Eighty percent of adults in the US and the UK are moderate users of the caffeine.
80%的美国人和英国人都在一定程度上是咖啡因的使用者。

Of all the effects it has on our minds—enhanced attention and vigilance—perhaps least known is its tendency to make us more susceptible to persuasion.
咖啡因的作用中，我们熟知的是它能让我们集中精神、提高警觉——但是很少人知道咖啡因能让我们更容易被人家说服。

Before the attempt to change their minds, half the participants were given moderate doses of caffeine, while the other half took a placebo. Both groups were double-blinded so that neither the researchers nor the participants knew who had taken what. Then they were given six stories to read which argued against euthanasia.
在实验开始前，参加实验的人员被分成两组，让其中一组人食用中度剂量的咖啡因，而另外一组则是安慰剂。这次试验是双盲实验，也就是说不论是研究者还是参与者都不知道参与者到底服用的是哪种物质。然后给实验参与者读6个关于反对安乐死的故事。

When asked afterwards for their attitude to voluntary euthanasia, those who had drunk caffeine were more influenced by the persuasive message than those who'd had the placebo.
读完之后，向参与者询问他们对自愿安乐死的态度，结果显示那些喝了咖啡因的人比没有喝的人耳根子更软。

But why? What is it about caffeine that opens us up to persuasion?
但是这是为什么呢？咖啡因是怎样让我们更容易被劝服的呢？

The reason that a lot of persuasive messages pass us by is simply that we're often not paying much attention to them; our minds easily wander and we prefer not to think too hard unless it's unavoidable.
原因就是我们喝过咖啡之后，我们不会花太多心思去注意这些劝说性的信息，很轻易的就会接受它们；我们的思想很轻易就陷入一种迷茫状态，能不思考就不思考。