The Italian mathematician, astronomer, and physician Geronimo Cardano (1501-1576) initiated the general theory of cubic and quartic equations. He emphasized the need for both negative and complex numbers.

Geronimo Cardano was born in Pavia on Sept. 24, 1501, the illegitimate son of a local jurist, Fazio Cardano. In spite of a boyhood filled with sickness and extreme poverty, he managed to attend the universities of Pavia and Padua, receiving his medical degree from the later in 1524. In 1532 he was appointed to the chair of mathematics in Milan but continued to practice medicine, albeit without much success. In 1536 he gained some notoriety by attacking the then-existing practices of medicine, but this aided rather than hindered him, for 3 years later he was admitted to the College of Physicians and later was appointed rector of the college. In 1543 he was professor of medicine at the University of Pavia.

Mathematical and Other Writings

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