"Mises stressed that the important heritage of sound economic thought is not a collection of empirically tested claims about the behavior of economic variables.

"Mises stressed that the important heritage of sound economic thought is not a collection of empirically tested claims about the behavior of economic variables. Rather, economic theory is an internally coherent framework for interpreting "the data" in the first place." Bingo. No doubt the author of the piece would disagree, but he just distilled every failure and problem of "libertarianism" (if not capitalism in general) to a single paragraph. And "interpreting 'the data'" from that school of economic thought has come to mean nothing more than endless rationalization, instead of any reliance whatsoever on empiricism.