but they never actually kill you.

但衰老始终没让你死去
This is the sort of thought experiment

类似这样的思想试验
that Jonathan Swift undertakes in the passage

在我推荐你们阅读的乔纳森·斯威夫特
from Gulliver's Travels that I've had you look at.

写的《格列佛游记》里也有描述
He imagines Gulliver coming to a country

他想象格列佛来到一个国家
where a subset of the people live forever, immortals.

那里有些人永远不死永生
And at first, Gulliver says, "Oh, isn't this wonderful?"

起初格列佛说哦这太好了
But he forgot to think about the fact

但他忘记了
that if the kinds of changes that we undergo continue to accumulate,

由于身体上的变化不断积累
then you're getting older.

人们不断变老
Not just older, but weaker,

不仅变老而且越来越虚弱
in more and more discomfort,

身体越来越不舒服