1667-1733

Italian Mathematician

In Euclides ab omni naevo vindicatus (1733), Girolamo Saccheri was the first mathematician to suggest the possibilities of non-Euclidean geometry. He did not follow through with his speculations, however, and thus it would be more than a century before other mathematicians took Saccheri's ideas further.

Saccheri was born on September 5, 1667, in San Remo, Italy, which was then part of lands controlled by Genoa. In 1685, when he was 18 years old, he entered the Jesuit order of priests, and five years later went to Milan, where he studied philosophy and theology at Brera, the Jesuit college. Tomasso Ceva (1648-1737), brother of the more famous Giovanni Ceva (1647?-1734), happened to be a professor of mathematics at Brera, and encouraged the young Saccheri to take up the discipline.

Ordained at Como in 1694, Saccheri went on to teach at a number of Jesuit-sponsored colleges throughout Italy. At...