What is the tragedy of the commons? - Nicholas Amendolare

翻译人员: Chien Yet Chong

“大众共同拥有的往往却是最被忽视的。” ——亚里士多德，《政治学》

Imagine as a thought experiment that you live in a small village

有这样一道思考题， 假设你住在一个小村庄里，

and depend on the local fish pond for food.

村民们依靠在当地鱼塘打渔为食。 你要与另外三位村民共享这个鱼塘。

You share the pond with three other villagers.

The pond starts off with a dozen fish, and the fish reproduce.

鱼塘自起始时有十二条鱼， 同时鱼也会繁殖。

For every two fish, there will be one baby added each night.

每两条鱼每晚会产出一条小鱼。

So, in order to maximize your supply of food,

那么为了最大化你们的食物供给，

how many fish should you catch each day?

你们每天可以捕多少条鱼呢？

Take a moment to think about it.

让我们花点时间思考一下。

Assume baby fish grow to full size immediately

假设大鱼每晚产下的小鱼 在次日就会变为大鱼，

and that the pond begins at full capacity,

鱼塘自起始时也有 足够的条件供鱼类生息，

and ignore factors like the sex of the fish you catch.

同时忽略鱼的性别， 以及类似的影响因素。

The answer? One, and it's not just you.

答案是一条， 而且不仅仅是你只能打一条鱼。

The best way to maximize every villager's food supply

最大化每位村民 食物供给的方法就是，

is for each fisherman to take just one fish each day.

每位渔民每天只能捕一条鱼。

Here's how the math works.

算法是这样的。

If each villager takes one fish, there will be eight fish left over night.

如果每位村民每天打一条鱼， 当晚鱼塘内会剩下八条鱼。

Each pair of fish produces one baby,

每两条鱼会繁殖出一条小鱼，

and the next day, the pond will be fully restocked with twelve fish.

于是次日，鱼塘内鱼的 数量又会恢复到十二条。

If anyone takes more than one, the number of reproductive pairs drops,

如果有任何一位多捕了一条， 鱼塘内的繁殖对数量就会减少，

and the population won't be able to bounce back.

鱼的数量也就无法恢复， 无法维持正常供给。

Eventually, the fish in the lake will be gone,

最终鱼塘里也就不再有鱼了，

leaving all four villagers to starve.

而村民们只能挨饿。

This fish pond is just one example of a classic problem

这个鱼塘引发的问题， 只是这类问题的一个示例，

called the tragedy of the commons.

即所谓的“公用品悲剧”。

The phenomenon was first described in a pamphlet

这个现象首次于1833年

by economist William Forster Lloyd in 1833

由威廉·福斯特·洛伊提出， 发布在一本小手册上，

in a discussion of the overgrazing of cattle

以此讨论了在村庄的公共区域内

on village common areas.

过度放牧的现象。

More than 100 years later, ecologist Garrett Hardin revived the concept

一百多年后，经济学家 加勒特·哈丁再次提出了这个概念，

to describe what happens when many individuals

用来描述当许多人 共享一种有限的资源时

all share a limited resource,

会发生什么，

like grazing land,

比如共用牧场、

fishing areas,

鱼塘、

living space,

生活空间、

even clean air.

甚至是清新的空气。

Hardin argued that these situations pit short-term self-interest

哈丁认为造成这些 公共资源短缺的现象

against the common good,

是由于人们盲目追求短期自我利益，

and they end badly for everyone,

而这最终只会有害于所有人，

resulting in overgrazing,

导致过度放牧、

overfishing,

过度捕鱼、

overpopulation,

人口过剩、

pollution,

大气污染

and other social and environmental problems.

以及其他社会环境问题。

The key feature of a tragedy of the commons

“公用品悲剧“的主要特点是，

is that it provides an opportunity for an individual to benefit him or herself

它为人们提供了让自己获益的机会，

while spreading out any negative effects across the larger population.

同时却对大众造成负面影响。

To see what that means, let's revisit our fish pond.

想要进一步了解它的含义， 让我们回到之前的鱼塘思考题。

Each individual fisherman is motivated

每位渔民都有理由

to take as many fish as he can for himself.

为自己捕捞尽可能多的鱼。

Meanwhile, any decline in fish reproduction

然而同时鱼塘内 鱼的繁殖量下降

is shared by the entire village.

是需要所有村民一起承受的。

Anxious to avoid losing out to his neighbors,

急于避免自己的捕鱼量比邻居少，

a fisherman will conclude that it's in his best interest to take an extra fish,

渔民会为了个人利益 尽可能地多捕一条鱼，

or two,

或者两条，

or three.

或者三条。

Unfortunately, this is the same conclusion reached by the other fisherman,

不幸的是，每位渔民都是这样想的，

and that's the tragedy.

而这就是悲剧的开始。

Optimizing for the self in the short term isn't optimal for anyone in the long term.

自身短期的利益往往 与群体长期利益向冲突。

That's a simplified example, but the tragedy of the commons

以上只是一个简单的例子， 然而公用品悲剧

plays out in the more complex systems of real life, too.

也发生在现实生活中 更复杂的情形里。

The overuse of antibiotics has led to short-term gains in livestock production

过多使用抗生素可以增长 畜牧生产的短期收益

and in treating common illnesses,

并治疗一些人类普遍的疾病，

but it's also resulted in the evolution of antibiotic-resistant bacteria,

但同时也会引发细菌的抗药性，

which threaten the entire population.

从而对整个人口系统造成威胁。

A coal-fired power plant produces cheap electricity for its customers

依靠燃煤发电可以为人们 提供廉价的电力

and profits for its owners.

并使发电厂获利。

These local benefits are helpful in the short term,

这些诚然可以为当地发展 提供短期的利益，

but pollution from mining and burning coal is spread across the entire atmosphere

但采矿和燃煤造成的污染 则会遍布整个大气层，

and sticks around for thousands of years.

在几千年内都无法消失。

There are other examples, too.

这样的例子举不胜举。

Littering,

乱扔垃圾、

water shortages,

水资源短缺、

deforestation,

砍伐森林、

traffic jams,

交通堵塞，

even the purchase of bottled water.

甚至是购买瓶装水。

But human civilization has proven it's capable of doing something remarkable.

然而人类文明已经证明了 它可以做一些卓尔不群的事。

We form social contracts,

我们起草社会契约、

we make communal agreements,

我们制定公用协定、

we elect governments,

我们选择政府党派、

and we pass laws.

我们通过法律议案。

All this to save our collective selves from our own individual impulses.

这都是为了拯救因个人行为 而受损的集体利益。

It isn't easy, and we certainly don't get it right nearly all of the time.

这并不是简单的事， 而我们也没有经常做对。

But humans at our best have shown that we can solve these problems

但当人类怀有最好的意愿时， 我们总是可以解决这些问题，

and we can continue to do so if we remember Hardin's lesson.

如果我们能铭记哈丁的这个理论， 就能继续做正确的决定。

When the tragedy of the commons applies,

当公用品的利益出现时，

what's good for all of us is good for each of us.

对大家都有益的， 才是对每个人有益的。