Touch is regarded by many writers as the most objective

together-5928481_1280 Image by AndPan614 from PixabayTouch is regarded by many writers as the most objective and the most trustworthy of all our faculties. It has been described as the source of our knowledge of the existence of an external world, and of the real magnitudes, figures, and distances of objects; as the instructor of the other senses, and tire corrector of their aberrations. It appears certain, however, that the sense of touch in itself is equally limited in its sphere with the rest of the senses, and that it can convey no other proper perception than that of the existence of its own organism as extended.

The sensations of touch considered by themselves, present no characteristics which can distinguish them from those of the other senses, as regards an immediate cognisance of the external world. Like smell, or sound, or light, they are affections of the nervous system, which may be produced by internal as well as external causes, and which directly indicate no other existence than that of the organised sentient being.

The fact is, that in the examination of this faculty, philosophers have often made a twofold confusion between things in themselves distinct. In the first place, the sense of touch proper, in which the sentient subject is as passive as in any other state of sensation, is confounded with the faculty of locomotion, which originates in a voluntary act of the same subject. In the second place, the sense of touch having no special organ, but being common to all parts of the surface of the body, it has sometimes happened that perceptions have been assumed to be invariable and absolute, which, in truth, are relative to one part only of the organism, and assume a different character in relation to other parts.

Now, in the first place, it is obvious that mere touch, without the power of locomotion, can inform us of no other magnitude than that which corresponds to the touching organ. In point of fact, it informs us only of the extension of the organ itself; but under no possible hypothesis could it inform us of more than the magnitude of that part of a body with which we are actually in contact.

In the second place, it has been proved by experiment that the same object will appear of a different magnitude when in contact with different parts of the human body, and consequently that the sense of touch, regarded by itself, is not only variable, but even self-contradictory in its testimony. Hence it follows that the sense of touch alone has no pre-eminence over the other senses as a criterion of truth in relation to a material world beyond our own organism: in fact, like the other senses, it is silent as to the existence of such a world.

***Excerpt from Henry Longueville Mansel, B.d.. Metaphysics or the philosophy of consciousness