[96] Ibid. p. 443, b. 17; p. 444, a. 6. 15, 28: ἴδιον δὲ τῆς τοῦ ἀνθρώπου φύσεώς ἐστι τὸ τῆς ὀσμῆς τῆς τοιαύτης γένος διὰ τὸ πλεῖστον ἐγκέφαλον καὶ ὑγρότατον ἔχειν τῶν ζῴων ὡς κατὰ μέγεθος.
Plato also reckons the pleasures of smell among the pure and admissible pleasures (Philebus, p. 51, E.; Timæus, p. 65, A., p. 67, A.).
Taste is a variety of touch, and belongs to the lower or nutritive soul, as a guide to the animal in seeking or avoiding different sorts of food. The object of taste is essentially liquid, often strained and extracted from dry food by warmth and moisture. The primary manifestation of this sensory phenomenon is the contrast of drinkable and undrinkable.[97] The organ of taste, the tongue, is a mean between dryness and moisture; when either of these is in excess, the organ is disordered. Among the varieties of taste, there are two fundamental contraries (as in colour, sound, and the objects of the other senses except touch) from which the other contrasts are derived. These fundamentals in taste are sweet and bitter; corresponding to white and black, acute and grave, in colours and sounds. The sense of taste is potentially sweet or bitter; the gustable object is what makes it sweet or bitter in actuality.[98]
[97] Aristot. De Animâ, II. x. p. 422, a. 30-33. De Sensu et Sensili, i. p. 436, b. 15; iv. p. 441, b. 17: διὰ τοῦ ξηροῦ καὶ γεώδους διηθοῦσα (ἡ φύσις) καὶ κινοῦσα τῷ θερμῷ ποιόν τι τὸ ὑγρὸν παρασκευάζει. καὶ ἔστι τοῦτο χυμὸς τὸ γιγνόμενον ὑπὸ τοῦ εἰρημένου ξηροῦ πάθος ἐν τῷ ὑγρῷ. — Ib. b. 24: οὐ παντὸς ξηροῦ ἀλλὰ τοῦ τροφίμου.
[98] Aristot. De Animâ, II. x. p. 422, b. 5-16; II. xi. p. 422, b. 23: πᾶσά τε γὰρ αἴσθησις μιᾶς ἐναντιώσεως εἶναι δοκεῖ, &c.
The sense of touch, in which man surpasses all other animals, differs from the other senses by not having any two fundamental contraries giving origin to the rest, but by having various contraries alike fundamental. It is thus hardly one sense, but an aggregate of several senses. It appreciates the elementary differences of body quâ body — hot, cold, dry, moist, hard, soft, &c. It is a mean between each of these two extremes; being potentially either one of them, and capable of being made to assimilate itself actually to either.[99] In this sense, the tangible object operates when in contact with the skin; and, as has been already said, much of the superiority of man depends upon his superior fineness and delicacy of skin.[100] Still Aristotle remarks that the true organ of touch is not the skin or flesh, but something interior to the flesh. This last serves only as a peculiar medium. The fact that the sensation arises when the object touches our skin, does not prove that the skin is the true organ; for, if there existed a thin exterior membrane surrounding our bodies, we should still feel the same sensation. Moreover, the body is not in real contact with our skin, though it appears to be so; there is a thin film of air between the two, though we do not perceive it; just as, when we touch an object under water, there is a film of water interposed between, as is seen by the wetness of the finger.[101] The skin is, therefore, not the true organ of touch, but a medium between the object and the organ; and this sense does in reality agree with the other senses in having a certain medium interposed between object and organ. But there is this difference: in touch the medium is close to and a part of ourselves; in sight and hearing it is exterior to ourselves, and may extend to some distance. In sight and hearing the object does not affect us directly; it affects the external medium, which again affects us. But in touch the object affects, at the same time and by the same influence, both the medium and the interior organ; like a spear that, with the same thrust, pierces the warrior’s shield and wounds the warrior himself.[102] Apparently, therefore, the true organ of touch is something interior, and skin and flesh is an interposed medium.[103] But what this interior organ is, Aristotle does not more particularly declare. He merely states it to be in close and intimate communication with the great central focus and principle of all sensation — the heart;[104] more closely connected with the heart (he appears to think) than any of the other organs of sense, though all of them are so connected more or less closely.
[99] Ibid. xi. p. 422, b. 17 seq.
[100] Aristot. Histor. Animal. I. xv. p. 494, b. 17. Man is λεπτοδερμότατος τῶν ζῷων (Aristot. De Partib. Animal. ii. p. 657, b. 2), and has the tongue also looser and softer than any of them, most fit for variety of touch (p. 660, a. 20) as well as for articulate speech.
[101] Aristot. De Animâ, II. xi. p. 423, a. 25-32.
[102] Ibid. p. 423, b. 12-17: διαφέρει τὸ ἁπτὸν τῶν ὁρατῶν καὶ τῶν ψοφητικῶν ὅτι ἐκείνων μὲν αἰσθανόμεθα τῷ τὸ μεταξὺ ποιεῖν τι ἡμᾶς, τῶν δὲ ἁπτῶν οὐχ ὑπὸ τοῦ μεταξὺ ἀλλ’ ἅμα τῷ μεταξύ, ὥσπερ ὁ δι’ ἀσπίδος πληγείς· οὐ γὰρ ἡ ἀσπὶς πληγεῖσα ἐπάταξεν, ἀλλ’ ἅμ’ ἄμφω συνέβη πληγῆναι.