Habermas’s discourse ethics is prescribed for the legitimacy crisis in the late capitalist society. Although Habermas emphasizes that his theory has strong practical concerns and it is a kind of theoretical paradigm of “post-metaphysics”, it has been criticized and challenged by many empiricists and empirical researchers. In order to combine the normative theory with political and social practices, the building of middle-range theories to make a dialogue between them is very necessary. Recent empirical studies on this issue can be regarded as an attempt to build middle-range theories so as to dissolve the tensions between theory and practice. Obvious tensions between philosophical studies on discourse ethics and empirical researches on it in social sciences, as well as those between qualitative and quantitative researches, need to be overcome by extending the methodological horizons of different disciplines.