As his book A Mathematician Plays the Stock Market unfolds, Temple University math professor John Allen Paulos pledges to abstain from stock tips and investment advice, the “financial pornography” that is the currency of so many how-to guides. Instead, he offers mathematical and psychological theories about the forces that influence the behavior of investors and markets, illustrating his lessons with quips about beauty pageants, cows, and the behavior of ants, and a parable about a society wherein a matriarch (an analogue for the SEC) dispenses information about philandering men. But for all his brainpower, Paulos is humble. He shares some of the confusion and frustration of armchair investors—he writes of his own bad experience with WorldCom stock—and cautions the reader that, if it’s now possible for someone to muster the technological and mathematical wherewithal to outthink the market, “it’s not likely to remain so for long.” Paulos explains it all at 7 p.m. at Olsson’s Books & Records, 1200 F St. NW. Free. (202) 347-3686. (Joe Dempsey)