甚至专家也会犯错
历史记录了大量专家意见是错误意见的时刻。在古时候，标准的医疗意见是，头疼是头盖骨里面的恶魔导致的。被采用的治疗方法从打开头盖骨放走恶魔，到服用从牛大脑和山羊大便中提取的药物（有些美洲原始部落选择河狸的睾丸）。
在十八世纪初期，美洲殖民地有人提出通过注射疫苗的方法治疗类似天花这些疾病时，绝大多数权威都认为这毫无意义。他们中间有本杰明富兰克林和后来创立了哈佛医学院的一些人。和权威作对的人玻尔斯顿（ Zabdiel Boylston）是一个相对不那么出名的人，他甚至没有医学学位。谁的意见被证明是正确的？不是专家，而是玻尔斯顿。
1890年，诺贝尔奖获得者，细菌学者罗伯特科赫（Robert Koch）报告说，他发现了一种能治愈肺结核的物质。但是，到当这种物质被注射给病人后，发现它加重病情，甚至死亡。
在1904年，心理学家斯坦利霍尔（Stanley Hall）发表他的专业观点，当女人从事精神紧张的工作，特别是和男人在一起时，她们会丧失乳房功能和对母性的的爱好，同样的就会降低生育能力。如果随后她们生育了孩子，这些孩子更容易得病。今天，这样的观点就非常可笑了。
在1919-1922年间，纽约大都市艺术博物馆购买了17个黄金容器，专家们鉴定它们是3500年前埃及坟墓里出土的宝藏。在1982年，人们发现这些容器是二十世纪的赝品。
在1982年，发明了一种叫做胶质二氧化杜的药物，并用来清晰身体内器官的轮廓，这样就能得到更清晰的X光照片。19年以后，医生发现即使很小的剂量也会导致癌症。
在1959年，一个叫反应停的镇静剂出现在市场，很多内科医生将它开给孕妇。然后，当很多畸形儿出生后，医疗机构认识到反应停是罪魁祸首。
在1973年，使用精确的雷达测绘技术，科学家们认为他们早些时候声称的金星表面的观点是错的。它不是他们所认为是光滑的，而是布满了火山口的坑坑洼洼。
在十九世纪80年代和90年代之间，在出版社和学术界有一个非常热门话题是互相依赖性。任何一个和酗酒者或者嗑药者都被认为对这个问题有推波助澜的作用，主要是通过无意识地鼓励这些人的习惯或者使他们沉溺其中而产生。很快，这个互相依赖的观点成为任何失控行为特征情况的诊断选择。有依赖性的人被敦促购买书籍，参加学术讨论会，和他们家庭中问题成员一起接受咨询。后来，一位好奇的研究者（Edith Gomberg），检查了这个运动建立的科学研究基础。她发现……什么也没有，不存在，没有。用她的话说，“没有调查，没有临床研究，没有诊断；只有描述，仅凭印象的陈述。”
在二十世纪大多数时候，普遍被接受的科学观点是胃溃疡是由于压力产生的胃酸过多导致的。后来，巴里马歇尔（Barry Marshall）证明了，胃溃疡是由细菌引发的，并且可以被抗生素治愈。
还记得《侏罗纪公园》中雷龙的脑袋伸长到树顶的镜头吗？这个镜头反映了大型恐龙吃离地面三十英尺以上树叶的传统科学观点。然而在1999，迈克尔帕丽斯（Michael Parrish）通过大型恐龙颈骨计算机模型的方式做实验，发现恐龙永远不能将他们的头抬起来超过他们身体的水平。如果他们这样做，他们脖子的椎骨会垮掉。他们同样无法用他们的后腿站立，因为这样对他们的血压要求太高了。
很多年来内科医生告诉我们，纤维素能够降低胆固醇并且预防结肠癌。最后，医药研究表明，它不会降低胆固醇。随后，研究者证明它也不会预防结肠癌。
直到现在，很多专家确信犯罪的原因是糟糕的社会环境，解决方法就是投入百万美元到贫穷的街区开展不同的社区事业。其他的专家同样程度的相信犯罪的原因是情绪紊乱，而这只能通过心理咨询治疗。但是著名研究员斯坦顿塞米诺（Stanton Samenow）反对这两个观点。塞米诺争辩说，“糟糕的社区、不称职的父母、电视、学校、毒品或者失业”不是犯罪的原因——犯罪者自己才是。他们违反法律不是因为环境迫使他们这样做，而是他们选择这样做，他们这样选择是因为他们认为他们自己是特殊的，可以凌驾于法律之上。在塞米诺看来，罪犯恢复正常生活的关键是他们要为他们行为的后果承担责任。塞米诺是对的吗？时间会分辨。
我们无法知道我们这个时代哪些专家的意见会被未来的研究者推翻。但是我们肯定有一些一定会被推翻。而且他们在今天看来是毫无破绽的。
原文：
Even Experts Can Be Wrong
History records numerous occasions when the expert opinion has been the wrong opinion. In ancient times the standard medical opinion was that headaches were caused by demons inside the skull. The accepted treatment ranged from opening the skull and releasing the demons to giving medicines derived from cow’s brain and goat dung. (Some Native American tribes preferred beaver testicles.)4
When the idea of inoculating people against diseases such as smallpox first arrived in the colonies in the early 1700s, most authorities regarded it as nonsense. Among them were Benjamin Franklin and a number of the men who later founded Harvard Medical School. Against the authorities stood a relatively unknown man who didn’t even have a medical degree, Zabdiel Boylston. Whose opinion was proved right? Not the experts’ but Zabdiel Boylston’s.5
e–winning bacteriologist, Dr. Robert Koch, reported that he had found a substance that would cure tuberculosis. When it was injected into patients, though, it was found to cause further illness and even death.
In 1904 psychologist G. Stanley Hall expressed his professional opinion that when women engage in strenuous mental activity, particularly with men, they experience a loss of mammary function and interest in motherhood, as well as decreased fertility. If they subsequently have children, the children will tend to be sickly.6 Today this idea is laughable.
Between 1919 and 1922 the Metropolitan Museum of Art in New York City bought seventeen gold vessels that experts determined were authentic treasures from a 3,500-year-old Egyptian tomb. In 1982 the vessels were discovered to be twentieth-century fakes.7
In 1928 a drug called thorotrast was developed and used to outline certain organs of the body so that clearer X-rays could be taken. Nineteen years later, doctors learned that even small doses of the drug caused cancer.
In 1959 a sedative called thalidomide was placed on the market. Many physicians prescribed it for pregnant women. Then, when a large number of babies were born deformed, medical authorities realized that thalidomide was to blame.
In 1973, using refined radar mapping techniques, scientists decided that their earlier claims about the surface of Venus were wrong. It was not smooth, as they had thought, but pockmarked with craters.8
In the 1980s and 1990s one of the hottest topics in the publishing and
seminar industries was co-dependency. Anyone related to an alcoholic or drug addict was considered to be a contributor to the problem, chiefly by unconsciously encouraging the person’s habit or enabling the person to indulge it. Soon the idea of co-dependency became the diagnosis of choice for any situation characterized by out-of-control behavior. Co-dependents were urged to buy books, attend seminars, and join their troubled family member in counseling. Then one curious researcher, Edith Gomberg, examined the scientific research base on which the movement was founded. She found . . .zip, nada,nothing. In her words, “There are no surveys, no clinical research, no evaluations; only descriptive, impressionistic statements.”9
For most of the twentieth century, the universally accepted scientific opinion was that stomach ulcers are caused by excess stomach acid generated by stress. Then Barry Marshall demonstrated that ulcers are caused by bacteria and can be cured with antibiotics.
Remember the brontosaurus with his head stretching to the treetops in Jurassic Park? That scene reflected the traditional scientific opinion that the big dinosaurs dined on leaves thirty or more feet off the ground. In 1999, however, Michael Parrish, a northern Illinois researcher, experimented with a computer model of the neck bones of large dinosaurs and discovered that they could never have lifted their heads above the level of their bodies. If they had, their neck vertebrae would have collapsed. They couldn’t have stood on their hind legs, either, because the demands on their blood pressure would have been excessive.10
For years physicians told us that fiber lowers cholesterol and protects against colon cancer. Eventually, medical research established that it doesn’t lower cholesterol. Then researchers demonstrated that it doesn’t protect against colon cancer.11
To this day, many experts are convinced that the cause of crime is a bad social environment and that the solution is to pour millions of dollars into poor neighborhoods for a variety of social programs. Other experts are equally convinced that the cause of crime is an emotional disorder that can be cured only by psychological counseling. But a leading researcher, Stanton Samenow, disputes both views. Samenow argues that “bad neighborhoods, inadequate parents, television, schools, drugs, or unemployment” are not the cause of crime—criminals themselves are. They break the law not because conditions force them to but because they choose to, and they choose to because they consider themselves special and therefore above the law. In Samenow’s view, the key to criminals’ rehabilitation is for them to accept responsibility for their behavior.12 Is Samenow correct? Time will tell.
It is impossible to know what expert opinions of our time will be overturned by researchers in the future. But we can be sure that some will be. And they may well be views that today seem unassailable.