Habermas ,in universal pragmatics that he has founded ,set the speech validity in the living wand and extended the validity of factual propositions or forms into the formal social field. Thereby ,the common speech validity has been developed into a kind of universal validity with many sorts of demands and meanings. Sowing the question of universal validity in the living world are perceived. Hence ,Habermas not only verified the universality of communicative rationality ,but also established a brand一new measurement and research framework for natural science and human science.
From Factual World to Normal World( p.19)