Even if the last argument for the immortality of the soul in the Phaedo succeeds to show that deathlessness is among the soul’s essential properties, it fails to establish that the soul is indestructible. However, a less prominent, extensive, sophisticated and, in some details, surprising argument in book 10 of the Republic (Pol. X 608d-611a) is supposed to show precisely this. It relies on an elaborate story about change-makers, since it argues for the indestructibility of the soul against the background of a general theory of changes for the worse in things and how they are effected. Its central notion is that of a thing’s specific proper badness (kakía, ponería) as the cause of its perishing. Food poisoning is analysed as one proper badness (being rotten) in one thing (food) inducing another badness (disease) in a different thing (the body). The soul is held to be indestructible because, exceptionally, its proper badnesses, although making it bad, are not destructive; and because bodily badnesses do not induce badnesses of the soul according to the natural order of bad-makers.
This lecture will be given on Thu, 1 July 2021, 09:10 (UK time) as part of the workshop Change and Changemakers in Ancient Philosophy. The workshop is a collaborative initiative of the Change and Changemakers Network (Siegen) together with the Mereology of Potentiality Project (Oxford).