Compared with another founder of philosophical anthropology Max Scheler, Plessner is desolated by Chinese academe. His works have not been translated into Chinese systematically, and there are few articles about his life and thoughts. The reasons for this are complicated, but the most important point of these is that Plessner has paid most of his attention to the German problems. However, Plessner’s thought, especially his critique of social radicalism, enlightens us a lot. Plessner’s critique of modernity stimulates us to think about the controversy which broke out between New Left-wingers and Liberalists in the late 20th century and to discern the common ground between the two parties: Radicalism.