解密人类对长生不老的痴迷

If anything, readers might want more of Mr Cave's crisp conversational prose. There could be more on living longer; Mr Cave barely has time to give even the briefest overview of the emerging science of life extension, which has allowed researchers to lengthen the lifespans of mice by a third or more in the lab.

卡夫先生的文体清新，像对话式的散文。但读者可能会觉得他应当涉及更多的话题。比如怎样能够更长寿。卡夫先生甚至没有对新兴的抗老医学做简单的介绍，抗老医学的研究者们已经可以在实验室里把老鼠的寿命延长三分之一甚至更多。

There are a few quibbles. Mr Cave's repeated claim that the quest for immortality drives every human activity feels overdone. Others might dispute his definition of immortality itself. Mr Cave's chief argument against the desirability of living for ever (even assuming it is possible) is the familiar one of boredom. As the uncountable billions of years tick away, the argument runs, even the most vivacious will come to realise that they have done everything there is to do, hundreds of times. With yet more billions of years looming ahead they will be struck down with a debilitating ennui.

对卡夫先生的书，我有几点吹毛求疵的意见。例如，他反复强调，对永生的追求是人类所有行为的推动力，这一点似乎言过其实了。另外，他对永生的定义本身可能也会引起争议。再者，卡夫先生不赞成追求永生（假定能够实现）的主要论点，仍然是常见的“永生会造成厌倦”的见解。这种见解认为：在活过了算不清的数百万年之后，即便是最生动活泼的人也终会意识到，世上所有能做的事都被做了几百次了；如果再活数百万年的话，只会越来越无聊了。

That argument only applies if these notional immortals are also invincible, and therefore impervious to accident. But that is an odd definition, and not one that crops up very often, especially in scientific research into ageing. The holy grail there is simply to arrest the ageing process. Indeed, Mr Cave quotes an actuary who has estimated that the average "medical immortal" would persist for around 6,000 years before dying in a plane accident or a car crash or the like. And besides, boredom seems to be a non-problem: after all, if an immortal does ever get truly bored of his vastly extended life, there would be nothing to prevent him from ending it.

然而，这种见解能够成立的前提是：这些假想的长生不老者同时也是刀枪不入者，因而不会被任何事故所损伤。但这种前提是难以成立的，特别是与研究老化的科学成果相悖。这种科学的目的仅仅是延缓老化。确实，卡夫先生引用了一位精算师的估算结果：即使在医学意义上能够长生不老的人，平均寿命大约也只有六千年，因为他们也终会由于飞机失事或汽车事故而死去。此外，厌倦看起来不是什么问题：假如一个长生不老的人实在由于活得太长而厌倦了，他随时可以结束自己的生命嘛。