postulate

v. (-ting) 1 (often foll. By that) assume as a necessary condition, esp. As a basis for reasoning; take for granted. 2 claim. n. 1 thing postulated. 2 prerequisite or condition.  postulation n. [latin postulo]

n. Something demanded or asserted; especially, a position or supposition assumed without proof, or one which is considered as self-evident; a truth to which assent may be demanded or challenged, without argument or evidence.