This week we talk to a researcher who has determined the key to happiness is talking to strangers on the subway. (We do not talk to him on the subway.) Also, we learn how curse words might make you stronger. All that plus filmmaker John Waters joins us to take our personality test.

How Long Can You Dunk?

Paula Poundstone is on a quest to gather all of the world's knowledge. Or, as she puts it, "to get less stupid, one topic at a time." Follow her search as she looks to scientists, researchers, and experts for evidence about everything from what music cats like to the fluid dynamics of spilling coffee. "Every week, we'll keep looking for knowledge," says Paula, "because we know we left it somewhere."