This article about spurious correlations is an interesting reminder that not all correlation amounts to causation, like the this one which correlates imports of crude oil into the U.S. From Venezuela and the per capita consumption of high fructose corn syrup. This is, of course something one needs to keep in mind while taking notes, though it usually is so obvious as not to need pointing out. But it's not always obvious, so I reminder might be somewhat useful.
I consider the connection between the use of steel nibs and the lack of creativity in writing to be spurious, for instance.
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