which constitutes sensation is dissolved, as harmony and tone become discordant, when the chords are struck too forcibly.
But why do not plants feel, seeing that they also possess a living part, and are impressionable by tangible qualities? And that they are so impressionable is shewn in their being both cooled and heated; but the cause is that they have not that mediate faculty, nor any such principle as admits of their receiving only the forms of things; that along with forms they are affected by the matter also.
It may be questioned whether impressions can be made by odour upon what may be without smell, or by colour upon what may be without vision, and so for other qualities and senses. But if that which is smelt be odour, then odour, if it produce anything, must produce smell, and thus nothing without smell can be affected by odour, and the same holds good for the other senses; neither can beings which are sentient be affected, save in so far as they are sentient. All which is made evident in that neither light nor darkness, sound nor odour, can act upon bodies, although that which is present with them may, as air with thunder splits wood. But yet tangible and sapid qualities do act upon bodies; for, otherwise, by what could inanimate things be acted upon and changed? Shall it then be said that those other qualities also act upon bodies? But all bodies
