metaphor had its origin in the Middle East, where camels are still used as beasts of burden. The camel is expected to carry straw that is harvested. There is a limit to how much straw a camel can carry. Every camel’s back has a breaking point. The difference between a tolerable burden and one that crushes may be a single piece of straw. I don’t know how much straw a camel can carry. I don’t know how heavy a burden I can carry. We all have a tendency, however, to suppose that we can carry far less