Arabian and Latin Schoolmen. Latin, schoolmen. were not at one in 2 touch. Alexander' favors, but not decidedly, the opposite opinion, which was espoused by Simplicius and Philoponus. The doctrine of Themistius was, however, under various modifications, adopted by Averroes and Avicenna among the Arabian, and by Apollinaris, Albertus Magnus, Ægidius, Jandunus, Marcellus, and many others among the These, however, and succeeding philosophers, regard to the number of the senses, which they would distinguish. Themistius and Avicenna allowed as many senses as there were different qualities of tactile feeling; but the number of these they did not specify. Avicenna, however, appears to have distinguished as one sense the feeling of pain from the lesion of a wound, and as another, the feeling of titillation. Others, as Ægidi Themistius and Avi cenna. Ægidius. us, gave two senses, one for the hot and cold, another for the dry and moist. Averroes' secerns a sense of titillation and a sense of hunger and thirst. Galen also, I should observe, allowed a sense of heat and cold. Among modern philosophers, Cardan" distinguishes four senses of touch or feeling; one of the four primary tactile qualities of Aristotle (that is, of cold and hot, and wet and dry); a second, of the light and heavy; a third, of pleasure and pain; and a fourth, of titillation. His antagonist, the elder Scaliger,12 distinguished as a sixth special sense the sexual appetite, in which he has been followed by Bacon13 Voltaire1 and others. From these historical notices you will see how marvellously incorrect is the statements that Locke was the first philosopher who originated this question, in al Bacon, Buffon, 1 Problemata, ii. 62 (probably spurious. ED. 2 In De Anima, lib. ii. c. xi. text 106, fol. 44ab (edit. Ald. 1527). — ED. 3 In De Anima, lib. ii. c. xi. texts 106, 107. - ED. 4 See Conimbricenses, In De Anima, lib. ii. c. xi. p. 326. — ED. 5 See preceding page, note 2, and Conimbricenses, as above, p. 327. - ED. 9 See Conimbricenses, In De Anima, lib. ii. c. xi. p. 327.-ED. 10 [Leidenfrost, De Mente Humana, c. ii. § 4, p. 16.] 11 De Subtilitate, lib. xiii. See Reid's Works, p. 867.-ED. 12 De Subtilitate, Ex. cclxxxvi. § 3. — Ed. 13 [Sylva Sylvarum, cent. vii. 693. Works, edit. Montagu, iv. 361.] 14 See Reid's Works, p. 124; and Poor, TheoVoltaire, ria Sensuum, pars i. 34, p. 38. Dict. Philosophique, art. Sensation, reduces this sense to that of Touch. Cf. Traité de Meta physique, ch. iv. Euvres Complètes, tom. vi. p. 651 (edit. 1817). - ED. 15 See Lectures on Intellectual Philosophy, by John Young, LL. D., p. 80. Hutcheson. Adam Smith. lowing hunger and thirst to be the sensations of a sense different from tactile feeling. Hutcheson, in his work on the Passions,1. says, "the division of our external senses into five common classes is ridiculously imperfect. Some sensations, such as hunger and thirst, weariness and sickness, can be reduced to none of them; or if they are reduced to feelings, they are perceptions as different from the other ideas of touch, such as cold, heat, hardness, softness, as the ideas of taste or smell. Others have hinted at an external sense different from all of these." What that is, Hutcheson does not mention; and some of our Scotch philosophers have puzzled themselves to conceive the meaning of his allusion. There is no doubt that he referred to the sixth sense of Scaliger. Adam Smith, in his posthumous Essays, observes that hunger and thirst are objects of feeling, not of touch; and that heat and cold are felt not as pressing on the organ, but as in the organ. Kant divides the whole bodily senses into two,-into a Vital Sense (Sensus Vagus), and an Organic Sense (Sensus Fixus). To the former class belong the sensations of heat and cold, shuddering, quaking, etc. The latter is divided into the five senses, of Touch Proper, Sight, Hearing, Taste, and Smell. This division has now become general in Germany, the Vital Sense receiving from various authors various synonyms, as cœnæsthesis, common feeling, vital feeling and sense of feeling, sensu latiori, etc.; and the sensations attributed to it are heat and cold, shuddering, feeling of health, hunger and thirst, visceral sensations, etc, adopted by Dr. Brown. He divides our sensations into those which are less definite, and into those which are more definite; and these, his two classes, correspond precisely to the sensus vagus and sensus fixus of the German philosophers.* Kant. Kant's division general in Germany. Brown. This division is, likewise, The propriety of throwing out of the sense of Touch those sensa Touch to be divided from sensible feeling. 1. From the analogy tions which afford us indications only of the subjective condition of the body, in other words, of dividing touch from sensible feeling, is apparent. In the first place, this is manifest on the analogy of the other special senses. These, as we have seen, are divided into two classes, according as perception proper or of the special senses. 1 Sect. i., third edition, p. 3, note.-ED. 2 Of the External Senses, p. 262 (ed.1800).-ED. 3 Anthropologie, § 15.-ED. [Previously to Kant, whose Anthropologie was first published in 1798, Leidenfrost, in his De Mente Humana, (1793), c. ii. § 2, p. 14, distinguished the Vital 4 Lectures xvii. xviii.—ED. sensation proper predominates; the sense of Sight and Hearing pertaining to the first, those of Smell and Taste to the second. Here each is decidedly either perceptive or sensitive. But in Touch, under the vulgar attribution of qualities, perception and sensation both find their maximum. At the finger-points, this sense would give us objective knowledge of the outer world, with the least possible alloy of subjective feeling; in hunger and thirst, etc., on the contrary it would afford us a subjective feeling of our own state, with the least possible addition of objective knowledge. On this ground, therefore, we ought to attribute to different senses perceptions and sensa tions so different in degree. 2. From the different quality of the perceptions and sensations themselves. But, in the second place, it is not merely in the opposite degree of these two counter elements that this distinction is to be founded, but likewise on the different quality of the groups of the perceptions and sensations themselves. There is nothing similar between these different groups, except the negative circumstance that there is no special organ to which positively to refer them; and, therefore, they are exclusively slumped together under that sense which is not obtrusively marked out and isolated by the mechanism of a peculiar instrument. Special Sense of Touch, its sphere and organic seat. Limiting, therefore, the special sense of Touch to that of objective information, it is sufficient to say that this sense has its seat at the extremity of the nerves which terminate in the skin; its principal organs are the finger-points, the toes, the lips, and the tongue. Of these, the first is the most perfect. At the tips of the fingers, a tender skin covers the nervous papillæ, and here the nail serves not only as a protecting shield to the organ, but, likewise, by affording an opposition to the body which makes an impression on the finger-ends, it renders more distinct our perception of the nature of its surface. Through the great mobility of the fingers, of the wrist, and of the shoulder-joint, we are able with one, and still more effectually, with both hands, to manipulate an object on all sides, and thereby to attain a knowledge of its figure. We likewise owe to the sense of Touch a perception of those conformations of a body, according to which we call it rough or smooth, hard or soft, sharp or blunt. The repose or motion of a body is also perceived through the touch. To obviate misunderstanding, I should, however, notice that the proper organ of Touch-the nervous papillærequires as the condition of its exercise, the movement of the voluntary muscles. This condition however, ought not to be viewed as a part of the organ itself. This being understood, the perception of the weight of a body will not fall under this sense, as the nerves lying under the epidermis or scurf skin have little or no share in this knowledge. We owe it almost exclusively to the consciousness we have of the exertion of the muscles, requisite to lift with the hand a heavy body from the ground, or when it is laid on the shoulders or head, to keep our own body Proper organ of Touch requires, as condition of its exercise, the movement of the voluntary muscles. Two counter questions regarding sphere of Sight. erect, and to carry the burthen from one place to another. I next proceed to consider two counter-questions, which are still agitated by philosophers. The first is, - Does Sight afford us an original knowledge of extension, or do we not owe this exclusively to Touch? The second is,-Does Touch afford us an original knowledge of extension, or do we not owe this exclusively to Sight? Both questions are still undetermined; and consequently, the vulgar belief is also unestablished, that we obtain a knowledge of extension originally both from sight and touch. 1. Does Vision afford us a primary knowledge of extension? or do we not owe this exclusively to Touch? I commence, then, with the first,- Does Vision afford us a primary knowledge of extension, or do we not owe this knowledge exclusively to Touch? But, before entering on its discussion, it is proper to state to you, by preamble, what kind of extension it is that those would vindicate to sight, who answer this question in the affirmative. The whole primary objects of sight, then, are colors, and extensions, and forms or figures of extension. And here you will observe, it is not all kind of extension and form that is attributed to sight. It is not figured extension in all the three dimensions, but only extension as involved in plane figures; that is, only length and breadth. It has generally been admitted by philosophers, after Aristotle, that color is the proper object of sight, and that extension and figure, common to sight and touch, are only accidentally its objects, because supposed in the perception of color. Color the proper object of Sight. This generally admitted. The first philosopher, with whom I am acquainted, who doubted or denied that vision is conversant with extension, was Berkeley; but the clear expression of his opinion is contained in his Defence of the Theory of Vision, an extremely rare tract, which has Berkeley the first to deny that extension object of Sight. Condillac. escaped the knowledge of all his editors and biographers, and is consequently not to be found in any of the editions of his collected works. It was almost certainly, therefore, wholly unknown to Condillac, who is the next philoso Laboulinière. pher who maintained the same opinion. This, however, he did not do either very explicitly or without change; for the new doctrine which he hazards in his earlier work, in his later he again tacitly replaces by the old. After its surrender by Condillac, the opinion was, however, supported, as I find, by Laboulinière. Mr. Stewart maintains that extension is not an object of sight. "I formerly," he says, "had occasion to mention several instances of very intimate associations formed between two ideas which have no necessary connection with each other. One of the most remarkable is, that which exists in every person's mind between the notions of color and extension. The former of these words expresses (at least in the sense in which we commonly employ it) a sensation in the mind, the latter denotes a quality of an external object; so that there is, in fact, no more connection between the two notions than between those of pain and of solidity; and yet in consequence of our always perceiving extension at the same time at which the sensation of color is excited in the mind, we find it impossible to think of that sensation without conceiving extension along with it." But before and after Stewart, a doctrine, virtually the same, is maintained by the Hartleian school; who assert, as a consequence of their universal principle of association, that the perception of color suggests the notion of extension.* Hartleian School. Brown. 8 Then comes Dr. Brown, who, in his Lectures, after having repeatedly asserted, that it is, and always has been, the universal opinion of philosophers, that the superficial extension of length and breadth becomes known to us by sight originally, proceeds, as he says, for the first time, to controvert this opinion; though it is wholly impossible that he could 1 The order of Condillac's opinions is the reverse of that stated in the text. In his earliest work, the Origine des Connoissances Humaines, part i. sect. vi., he combats Berkeley's theory of vision, and maintains that extension exterior to the eye is discernible by sight. Subsequently, in the Traité des Sensations, part i. ch. xi., part ii. ch. iv. v., he asserts that the eye is incapable of perceiving extension beyond itself, and that this idea is originally due solely to the sense of touch. This opinion he again repeats in l'Art de Penser, part i. ch. xi. But neither Condillac nor Berkeley goes so far as to say that color, regarded as an affection of the visual organism, is apprehended as absolutely unextended, as a mathematical point. Nor is this the question in dispute. But granting, as Condillac in his later view expressly asserts, that color, as a visual sensation, necessarily occupies space, do we, by means of that sensation, acquire also the proper idea of extension, as composed of parts exterior to each other? In other words, does the sensation of different colors, which is necessary to the distinction of parts at all, necessarily suggest different and contiguous localities? This question is explicitly answered in the negative by Condillac, and in the affirmative by Sir W. Hamilton. Cf. The Theory of Vision vindicated and explained. London, 1733. See especially, if 41, 42, 44, 45, 46.- ED. 2 See Reid's Works, p. 868.-ED. 3 Elements of the Philosophy of the Human Mind, vol. i. chap. v. part ii. § 1. Works, vol. ii. p. 306. [Cf. Ibid., note P.- ED.] 4 See Priestley, Hartley's Theory, prop. 20. James Mill, Analysis of Human Mind, vol. i. p. 73.- ED. 5 Lecture xxviii. — ED. |