While Lakatos explores the internal rationality of tradition through its historical reconstruction, he also holds to certain normative standards that would make such a reconstruction unnecessary. If he can stipulate what makes knowledge rational then that it not the part of knowledge which is historical, and vice versa. This difficulty appears in Lakatos’s paraphrase of Kant to the effect that history of science without philosophy of science is blind and philosophy of science without the history of science is empty. The statement suggests a relationship of history and knowledge that raises relativist concerns, concerns that both Lakatos and Popper find disconcerting.