the writing of this kind of philosophical history can never be brought to completion. The possibility has always to be left open that in any particular field, whether the natural sciences or morality-and-moral-philosophy, or the theory of theory, some new challenge to the established best theory so far will appear and will displace it. Hence this kind of historicism, unlike Hegel’s, involves a form of fallibilism; it is a kind of historicism which excludes all claims to absolute knowledge.
