From Scientific American, the economist has no clothes: Unscientific assumptions in economic theory are undermining efforts to solve environmental problems; and brother, can you spare me a planet? Robert Nadeau on mainstream economics and the environmental crisis. Scientists know better than you, even when they're wrong: Why fallible expertise trumps armchair science—an interview with Harry Collins. Should philosophy have something to say to non-philosophers? Should philosophy be pursued only by those trained in philosophy? Cogito poses some big questions to four British and US philosophers. US presidential elections are suspiciously like high school popularity contests, er, elections — it's not who you know, it's who knows you. In pursuing the convenience of a Web 2.0 world, we are consenting to being incorporated into a finely tuned marketing machine, with ever more subtly adapted gears, to our meet our needs — manufactured and otherwise. Game Google, help the world: Why search-engine optimization makes the Web a better place. From TED, Paul Stamets on 6 ways mushrooms can save the world. Edward Rothstein on LSD, a mind-altering drug that altered a culture as well. Belles and tolls: Horse racing, like art and life, comes with tragedy built-in. War of the Babies: When modern warfare and demography square off, demography wins.