Coffee is so ubiquitous that it’s easy to forget how unusual it is.

Its defining, namesake ingredient, caffeine, is not only the world’s most popular mind-altering drug—used regularly by perhaps 90% of the planet—but also, as Michael Pollan has noted, the only one we routinely serve to children. This nearly universal acceptance is all the more striking considering that, for much of its 500-year history, coffee drinking was viewed with confusion, suspicion and disgust.

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