Eighty percent of adults in the US and the UK are moderate users of the caffeine.
80%的美國人和英國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，我們熟知的是它能讓我們集中精神、提高警覺——但是很少人知道咖啡因能讓我們更容易被人家說服。

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.
在實驗開始前，參加實驗的人員被分成兩組，讓其中一組人食用中度劑量的咖啡因，而另外一組則是安慰劑。這次試驗是雙盲實驗，也就是說不論是研究者還是參與者都不知道參與者到底服用的是哪種物質。然后給實驗參與者讀6個關于反對安樂死的故事。

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.
讀完之后，向參與者詢問他們對自愿安樂死的態度，結果顯示那些喝了咖啡因的人比沒有喝的人耳根子更軟。

But why? What is it about caffeine that opens us up to persuasion?
但是這是為什么呢？咖啡因是怎樣讓我們更容易被勸服的呢？

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.
原因就是我們喝過咖啡之后，我們不會花太多心思去注意這些勸說性的信息，很輕易的就會接受它們；我們的思想很輕易就陷入一種迷茫狀態，能不思考就不思考。