Economics and Sociology

Yes. That is the great transformation of modern popular economics. It is finally recognized that economic activity is inextricably linked to sociology in multiple ways. It is the only reason that economics is successfully being used at all to intervene in the ongoing political fetish for social engineering.

Increasingly, fields are defined by their methodology, not their "themes". Economic imperialism (or for that matter, physical imperialism into biology, computer science, "econophysics") is the outcome because right now, positivism and empirical (quant) studies are "in", at least in the US. If instead the "in" method was postmodernism, we'd see literary imperialism or somesuch as was (briefly?) observed in France.

Once you all tire of writing footnotes to Smith and Ricardo, why not become sociologists? After all, the present incumbents have achieved nothing of note.

This is where 'Rational Man' comes to the rescue. Dah da da dah!