Counter Factuals

Sheldon and  Amy have create a game called "Counter-Factuals," where they postulate a difference in the world that currently doesn't exist and pose questions to each other. The game can only be played by them because it requires that you know how the other person thinks thus proving that they are very compatible together. Leonard tries the game and fails miserably. Asked that in a world where mankind is ruled by a giant, intelligent  beaver, what food is no longer consumed? Leonard’s answer is  cinnamon, but the correct one is  cheese Danish. Since the people would build many dams to appease their overlord and flood the city of  Copenhagen, devastating the Danish people enough to never invent their namesake pastry. Sheldon and Amy offer to play hide and seek with him.