Are homo economicus and homo politicus identical twins?

When we view social and economic cooperation through the lens of game theoretic strategic interaction, we find that they have essentially identical abstract representations. If instead we view them substantively according to the issues with which they deal, they are commonly different. But even while they are substantively different, they depend heavily on each other, so that at the very minimum they are inextricably intertwined. If we do not get our economic interactions right, our social interactions will fail too, and vice versa., In other words, the social and economic fields are game theoretically identical; and they are substantively inseparable, even though they are not identical. Arguably the chief reason that we often separate them is that their modal focuses differ dramatically. In the development of microeconomics the focus is overwhelmingly on pairs involved in exchange. Politics primarily deals with the larger group and social levels of interaction. The movements of rational choice theory and of institutional economics in our time are fairly far reaching efforts to bring these two focuses together.