The Great Art; or, The Rules of Algebra

Ars Magna, published in 1545 by Girolamo Cardano, is a foundational work in the history of algebra. It provided the most comprehensive account of solving cubic and quartic equations during the Renaissance. Cardano's approach followed Islamic traditions, presenting specific problem solutions with geometric justifications and using rhetorical descriptions rather than extensive symbolic manipulation.

While Cardano expanded the use of symbols as shorthand, the geometric perspective still dominated, with solutions often represented as line segments. He considered numerous cases for cubic and quartic equations, influenced by his student Ludovico Ferrari's work on the latter. Cardano's work also touched upon the concept of complex numbers, which he found useful but "useless" in practice, a notion later explored more deeply by mathematicians like Rafael Bombelli.123