Abstract
In a priori knowledge we find out not only subject - predicate relationship, but we also discover the necessity of the predication and this is one of the most significant differences between a priori and a posteriori knowledge Kant has taken metaphysical, physical and mathematical propositions as a priori, basically due to the necessity they involve and as to the source of discovering necessity, he presented intuition. This paper deals with different interpretations of a priori knowledge at first, then advances Kripke’s criticisms concerning the concomitance between necessity and apriori knowledge. Then in continue lays stress on this point that as a priori knowledge cannot resort to the experience, likewise it cannot violate a priori knowledge.