ABSTRACT
Now we have said above that from the brain, which is the sense of senses (i.e., the source of all sensation), the first exit of the nerves cometh to the eyes and causeth in them the sense of sight, and that the second exit is divided between those muscles that move the eyes. The third exit of the nerves cometh to the tongue, and causeth therein the sense Page 95 of taste and feeling; now the nerves that make it move are those which come to it from the seventh exit, which is by the side of the beginning of the spinal cord. The tongue is an instrument of two-fold use, viz., taste and speech, and its auxiliaries in this are the lips, the teeth, and the nose. Now as it is the construction that is in the eyes which sheweth us the causes of the things that happen, so also is it the. tongue which sheweth us, if we understand well, which is the primary instrument of feeling in it, and which are the members which perform its service. For we shew in other places that because the tongue serveth for two powers, that is to say, for one which belongeth to sensation and for the other which 'belongeth to the will, it possesseth two operations. Now we see sometimes that the motion of the tongue is injured, I and sometimes Fol. 46b. its sense of taste; and at other times besides this we see that its sense of touch is injured. But the nerves which belong to the sense of touch (or, feeling) are not one group and those which belong to the sense of taste another, as are those which appertain to its motions. And those which come to it from the third exit are not only those which make known the things
that are to be felt, but also those that are to be tasted. For the sense of taste is injured far oftener than the sense of touch (or, feeling), although they both belong to the [same] nerves, as if it had need of the sense of exact knowledge. For that sense appeareth to be much more dull of perception than the others, as, for example, that of sight, which is well known to be the most delicate of them all. Now after sight the sense most delicate is that of hearing, and similarly also is it in the case of dullness of perception (or, touch), for after that sense cometh next the sense of taste. In the middle of the four of these cometh the sense of drawing the breath.
