科学与数学launiusr.wordpress.com编辑精选
为什么要探索太空？1970 年写给非洲修女的一封信
Why Explore Space? A 1970 Letter to a Nun in Africa.
2012 — 2015，它一次次回到首页
黑点是上首页（≥ 50 分）的那次投稿，空心点是没冲上去的投稿，点越大分数越高。
导读
这篇页面是1970年NASA科学家Ernst Stuhlinger回复赞比亚修女Mary Jucunda的信，解释为什么在有人挨饿时仍值得投入太空探索。信中主张太空研究通过技术进步和知识增长长远惠及人类，并用镜头研磨工的故事说明科学发现常带来意外回报。
为什么经久不衰：它把“探索未知还是先解决眼前苦难”的经典争论讲得清晰而克制，至今仍是讨论科研公共投入价值的常被引用文本。
HN 评论精选
质疑单纯粮食援助的长期效果，强调要解决人口与粮食失衡的根源。
我不知这算不算残忍，但每当人们谈捐钱给非洲饥饿儿童，我总想象：每年捐款理论上能让一些孩子脱离饥饿，可他们长大后会生育，新增孩子数量几乎肯定高于最初救出的人数，于是饥饿儿童可能不减反增。所以问题应反过来：长期看，买食物捐给饥饿儿童如何改善非洲？是什么导致这些国家孩子多于食物？与其治标，正在做什么消除根源？
jxcole查看英文原文
I don't know if this makes me cruel, but whenever people talk about donating money to starving children in Africa, I always imagine the following: If I were to donate some amount of money to starving children in an impoverished nation every year I could, theoretically, bring some of them out of starvation. However, these children would then grow into adults, and then these adults would have children of their own. The number of these new children would almost certainly be higher than the number I originally helped bring out of famine, so at that point there would be just as many if not more starving children than we had to begin with. So in my mind the question really goes the other way, how does donating money to buy food for starving children in Africa improve Africa's condition in the long term? What problems caused these nations to produce more children than food and what is being done to eliminate the source of these problems, rather than just the symptoms?
批评反对者默认求知无内在价值，并指出社会对其他公共文化开支更宽容。
我发现反对太空探索与反对联邦资助科研共享一个基本假设：为知识而追求知识本身无价值；只有对活人有即时益处且不太贵才值得。未知知识的价值不可知，这点常被忽略。即便纯粹求知无用且挤占资源，社会也接受税金资助洁净公园、艺术、节日烟火等不必要之物；但人们更反感太空与科研，或许因为普遍科学素养低，把科学追求归入“抽象、大概无用”。
john_b查看英文原文
I've found that objections to space exploration share a fundamental axiom with the more general objections to federal funding of scientific activities of any type. Namely, that the pursuit of knowledge for its own sake is an inherently worthless activity. If that knowledge happens to have some immediate positive impact on a problem affecting presently living people, then it may be worth pursuing if such a pursuit isn't "too expensive". While it's trivially obvious that the value of unknown knowledge is unknowable, this doesn't often occur to such people, focused as they are on the limitations of the present instead of the possibilities of the future. Even if the pursuit of knowledge for its own sake were a completely useless activity which diverted resources away from more pressing problems, societies everywhere have accepted that their tax dollars inevitably fund certain things which are unnecessary. Clean parks, public support for the arts, city fireworks on holidays, etc. Yet people generally find these latter sinks of funding less objectionable than things like space exploration and federal support for science. Perhaps it's because the enormous scientific illiteracy afflicting the populace as a whole (which can be observed simply by reading any popular journalistic account of scientific developments) places scientific developments and scientific pursuits into some mental category of "abstract, probably useless stuff".
强调资金边际收益递减，并指出只针对太空的禁欲论很双标。
这些讨论常缺边际收益概念。钱最终是经济生产能力的抽象。多花一倍钱买食物可得一倍食物，但若全球食物支出翻倍，产量恐怕只增约30%。Givewell评估不只问效率，还问“若给更多钱能否有效花掉”。另一奇怪是选择性应用论证：常听“喂饱所有人前停止太空探索”，却几乎没听过“结束饥饿前停止拍电影”。
Symmetry查看英文原文
One thing I see missing from these discussions is the notion of diminishing returns. In the end money is an abstraction over the productive capabilities of our economy. If I were to spend twice as much money on food I could get twice as much. But if the world doubled it's expenditures on food I doubt food production would go up by more than 30% or so. If you read charity evaluations at Givewell they always ask "How efficiently are they spending their money" but they also ask "Could they efficiently spend more money if it was given to them." Another is that it seems odd how selectively we apply this argument. I often hear about the need to stop space exploration until everybody is fed but I don't think I've ever heard someone say we should stop making movies until we end hunger.
将信置于20世纪科学乐观主义中，指出现代对科学代价与收益的信心下降，但制度性再分配难题论点仍成立。
Stuhlinger的信体现现代尤其20世纪中期对科学的基本乐观，如今这种信念已黯淡。他们相信科学有泛化产生善的力量：在科学事业上投入相对小成本，很可能最终产生巨大具体益处。镜头研磨工的故事正体现这种期待。如今西方社会持有此信念的比例小得多：疗法常有严重副作用，机器有废物和危险，起初确定的知识常变得不那么确定。我们对科学成本低、收益大或必然的信心都减弱了。他关于民主官僚国家重新分配科学经费并不简单的论点仍有力，但“只要做雄心勃勃的科学就会带来巨大善”的底层假设更难成立。
putzdown查看英文原文
Stuhlinger's letter expresses a basic optimism toward science that was characteristic of the modern era in general and the middle of the 20th century in particular, and which has tarnished a great deal since then. Their faith held that science has a sort of generalized power to produce good; more specifically, that given a relatively small cost investment (in terms of money, time, effort, attention, education, etc.) in scientific endeavor, a very large and concrete benefit is likely to eventually result. His story of the lens grinder captures that expectation. Without arguing the case, I think it's fair to say that a much smaller proportion of the people in Western societies (at least) now hold this faith as strongly. The costs of modern "progress" have become more apparent over time: cures often harbor severe side effects; machines have their wastes and their dangers; knowledge that seems sure at first often proves less sure with further study. Our confidence that the costs of science are as low as we once thought they were has weakened; our confidence that the benefits are as great or as inevitable has also declined. His argument that reapportioning money from science to humanitarian causes is not as simple, in a democratic, bureaucratic country, as it seems it should be is still as strong as it was when he gave it, if not more so. But the underlying assumption that, "If we just do something ambitiously scientific, vastly great goods for humanity will result," is harder to sell than it was. We no longer accept that a manned voyage to Mars (for example) will result in concrete benefits for humanity in a way that is remotely analogous to the support of a lens grinder at the dawn of optics. Proponents of space exploration must continue to both show the rest of us the concrete benefits of investment and, at the same time, limit their expectations. It will never again be like it was in the 60s and early 70s.
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