is curious that, in all the cases recorded of the clinical history of this disease, physicians have invariably propounded to their patients as test-words such words as fork, spoon, pen, boots, and all such as pertain to the material order of things. Prof. Whitney certainly did not take note of these facts
when he asserted the entire independence between language and thought. He regards man as capable of conceiving new thoughts apart from all representative symbols, and then finding for them a vocal expression. This, as we have seen, is in direct antagonism with the data of aphasia. The chief flaw in Prof. Whitney’s reasoning is that he starts from false premises when he limits language to mere spoken or articulate sounds. He seems to ignore the question when he says: “In all our investigations of language we find nothing which should lead us to surmise that an intellectual apprehension could ever, by an internal process, become transmuted into an articulated sound or complex of sounds.” The implied premise in this sentence is erroneous, since it is entirely possible that it be associated with some other symbol, borrowed from a material source, which is its language, its expression, and makes it something entirely distinct from the intellectual apprehension. Indeed, here lies the secret of metaphorical language, and of its extensive use among those tribes of men whose philosophical vocabulary is limited.