Å·±¦ÓéÀÖ

“Obviously, not everything can be proved, just as not everything can be defined. If every proposition had to be proved, there would be no beginning to any proof. Such things as axioms and assumptions or postulates are needed for the proof of other propositions. If these other propositons are proved, they can, of course, be used as premises in further proofs. (P. 131)”
― Mortimer J. Adler, Charles Van Doren, How to Read a Book: The Classic Guide to Intelligent Reading