Whether or not anyone else is reading the stuff I’m posting here, the spammers have discovered me. And I’m afraid that “comment spam” is not as amusing as the e-mail variety. I have therefore installed one of those annoying sentry programs that will ask for the answer to a trivial question before allowing you to post a comment. I’m choosing questions that I’m sure every reader of this blog will be able to answer instantly — things like, “Who published the first proof of the impossibility of trisecting an angle?” and “True or false: The present king of France is bald?” Please give it a try. If you have any trouble — and you’re not a spambot — e-mail me at firstname.lastname@example.org.
Update 2006-12-14: A few days ago I thought I had solved the comment-spam problem by other means, and so I turned off the interrogation. But the spammers are back, and so I have put the sentry on duty again. This time the questions all take the same form: a sequence of positive integers. You’ll be asked to name the next element of the sequence. None of them are tricky (no lists of subway stops), or even interesting. If the spambots learn to solve the problems in this set, well, good for them; at that point we can think about escalating to the next level.