Karl Wilhelm Feuerbach was a German geometer and the son of legal scholar Paul Johann Anselm Ritter von Feuerbach. After receiving his doctorate at age 22, he became a professor of mathematics at the Gymnasium at Erlangen. In 1822 he wrote a small book on mathematics noted mainly for a theorem at the bottom of one of the pages on the nine-point circle. Shortly before his death he introduced homogeneous coordinates, independently of Möbius. Wikipedia
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