Jean-Victor Poncelet

Who was Jean-Victor Poncelet?

Jean-Victor Poncelet was a French engineer and mathematician who served most notably as the commandant general of the École polytechnique. He is considered a reviver of projective geometry, and his work Traité des propriétés projectives des figures is considered the first definitive paper on the subject since Gérard Desargues' work on it in the 17th century. He later wrote an introduction to it; Applications d’analyse et de géométrie.

As a mathematician, his most notable work was in projective geometry, in particular, his work on Feuerbach's theorem. He also made discoveries about projective harmonic conjugates; among these were the poles and polar lines associated with conic sections. These discoveries led to the principle of duality, and also aided in the development of complex numbers and projective geometry.

As a military engineer, he served in Napoleon's campaign against the Russian Empire in 1812, in which he was captured and held prisoner until 1814.