puzzles This multiple choice probability puzzle has been causing arguments for years Mark Frauenfelder
Sex Can time travelers go back in time and have sex with themselves? Astrophysicists investigate. Thom Dunn
brain teasers Saturday morning mind-benders: "Newcomb's Problem" and "Parfit's Hitchhiker" dilemma Mark Frauenfelder
game theory How "God Makes God" is a 1993 CD-ROM about probability, game theory, genetic algorithms, and evolutionary strategies Mark Frauenfelder
mathematics New research: There's a 50-50 chance we're living in a simulation and here's how to find out David Pescovitz
late stage capitalism The paradox of good government: the best stuff works well and is thus unnoticeable (and therefore easy to sell off) Cory Doctorow