VIII. THE SPECIAL SENSES. To Aristotle, as to the ordinary understanding, there are five distinct senses which require to be considered by the psychologist'. The first chapter of the third book of the Psychology even tries to make it appear that we do not possess more: but the reasoning, however we may try to connect it, is distinctly inconclusive. These senses stand to one another in a relation not unlike that in which the different forms or faculties of soul are connected. Just as the vegetative capacities are regarded as the basis on which all the other faculties repose, so in like manner touch is the sense which all the other senses presuppose. Touch is, in fact, the most common of all the perceptive faculties: it is that which all animals necessarily possess: and its final cause is of a humbler nature than that of the other senses. Sight and hearing are directed to our moral advancement, our intellectual development-they are Toû ev Čŷv éveka: whereas touch and taste are intended for our bare subsistence, contribute to nothing but our animal existence, are in short simply Toû Çîv éveкa3. And hence presumably it is that Aristotle begins his analysis of the different senses with sight, and ends with touch, treating, that is, the senses not in the order of history but in that of nature. But it seems here more in accordance with the course we have previously followed to proceed from the lower to the higher, and thus begin with touch and gradually end with hearing and sight. Touch' is a sense of which Aristotle finds the analysis peculiarly perplexing. Each of the three points, which we noticed (p. lxii.) as requiring to be studied, presents some difficulty. As to its object-how comes it that the sense perceives qualities so opposite as hot and cold, dry and moist, hard and soft? Qualities so different as these cannot be brought under any one common 1 Hist. An. IV. 8, 532b29. 2 III. 13, 4352. 3 De Sensu, 1, 4374. De An. III. 3, 429a3. De An. II. 11, 422—424a. category; and yet none the less, each sense, it is to be presumed, perceives one class of objects. The difficulty here stated Aristotle can hardly be said to solve. He reminds us that the other senses have also sometimes a variety of opposites between which they have to judge: and he finally determines the object of the sense of touch as the distinctive qualities of body as body', these qualities being further explained as those which characterize the different elements, viz. hot and cold, dry and moist. Yet these qualities, Aristotle elsewhere tells us, cannot be reduced to fewer and thus his answer really leaves the matter where it was. On the difficulties connected with the organ and the medium Aristotle is more satisfactory. Immediately, of course, the flesh might be supposed to be the organ of sense-perception. But this result is scarcely in accordance with what happens in the other senses. There, when the object is placed directly on the organ of sense, no perception whatever is possible: and it might be expected that were flesh the organ of touch it would be equally unable to perceive through immediate contact. The fact in short would seem to be that the real organ of touch is something inward, and that the flesh is simply the medium by which the tangible qualities of body are transmitted. Nor does the fact that we appear to perceive these qualities by immediate contact invalidate such a conclusion. Were a membrane spread over the flesh, we should equally appear to perceive through contact on the part of the object with this membrane, while at the same time no one would maintain this membrane to be the organ of perception. Flesh then is simply the medium of touch: although it must be added that the medium here does not play the same part as it does in some among the other senses. It is, that is to say, not so much the vehicle as the concomi 1 423027, ἁπταὶ μὲν οὖν εἰσὶν αἱ διαφοραὶ τοῦ σώματος ἢ σῶμα. * De Generatione, 11. 2, 33014, δῆλον τοίνυν ὅτι πᾶσαι αἱ ἄλλαι διαφοραὶ ἀνάγονται εἰς τὰς πρώτας τέτταρας· αὗται δ ̓ οὐκέτι εἰς ἐλάττους· οὔτε γὰρ τὸ θερμὸν ὅπερ ὑγρὸν ἢ ὅπερ ξηρόν. 3 Part. An. II. 19, 6:635, οὐκ ἔστι τὸ πρῶτον αἰσθητήριον ἡ σὰρξ ἀλλ' ἐντός. * De An. 11. 11, 413016, ὥστε τὸ μεταξὺ τοῦ ἁπτικοῦ ἡ σάρξ. W. AR. tant of sensation-the mode in which our sensations of touch are gained may be compared with the manner in which a man may be wounded through his shield'. Taste' is viewed by Aristotle as a species of touch, differing only in that, while touch is disseminated over the whole body, taste is restricted to a single part of it-the tongue. Its object is flavour (xvuós): and this is undoubtedly some modification of the moist or watery. But how it is that flavours originate from water is a question on which Aristotle finds divergent views are entertained. It cannot be, as Empedocles maintained, that water contains implicitly the various flavours in it; nor can it be, as Democritus perhaps held, that water is an atomic compound which contains the germs of all flavours, so that some may originate from one part, others from another part: rather it must be some affection of the water at the hands of some productive agent which produces flavour3. Flavour is accordingly defined by Aristotle as such a kind of affection produced in what is moist by what is dry as transforms the mere potential capacity of taste into actual exercise*. Of flavour various kinds are enumerated and compared with the different kinds of colour. The simple flavours are, like the simple colours, two in number-sweet and bitter-while the others may be regarded as modifications of these two primary kinds. The organ of taste can be as little localized as can that of touch. Popularly, of course, the tongue is regarded as the part concerned with the perception of flavours: and Aristotle often speaks as if he held himself the tongue to be the instrument of taste. But this of course is only a concession to the customary language 1 423 14, τῶν ἁπτῶν οὐχ ὑπὸ τοῦ μεταξὺ ἀλλ ̓ ἅμα τῷ μεταξὺ αἰσθανόμεθα ὥσπερ ὁ δι' ἀσπίδος πληγείς. De An. II. 10. De Sensu, c. 4. * De Sensu, 4, 441320, λείπεται δὴ τῷ πάσχειν τι τὸ ὕδωρ μεταβάλλειν. 4 44119, καὶ ἔστι τοῦτο χυμὸς τὸ γιγνόμενον ὑπὸ τοῦ εἰρημένου ξηροῦ πάθος ἐν τῷ ὑγρῷ τῆς γεύσεως τῆς κατὰ δύναμιν ἀλλοιωτικὸν εἰς ἐνέργειαν. 5 423 10 5 442012, ὥσπερ δὲ τὰ χρώματα ἐκ λευκοῦ καὶ μέλανος μίξεως ἐστιν, οὕτως οἱ χυμοὶ ἐκ γλυκέος καὶ πικροῦ. 6 Hist. An. IV. 8, 53326. of mankind: in reality, Aristotle views the tongue as little more than medium in the transmission of the flavour of ex ternal objects. Neither however in taste nor touch is the medium some external body as it is in the case of sight or hearing rather, whereas sight, smell and hearing act at a distance from their object, touch and taste operate in close proximity by means of almost actual contact'. At first sight, water might be thought to be the medium in the case of taste: but still, though "if we were in the water we should perceive anything sweet cast into it, our perception would be the result, not of the intervening medium, but simply of the mingling of the sweet thing with the water?" Still it is at least evident that the tongue must be potentially moist in order to perceive the different flavours. At the same time it must preserve that condition of indifference and equidistance from the two extremes of moist and dry without which no perceptive faculty is capable of action. And thus the sick, Aristotle adds by way of explanation, have but an imperfect sense of flavours because their tongue is imbued with such an amount of moisture as makes it impossible for them to acquire the taste of other flavours. Smell' Aristotle finds a sense which is somewhat difficult to analyse just as up to the present day it has been treated with much less success than any of the other senses. The reason for this backward condition of psychology in regard to odours is, Aristotle thinks, due to its defective development in man. While man possesses a much finer sense of touch than any other animal, "we do not," he adds, "possess the sense of smell in anything like the same degree of delicacy as that in which it is possessed by other animals." In the case of man, scent would seem to be merely a sort of concomitant upon feelings of pain and pleasure and to be perceived only indirectly, 1 II. 11, 42366. 13 422 11, οὐκ ἦν δ ̓ ἂν ἡ αἴσθησις ἡμῖν διὰ τοῦ μεταξὺ ἀλλὰ τῷ μιχθῆναι τῷ ὑγρῷ. 3 42263. De An. 11. 9. De Sens. c. 5. much in the same way as some animals possess the sense of sight only as a vague consciousness of a distinction between the dangerous and dangerless. In this comparative obscurity of the sense of smell, Aristotle has recourse to taste as a percipient faculty of not uncognate character and much more fully understood. Taste and smell indeed present to Aristotle's mind a constant parallel to one another. The object of both is a combination of the moist and dry: but while flavour is contained in water only, the object of smell or odour exists at once in air and water. Odour in fact belongs to what is dry, just as flavour belongs to what is moist': and the object of smell is thus said to be a dryness which holds taste or sap within it (Ĕyxvμos §npóïns3). The popular account of odour as a smoke-like exhalation (καπνώδης ἀναθυμίασις) Aristotle views as on the whole untenable. Such an exhalation cannot possibly exist in water, and it is in water to a great extent that smells come to be perceived. The organ and the medium of smell are closely in accordance with this quality of odours. Air and water may both serve as media. An object in short is perceived as odorous in so far as it is adapted to rinse out' as it were the taste-like dryness which constitutes as we have seen the general character of smell. This would seem to be a result which both air and water are able to perform: and the question therefore arises, what is the common characteristic present at once in air and water which makes them thus to disseminate and transmit the fragrant qualities of body? To this question Aristotle has no definite answer to give us. In one passage he speaks of this common quality as something 'nameless,' nor do we elsewhere find any more satisfactory answer. of smell is The organ 1 42246, ἔστι δ' ἡ ὀσμὴ τοῦ ξηροῦ, ὥσπερ ὁ χυμὸς τοῦ ὑγροῦ. 2 De Sensu, 5, 44397. 3 Ibid, 5, 443a21. No doubt in c. 2, 438°24 we have ǹ ♪ doμn kanvwôŋs tis ėstiv ȧvaðvulacis asserted as the ground for referring the organ of smell to fire, but the passage in question seems a mere hypothesis to shew how on the popular assumption that each sense corresponds to some element or other, smell would have to be referred to fire. See Bäumker, p. 47, who in 16 reads pavepòv ws ei deî. De An. 4218. 3 De Sensu, +4219, πλυντικὸν ἡ ῥυπτικὸν ἐγχίμου ξηρότητος. • De An. II. 7, 9, 419*32. |