Berkovski, S.2016-02-082016-02-0820110039-7857http://hdl.handle.net/11693/21869I examine Reichenbach's theory of relative a priori and Michael Friedman's interpretation of it. I argue that Reichenbach's view remains at bottom conventionalist and that one issue which separates Reichenbach's account from Kant's apriorism is the problem of mathematical applicability. I then discuss Hermann Weyl's theory of blank forms which in many ways runs parallel to the theory of relative a priori. I argue that it is capable of dealing with the problem of applicability, but with a cost.EnglishConventionFriedmanReichenbachRelative a prioriWeylReichenbach and weyl on apriority and mathematical applicabilityArticle10.1007/s11229-009-9591-z