recognizable

You might think that death is part of our nature or that mortality is essential to our nature as human beings. If so, then immortal beings would be radically different than us, so different in fact that they would not be recognizable as beings like us. So if you were offered a Faustian bargain to trade your humanity for the promise and reality of immortality, it wouldn't be worthwhile. 

In this episode, I discuss Fischer's defense that immortality is worthwhile against a battery of objections: that the lives of immortals would be shapeless or without form; that certain human goods like friendship, relationships, personal achievements, and virtue are unavailable to immortals; that endings are crucial for a life story; that in a never-ending story one cannot re-evaluate the past; that an infinite life is inconceivable; and that recognizably human lives must have end stages. While Fischer's defense against these objections succeeds in my view, he goes too far and endorses the view that there are no relevant differences between mortal and immortal lives with respect to which goods they can realize, hesitating only on whether marriage would need amendation between immortals. Fischer further adopts a motte-and-bailey approach when responding to these objections, retreating to the desirability of medical immortality when the objections are too strong against true immortality.

Instead, I argue that we should drop Williams' recognizably condition altogether, which becomes more apparent once we see how it is a sufficient similarity condition in disguise. Being recognizably human in the future is equivalent with being sufficiently similar to how one is now in some relevant respect (such as being mortal, or having certain goods or stages, etc.). However, a similarity condition is unnecessary on our future resembling our past and yields a kind of objectionable conservativism against too much change. And so Williams' recognizability condition should simply be rejected.