How are methodological assumptions defended in philosophy? They can be defended in, say, physics by the accuracy of predictions, confirmation or disconfirmation of theory, or overall productivity of a research program. In philosophy none of these hold water in the same way. If straightforward argumentation is the way to defend them, then how are methodological assumptions different than any other assumptions? I’m thinking of Grice’s Modfied Occam’s Razor that says you should not multiply semantic posits beyond necessity. What sort of thing counts as justification or evidence of that?