PERSONAL IDENTITY. 93 



becomes the medusa again, not, we say, by these same 

 processes of nutrition and waste, but by a series of 

 generations, each one involving an actual birth and 

 an actual death. Why this difference ? Surely only 

 because the changes in the offspring of the medusa are 

 marked by the leaving a little more husk behind them, 

 and that husk less shrivelled, than is left on the 

 occasion of each change between the caterpillar and 

 the butterfly. A little more residuum, which residuum, 

 it may be, can move about ; and though shrivelling from 

 hour to hour, may yet leave a little more offspring 

 before it is reduced to powder; or again, perhaps, be- 

 cause in the one case, though the actors are changed, 

 they are changed behind the scenes, and come on in 

 parts and dresses, more nearly resembling those of the 

 original actors, than in the other. 



When the caterpillar emerges from the egg, almost 

 all that was inside the egg has become caterpillar ; the 

 shell is nearly empty, and cannot move ; therefore we 

 do not count it, and call the caterpillar a continuation 

 of the egg's existence, and personally identical with 

 the egg. So with the chrysalis and the moth ; but 

 after the moth has laid her eggs she can still move her 

 wings about, and she looks nearly as large as she did 

 before she laid them ; besides, she may yet lay a few 

 more, therefore we do not consider the moth's life as 

 continued in the life of her eggs, but rather in their 

 husk, which we still call the moth, and which we say 

 dies in a day or two, and there is an end of it. 

 Moreover, if we hold the moth's life to be continued 

 in that of her eggs, we shall be forced to admit her 



