Dr Herbert West (1357769) writes "The phrase "correlation != causation" goes back to 1880 (according to Google Books). However, the use of the phrase has increased exponentially starting 1990's-200's, and is becoming a quick way to short-circuit certain kinds of arguments.
In the late 19th century the British statistician Karl Pearson introduced a powerful idea in math: that a relationship between two variables could be characterized according to its strength and expressed in numbers. An exciting concept, but it raised a new set of issues-- how to interpret the data in a way that is helpful, rather than misleading.
When we mistake correlation for causation, we find a cause that isn't there, which is a problem...however, as science grows more powerful and government more technocratic, the stakes of correlation—of counterfeit relationships and bogus findings—grow larger."
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