这个危地马拉人今年41岁，已经三次改变世界

今年是路易斯·冯·安在地球上度过的第41个年头，这个世界也因为他有过三次改变，然而他仍然因为其第一次对世界的改变而饱受批评。

这个发明于2000年在雅虎首次面世，有着各种各样的名字。这位危地马拉出生的计算机科学家将其称为“完全自动化的公共图灵测试，旨在将计算机与人类区分开来”，或简称“验证码”（Captcha）。或许你还记得，验证码这个小方框通常让人们感到十分恼火，里面是一些拉伸、扭曲的字母，人们必须正确识别并重新输入之后才能够获得某些网站的访问权限。路易斯·冯·安称，正是因为这一发明，一些陌生人在多个场合对他抱怨说：“哦，天哪，我恨你。”

尽管验证码可能引发了短暂的焦虑，但它们长期以来在防范反社会人士（直到最近，其光学阅读器对此类变形字体的识别率才有所好转）方面发挥了有效作用，这些人会使用计算机迅速买光Ticketmaster网站上的门票，注册数百万个邮箱账号以及从事一系列其他制造网络垃圾和行骗事件。

不幸的是，验证码也耗费了无数的运行时间（尽管每一次只有10秒的间隔），因为使用者得费力地去辨识这些字体。因此路易斯·冯·安想，人们在这10秒内是否可以做些更有意义的事情呢？答案是ReCaptcha，它对验证码测试进行了巧妙的调整，这样，网页浏览者实际上在解读古抄本难认词汇的同时证明了自己并非是机器人。借助ReCaptcha，路易斯·冯·安采用众包的方法来解读那些遗失的文献，每一天的解读量达到了3500万个词。谷歌于2009年收购了ReCaptcha。路易斯·冯·安如今是卡内基梅隆大学的顾问教授，曾经获得麦克阿瑟“天才”奖奖金。

这又把我们带到他在2011年的第三个发明，路易斯·冯·安和他在卡内基梅隆大学的研究生学生瑟维林·海克打造了Duolingo公司，该公司在《财富》杂志“改变世界的公司”2019年榜单上位列第36名。这个免费的语言学习应用程序是一个靠广告支持的项目（也有付费版本）目前已经有2800万活跃用户，它再次巧妙地让人们能够利用闲暇时光做一些有价值的事情：获得讲一门外语的能力。在这一过程中，他们也在帮助挽救少数濒临灭绝的语言。在Duolingo教授的36种语言中，有三种（夏威夷语、纳瓦霍语和爱尔兰语）都面临着成为历史的危险。例如在爱尔兰，每天讲爱尔兰语（盖尔语）的人口不到7.5万；如今，440万崭露头角的多国语言学习者正通过该应用程序在Duolingo上学习labhair（爱尔兰语：交谈）。当新人意识到其开发者是路易斯·冯·安时，他们对他说：“哦，天哪，我爱你。”

幸运的是，路易斯·冯·安和他的团队将有能力继续收获这份厚爱：Duolingo今年的营收预测为8600万美元，是2018年3600万美元的两倍多，而且他预计销售额在明年将翻番。反过来，这一增幅也让这位多产的发明家有财力寻找更好的方式来帮助学习语言，并为他的下一个项目提供资助：教授人们如何阅读。

我们的第五年度“改变世界的公司”榜单（是《财富》杂志众多基准榜单中我最喜欢的一个榜单）将展示大量致力于寻找可持续发展（通常也是盈利的）方式来解决社会挑战的企业。与以往一样，我们并没有按照“好”或“坏”的标准来衡量这些公司，我们也不会这样做，而且我们并不是在说，我们所凸显的项目能够抵消这些公司可能正在开展的不利于社会的事情。（财富中文网）

本文另一版本登载于《财富》杂志2019年9月刊，标题为《转化成功》。

译者：Feb

In his 41 years on earth so far, Luis von Ahn has changed the world three times. People still blame him for the first.

That invention, which had its public debut on Yahoo in 2000, had a mouthful of a name; the Guatemalan-born computer scientist called it a “completely automated public Turing test to tell computers and humans apart,” or “Captcha” for short. Captchas, you’ll recall, are those often--agonizing boxes of stretched and twisted letters that mortals must correctly identify and retype to gain access to certain websites. That invention, says von Ahn, has on multiple occasions provoked strangers to tell him, “Oh, my God, I hate you.”

For all the fleeting angst they may have caused, though, Captchas have long been effective in preventing antisocial types from using computers—whose optical readers, until recently, had trouble reading such misshapen type—to rapidly buy up tickets on Ticketmaster, sign up for millions of email accounts, and do a host of other spammy and scammy things.

Captchas also unfortunately have consumed countless hours of exertion (albeit in 10-second intervals) as users strain to decipher the characters. So von Ahn, now a consulting professor at Carnegie Mellon and winner of a MacArthur “genius” grant, wondered, What better thing could people do with that same 10 seconds of effort? The answer was ReCaptcha—which ingeniously tweaked the Captcha test so that web surfers actually deciphered the hard-to-read text of ancient manuscripts as they proved they weren’t bots. With ReCaptcha, which Google bought in 2009, von Ahn crowdsourced the decoding of lost literature—by 35 million words a day.

Which brings us to invention No. 3. In 2011, von Ahn and one of his former graduate students at Carnegie Mellon, Severin Hacker, created Duolingo, No. 36 on Fortune’s 2019 Change the World list. Their language-learning app, whose free, ad-supported programs (and a paid option) are actively used by 28 million people, has once again mastered the art of converting human downtime into something valuable: the ability to speak a foreign tongue. In the process, they are helping save a few from extinction too. Among the 36 languages that Duolingo teaches, three—Hawaiian, Navajo, and Irish—were once in danger of fading into history. In Ireland, for instance, fewer than 75,000 people speak Irish, or Gaeilge, daily; today, 4.4 million budding linguists are learning to labhair on Duolingo. When new acquaintances learn that von Ahn built it, they tell him, “Oh, my God, I love you.”

Happily, von Ahn and his team can afford to keep being loved: Duo¬lingo’s projected revenues for this year are $86 million—more than double 2018’s take of $36 million—and he expects sales to roughly double again next year. The growth, in turn, has allowed the serial inventor to invest in finding even better ways to help people learn languages—and to fund his next project: teaching people how to read.

Our fifth annual Change the World package—my favorite of Fortune’s many benchmark lists—offers a rich supply of companies that are finding sustainable (and often profitable) ways to address societal challenges. As always, we’re not weighing companies on a scale of “good” or “bad”—we couldn’t if we tried. Nor are we suggesting that the projects we’re highlighting absolve companies of things they may be doing that aren’t beneficial for society.

A version of this article appears in the September 2019 issue of Fortune with the headline “Translating Success.”