18. Freakonomics FAQ, No. 1

19. Waiter, There’s a Physicist in My Soup! (Part 1)

20. Waiter, There’s a Physicist in My Soup! (Part 2)

21. Bring on the Pain!

22. Why Cities Rock

Pick of the Week: Are We in a Mattress-Store Bubble? (Ep. 251)

How to Be Happy (Ep. 345)

Two (Totally Opposite) Ways to Save the Planet (Ep. 346)

Pick of the Week: The Cheeseburger Diet (Ep. 230)

Pick of the Week: The Demonization of Gluten (Ep. 304)