He had also read almost everything that the contemporary mathematicians Brahe, Kepler and Longomontanus had written and, he told Galileo, he was convinced by the theory of Copernicus that the Earth revolved round the sun. Moreover, he had carefully studied Dialogue Concerning the Two Chief Systems of the World - Ptolemaic and Copernican which Galileo had published about six months before Torricelli wrote his letter.
Niya rin basahin halos lahat na ang mga napapanahong mathematicians Brahe, Kepler at Longomontanus had nakasulat at, siya na sinasabi Galileo, siya ay naniniwala sa teorya ng Copernicus na ang Earth revolved round ng Linggo. Bukod doon, siya ay may-aral ng maingat na pag-uusap tungkol sa Dalawang Chief Systems ng World - mala-Ptolomi at Copernican na Galileo ay nai-publish na ang tungkol sa anim na buwan bago Torricelli wrote kanyang mga sulat.