In 1996,56 volunteers took part in a study to test a new pain killer called Trivaricaine.
1996年，56个志愿者参加了一项研究，测试一种名叫Trivaricaine的止痛药。
On each subject, one index finger was covered in the new painkiller while the other remained untouched.
每个实验对象的一个食指涂上这个新型止痛药，另一个食指保持原样。
Then, both were squeezed in painful clamps.
然后，两个食指都用钳子使劲夹住。
The subjects reported that the treated finger hurt less than the untreated one.
实验对象都表示那个涂了药的食指没有另一只疼。
This shouldn't be surprising, except Trivaricaine wasn't actually a painkiller, just a fake concoction with no pain-easing properties at all.
这本应该没什么好惊讶的，除了Trivaricaine本身并不是一种止痛药以外，它只是一个不含任何缓解疼痛成分的假混合物。
What made the students so sure this dummy drug had worked?
是什么让这些学生坚信这个假冒的药有效的呢？
The answer lies in the placebo effect, an unexplained phenomenon where in drugs, treatments, and therapies that aren't supposed to have an effect, and are often fake, miraculously make people feel better.
答案就是安慰剂效应，它是一种至今原因不明的现象，发生在使用那些本应该没有效果的药物、手术和治疗上，一般都是假的，却奇迹般地使人们感到好转。
Doctors have used the term placebo since the 1700s when they realized the power of fake drugs to improve people's symptoms.
医生们从18世纪开始使用安慰剂这个术语，那时他们开始意识到假药的作用能够改善病人的症状。
These were administered when proper drugs weren't available, or if someone imagined they were ill.
当合适的药品短缺时，他们会使用这种治疗方法，或者有些人幻想自己生病的时候。
In fact, the word placebo means "I shall please" in Latin, hinting at a history of placating troubled patients.
实际上，安慰剂这个词在拉丁语里是“我会好起来”的意思，暗示着安抚受病痛折磨的病人已有一段历史。
Placebos had to mimic the real treatments in order to be convincing, so they took the form of sugar pills, water-filled injections, and even sham surgeries.
安慰剂模仿真正的治疗以达到使人信服的目的，所以他们选择糖丸，注射水，甚至假手术的形式。
Soon, doctors realized that duping people in this way had another use: in clinical trials.
很快，医生意识到这样蒙骗人还有另一种用途：临床试验。
By the 1950s, researchers were using placebos as a standard tool to test new treatments.
直到二十世纪五十年代，研究人员将安慰剂作为一种标准工具来测试新的治疗方法。
To evaluate a new drug, for instance, half the patients in a trial might receive the real pill. The other half would get a placebo that looked the same.
例如测试一种新药，一半的临床病人可能会服用真的药丸，另一半则会服用看起来一模一样的安慰剂。
Since patients wouldn't know whether they'd received the real thing or a dud, the results wouldn't be biased, researchers believed.
药丸病人并不知道他们服用的是真药还是假药，因此，研究人员相信结果是准确的。
Then, if the new drug showed a significant benefit compared to the placebo, it was proved effective.
于是，如果这种新药比起安慰剂对病人有很明显的改善，那么这种新药就是有效的。
