所有的飞机师，其表现在某种程度上按照年龄增长而衰退。我们每个人都有类似的退化反应。

For all of the pilots, performance declined somewhat as the years passed. A similar decline with age is common in all of us.

youdao

智力能够看到它自己的活动，这些活动在导致退化，但是它却完全没有能力终止自身的衰退，因为本质上它只是一个局部。

The intellect can perceive its own activities which bring about degeneration but it is utterly incapable of putting an end to its own decline because essentially it is only a part.

youdao

身体开始退化，记忆开始衰退，每件事都证明我们老了。

Body start to degenerate, memory start to forget, everything shows we are old.

youdao