Why are people who can't remember their past also unable to picture their future? Why do we get so anxious about the world changing around us? What should you advise the president if we find ourselves at war with extraterrestrials? And what does this have to do with Wayne Gretzky, or the Greek goddess of memory, or hitting a bottle to get ketchup onto your French fries? Join this week's episode to find out about one of the most important things brains do: simulations of possible futures.