I like maple syrup because it is a great metaphor. (OK, I also like it because it is sweet and flavorful, because it goes great on pancakes, oatmeal and ice cream, and because they make large amounts of it near our summer place in northern Ontario.) But the thing I like to talk about with maple syrup is that it takes 45 liters of maple sap to make 1 liter of syrup. It’s a metaphor of concentration, ...