Can You Say Marginal Rate of Substitution?

Once, when my newborn son was barely back from the hospital, I was holding him in my arms with my wife looking on. I asked him, “Can you say marginal rate of substitution?” My wife recognized that as a bit of economics jargon and accused me of trying to turn our son into an economist like me. While it was said as a little joke between the two of us, the longer I teach and write, the more I seriously wish people actually thought in such marginal terms, because many of the times that we confuse ourselves and others are due to our failure to do so. FULL ARTICLE