Jack and I, fresh from the lab, yarn with renowned evolutionary psychologist Robin Dunbar. We figure out why, if Robyn arrived on a donkey, Jack would of course assist Robyn (as Jack's senior) off the donkey. But then, if the roles were reversed, would Robyn be obliged to help Jack off a donkey? Stick around for all these ancient lessons and more, from why a reputation-based economy might be a bad idea, to how come I cried when Dolph Lundgren passed away, when I hadn't seen the fella since Rocky 4? And of course, the ultimate question of civilisation - can anything ever be good again after being scaled beyond the local? It's all in the numbers.