In this article we argue that a positively formulated theory of education ought to take into consideration empirically based knowledge. Theories of education are normative theories, because they are mainly focused on how the world ought to be: they present ideals, they prescribe preferred repertoires of actions, and they describe valued attitudes. However, using a recent example of an ideal of cosmopolitan education, we here reveal some ways in which prevalent theories of education quickly become remote and powerless if they (...) rebuff empirically based knowledge about peoples’ actual experiences and ways of being in the world. (shrink)