KnowraParallel postulateLinked fromLinked fromThe 22 pages that link to Parallel postulate, each with the reason it gives.All 22Broader topic 3Related 16Compared with 3Euclidean geometryBroader topic: This distinctive postulate separates Euclidean geometry from non-Euclidean geometries.Euclid's ElementsBroader topic: It is the treatise's most distinctive assumption and underlies many results about parallel lines.History of geometryBroader topic: Attempts to prove it from other assumptions eventually helped open geometry beyond Euclid.