Some of the greatest minds in the history of mathematics ask this question, people like Ibn al-Haytham, Omar Khayyam, Nasir al-Din al-Tusi, Giovanni Saccheri, János Bolyai, Carl Gauss, and Nikolai Lobachevsky.
Muitos grandes matemáticos fizeram essa pergunta: pessoas como Ibn al-Haytham, Omar Khayyām, Nasir al-Din al-Tusi, Giovanni Saccheri, János Bolyai, Carl Gauss e Nikolai Lobachevsky.