The This-Isn't-Possible Smell Test

From time to time I come across a problem that I don&rsquo;t know how to solve but that I&rsquo;m certain someone else must have already solved. One of the benefits that experience brings is that it&rsquo;s relatively safe to make the inference that if a problem seems interesting or important, someone else has already taken a whack at it publicly: it&rsquo;s a big internet out there, and in…