Gerolamo Cardano

Gerolamo Cardano was an Italian <a href="/facts/Polymath/eqIfjQRu">polymath</a> whose interests and proficiencies ranged through those of mathematician, <a href="/facts/Physician/qJ3woFvG">physician</a>, <a href="/facts/Biologist/yJJGXyKR">biologist</a>, <a href="/facts/Physicist/cQcgvSIm">physicist</a>, <a href="/facts/Chemist/N09K7Bdm">chemist</a>, <a href="/facts/Astrologer/kFP09KjH">astrologer</a>, <a href="/facts/Astronomer/ronF8j4a">astronomer</a>, <a href="/facts/Philosopher/Hyvzc54m">philosopher</a>, <a href="/facts/Music_theorist/BoekvflP">music theorist</a>, <a href="/facts/Writer/3xKMB3yB">writer</a>, and <a href="/facts/Gambler/Hgw4a9DH">gambler</a>. He became one of the most influential mathematicians of the <a href="/facts/Renaissance/4D9Bc6KU">Renaissance</a> and one of the key figures in the foundation of <a href="/facts/Probability/fgYvMhwb">probability</a>; he introduced the <a href="/facts/Binomial_coefficients/Tsx7eY5h">binomial coefficients</a> and the <a href="/facts/Binomial_theorem/hd4SmkUd">binomial theorem</a> in the Western world. He wrote more than 200 works on science.
Cardano partially invented and described several mechanical devices including the <a href="/facts/Combination_lock/Xy6zqVFT">combination lock</a>, the <a href="/facts/Gimbal/FI8hEuss">gimbal</a> consisting of three concentric rings allowing a supported <a href="/facts/Compass/86MaeFXu">compass</a> or <a href="/facts/Gyroscope/UjXGsfMq">gyroscope</a> to rotate freely, and the <a href="/facts/Cardan_shaft/lHnhqzzT">Cardan shaft</a> with <a href="/facts/Universal_joint/UkDnAv2q">universal joints</a>, which allows the transmission of rotary motion at various angles and is used in vehicles to this day. He made significant contributions to <a href="/facts/Hypocycloid/XH6rx5I0">hypocycloids</a> - published in De proportionibus, in 1570. The generating circles of these hypocycloids, later named "Cardano circles" or "cardanic circles", were used for the construction of the first high-speed <a href="/facts/Printing_press/7I3laFE0">printing presses</a>.
Today, Cardano is well known for his achievements in <a href="/facts/Algebra/nMdqczjo">algebra</a>. In his 1545 book <a href="/facts/Ars_Magna_(Cardano_book)/aVVFlLkQ">Ars Magna</a> he made the first systematic use of <a href="/facts/Negative_numbers/LzErzCmI">negative numbers</a> in Europe, published (with attribution) the solutions of other mathematicians for <a href="/facts/Cubic_equation/Eqm3HCMx">cubic</a> and <a href="/facts/Quartic_equation/SjjtXkHL">quartic equations</a>, and acknowledged the existence of <a href="/facts/Imaginary_number/6Xh9W3hq">imaginary numbers</a>.

Gerolamo Cardano open-in-new

Gerolamo Cardano