Non-Euclidean geometry that are both perpendicular to a third line: Euclidean geometry, named after the Greek mathematician Euclid, includes some of the oldest known mathematics, and geometries that deviated from this were not widely accepted as legitimate until the 19th century. The debate that eventually led to the discovery of the non-Euclidean geometries began almost as soon as Euclid's work "Elements" was written. In the "Elements", Euclid began with a limited number of assumptions (23 definitions, five common notions, and five postulates) and sought to prove all the other results (propositions) in the work. The most notorious of the postulates is often
Ptolemy II of Telmessos Telmessos, as he ruled from 206 BC to until at least 181 BC. According to surviving inscriptions at Telmessos, Ptolemy II didn’t seem to have a royal title nor it is clear his relationship with the Pharaohs in Alexandria. It seems likely that his family had relative autonomy from Ptolemaic control increased. As Ptolemaic power declined rapidly and dramatically outside of Egypt after the death of Ptolemy III Euergetes in 222 BC, probably Ptolemy II’s father with his family had the motive and opportunity for divorcing themselves from Ptolemaic suzerainty. At an unknown date during his father’s reign, Lysimachus with