Relativism can be specified in many ways, into different relativist theses. This chapter explains that first argument is that relativism is in some sense self-refuting, and begins by presenting Plato's version of the argument. By taking account of Pyrrhonism, the relativist can strengthen her case and find arguments for her suggestion. Maria Baghramian fails to notice the distinctive non-doctrinal character of Sextuss scepticism, however, and consequently also fails to see how the relativist can escape certain criticisms by learning from Pyrrhonism. The second standard argument against relativism is only hinted at by Plato, when he writes that in matters of health and disease, it is obvious, also to the relativist, that some persons excel the rest of the people in knowledge. Referring to the scientific attitude is hence not a tenable counter-argument against relativism. The problem with relativism is thus not a matter of whether people understand reasoning criterially or non-criterially, for the practical problem can appear nonetheless.