If two things are correlated, there is causation. Either A causes B, B causes A, they have common cause, or they have a common effect you're conditioning on.
That's 28 words. Isn't it a bit long? (Still upvoted because the first sentence stands on its own with just 8 words.)
•It doesn't have to be 15 words long, it's just the best "15" words.
People want to tell everything instead of telling the best 15 words. They want to learn everything instead of the best 15 words. In this thread, instead post the best 15-words from a book you've read recently (or anything else). It has to stand on its own. It's not a summary, the whole value needs to be contained in those words.
I'll start in the comments below.
(Voted by the Schelling study group as the best exercise of the meeting.)