壽命更長是否會更幸福呢？

One of the biggest questions in ageing research is whether there is a ceiling on how long human beings can live.

尋求人類壽命的極限是老齡化研究面臨的最大難題之一。

A recent study, published in Science, suggests there isnt. The study measured the survival probabilities of 3,896 people in Italy aged 105 and older. It found that, while we are much more likely to die at 75 than at 55, once we reach about 105, the odds of death remain about the same each year of life.

最近，一項刊登在《科學》雜誌上的研究指出，人類的壽命沒有上限。該研究調查了義大利3896個人的存活率，他們的年在105以上（含105歲）。以上研究發現，我們在75歲的死亡風險比55歲時更高，但一旦我們活到105歲，死亡幾率將不會上升，而是保持不變。

This effect is often referred to as a "mortality plateau". If it were impossible to live past a certain age, we would expect mortality rates to continue rising as people age, rather than plateau.

這個效應常常被稱為「死亡高原」。人們認為在變老的過程死亡率會繼續上升，而不是趨於平緩。

The fact that the odds of dying dont appear to increase past 105 suggests that we have not yet approached our maximum lifespan as a species. But is potentially living for over a century something we ought to look forward to? Here, philosophy can offer some important insights.

人們在105歲會經歷的「死亡高原」的事實說明，人類這一種族還沒有達到壽命極限。但是我們是否希望自己能活過100歲呢？

Its time to measure aging with 21st-century tools

是時間用21世紀的工具測量衰老程度了。

Of course, we still dont know for sure that there is no ceiling. Some researchers argue that there is a natural "expiration date" for human beings, at about?125 years. Chiyo Miyako is currently the oldest known person in the world, at 117 years old. Jeanne Calment, who died in 1997, had the longest recorded lifespan, at 122 years.

當然，我們確實不知道是否存在壽命上限。一些研究人員稱，人類的自然「過期日期」為125歲。日本的都千代是目前最知名的壽星，她活了117歲，而雅娜·卡爾芒的壽命為122歲，是壽命最長的人。她已在1997逝世。

In the UK, the number of people over the age of 100 has more than doubled since 2002, and could reach 36,000 by 2030. If there is a mortality plateau, by the year 2300 the oldest person alive could be about 150 years old.

自從2002年以來，英國壽命超過100的人增長了一倍，到2030年，3萬6千名英國人的壽命將超過100歲。如果「死亡高原」真的存在，那麼到2300年，最長壽的人的年紀將達到150歲。

Pleasure versus pain

樂趣多於痛苦？

Would a maximum lifespan of 150 make our lives better or just longer? One way of thinking about this is in terms of pleasure and pain: the more pleasure (and the less pain) we have over the course of our lives, the better our lives are. Other things being equal, a life which lasts 100 years is better than one that lasts 80 years, as long as the extra 20 years contain more pleasure than they do pain.

如果你能活到150歲，我們會不會因為長壽而變得更開心？其中一種衡量方式是對比快樂和痛苦程度：在我們的生活中快樂越多（痛苦越少），我們的生活就越好。在其他條件都相同的情況下，只要多餘的20年帶給我們的是開心而不是痛苦，那麼活到100歲的人會比80歲的人更幸福。

How likely an outcome is this? As people age, they are much more likely to develop degenerative conditions that could lead to a lower quality of life. But these conditions can be mitigated by a healthy lifestyle and adequate support services. While elderly life may be restricted in some ways, there is no reason that it cannot be, on balance, pleasurable.

在人們變老的時候，他們的各項功能會退化，致使生活質量更低。但是當他們追求健康飲食，擁有足夠的支持服務時，這種狀況會緩和很多。總而言之，在老人能在許多方面進行我們約束時，他們的快樂感會更高。

On the other hand, an extended lifespan might influence our earlier quality of life. In 2017, there were about 3.5 people of working age (16-64) for every person over age 65, but this ratio is expected to fall to 2.1 to one by 2040.

另一方面，壽命的延長可能會影響我們早期的生活質量。2017年，在超過65歲的人群中，每3.5個人中有一個屬於工作年齡段（16-64歲）的人，到2040年，這個比例有望降至2.1。

An anti-aging pill is still a long way off

抗衰老葯仍在研製中

This means that there will be relatively more people claiming pension benefits, and fewer people in the workforce paying taxes to support them. This could lead to the working population being required to pay additional taxes and remain in the workforce for longer, or a reduction in other services to cover pension costs.

這意味著有很多的人還在領著養老金，而繳稅的人變得越來越少，勞動人口需要繳更多的稅， 工作時間也會相應的延長，國家或減少服務項目減少以支付養老費用。

An unwanted postscript

沒人需要的附言

We might also think that our lives go better when we get the things we want. Having a longer life might give us more time to accomplish our goals and projects. But we might also think that a desirable life is one with a certain narrative structure.

當我們得到我們所需要的東西時，也會認為我們的生活會更好。更加長壽讓我們有更多的時間完成我們的目標和項目。但是我們可能也認為，理想的生活中會有更多的故事。

The late philosopher Ronald Dworkin distinguished between "experiential interests" and "critical interests" to shed light on how people may view their life goals. Experiential interests are for things like pleasure -- anything we enjoy. Critical interests are those what we value becoming a reality -- essential to what we think constitutes a good life. This could be a parents interest in the happiness of their child, for example.

已故哲學家羅納德·德沃金給「體驗式興趣」和「關鍵性興趣」划了一道界限，以闡明人們對生活目標的看法。體驗式興趣是有關享受的事情，可以是任何享受的事情。關鍵性興趣是人們對現實的考量，比如對過好生活有著至關重要的作用的事情。

We can imagine a person having a critical interest in avoiding the perceived indignity of dementia, which may accompany extreme old age. Even if the person doesnt seem bothered by their cognitive decline in the moment, this may not have been how they wanted their life to go. We might think it would be better for this person, taking the whole of their life into account, if they had died prior to this period of decline.

我們能想到，一個人在培養關鍵性興趣的情況下，將可以有效預防老年痴呆。即使他的認知能力暫時沒有下降，不可能以後也不會下降。如果我們在認知能力下降前死亡的話，我們會認為人們應該維持好他身體各個方面的健康也是很重要的。

Why sex gets better in older age

為什麼老年性生活質量更高？

In other words, there could be many circumstances in which we might live for too long. Sometimes it might be better for us to die earlier than we otherwise might have, if doing so is more consistent with the "life story" we wanted for ourselves -- for example, being active and independent throughout our lives.

換言之，有可能我們會活得過長。如果死亡能讓我們的「生活故事」更加連貫—例如，我們能在生活中保持活躍和獨立的狀態，有時早點死亡會比長壽更好。

Declining desires?

需求會減少嗎？

A similar concern has been raised by the late philosopher Bernard Williams. Williams argued that the things which give meaning to our lives are "categorical desires", which are essential to our identity. They include things like writing a novel, raising children or pulling off a charity project. These sit alongside more "meaningless" desires, such as the need for food or sex, which he argued cant make us happy in the long run.

已故哲學家伯納德·威廉姆斯也提出過類似的問題，威廉姆斯稱，「分類需求」讓我們的生活變得更有意義，讓我們找到自我。這些事情包括寫小說、養育孩子或做慈善工作。這些尋求食物或性等沒有意義的需求的人的快樂不會長久。

Williams believed that, if we live long enough, we will fulfil all our categorical desires -- losing an important driver of our happiness. We are then faced with a remaining life of oppressive boredom, or replacing our fundamental desires and radically changing who we are.

威廉姆斯認為，如果能活得夠長的話，我們會實現所有的分類需求，失去讓我們快樂的驅動力。我們在餘下的生活中會變得壓抑和無聊，或者我們的基本需求會發生改變，最終我們的本性會發生很大改變。

However, as I see it, life can remain rich and complex even for the very elderly, and taking on new projects need not undermine who we are. This is especially true if our friends and loved ones are living longer as well. While our desires and interests may change, connection to others can help to promote continuity among the various stages of our lives.

然後，在我看來，老年人的生活還是會很豐富和複雜，出現新的事物，而且它們也不會讓我們的本性發生改變，在我們所愛的人活得更長時，尤其如此。當我們的需求和興趣發生改變，我們和其他人的聯繫將能使我們在生活中的各個階段保持性格一貫性。

What each of these views shows is that living longer does not in itself make us better off. As our population continues to age, we will need to make important and potentially difficult choices about how we want to care for the elderly. Crucially, strategies to promote healthy ageing may not only ease the burdens on society, but help to ensure that our longer lives are better lives -- even in a philosophical sense.

我們每個人看到的東西是，活得更長本身並不會讓我們更幸福。隨著人口繼續老齡化，我們需要做出跟養老有關的重要、更難的選擇。關鍵的是，提高健康老齡化不僅能減少社會的負擔，從哲學的意義上來說，還能讓我們在活得更長的同時變得更幸福。

source：A philosopher asks: Is a longer life a happier one?