Book 10
1.63
Next, keeping in view our perceptions and feelings (for so shall we have the surest grounds for belief), we must recognize generally that the soul is a corporeal thing, composed of fine particles, dispersed all over the frame,Cf. Lucr. iii. 161-176, 177-230. most nearly resembling wind with an admixture of heat,Cf. Lucr. iii. 231-257, 425-430; Epic. Fr. (Us.) 315, 314. These authorities assume four component elements, while in this epistle one of these (ἀερῶδές τι) is omitted. in some respects like wind, in others like heat. But, again, there is the third part which exceeds the other two in the fineness of its particles and thereby keeps in closer touch with the rest of the frame.The so-called nameless substance (nominis expers Lucr. iii. 242, ἀκατον όμαστον in Epicurus). And this is shown by the mental faculties and feelings, by the ease with which the mind moves, and by thoughts, and by all those things the loss of which causes death. Further, we must keep in mind that soul has the greatest share in causing sensation.
1.64
Still, it would not have had sensation, had it not been somehow confined within the rest of the frame. But the rest of the frame, though it provides this indispensable conditionThe body, by keeping soul-atoms together without much dispersion, allows them to vibrate with the motions that generate sentience and sensation. for the soul, itself also has a share, derived from the soul, of the said quality; and yet does not possess all the qualities of soul. Hence on the departure of the soul it loses sentience. For it had not this power in itself; but something else, congenital with the body, supplied it to body: which other thing, through the potentiality actualized in it by means of motion, at once acquired for itself a quality of sentience, and, in virtue of the neighbourhood and interconnexion between them, imparted it (as I said) to the body also.
