There is a fun parlour game, as we British call such things, to play on slow days like New Year’s Day: The Two Things. This is to try to distill the essentials of some skill or field down to the only two things that you truly need to know. For example, civil engineering becomes 1.) Dirt and 2.) Dirt plus water is mud – and there is always mud. Boxing is 1.) Hit and 2.) Don’t be hit.

Economics becomes 1.) Incentives matter and 2.) Opportunity costs. Grasp those two properly and you’ll know more than most in the profession and definitely more than any politician.