Jakob Hermann (16 July 1678 – 11 July 1733) was a mathematician who worked on problems in classical mechanics. He is the author of Phoronomia, an early treatise on Mechanics in Latin, which has been translated by Ian Bruce in 2015-16. In 1729, he proclaimed that it was as easy to graph a locus on the polar coordinate system as it was to graph it on the Cartesian coordinate system. He appears to have been the first to show that the Laplace–Runge–Lenz vector is a constant of motion for particles acted upon by an inverse-square central force. Hermann was a second cousin of Leonhard Euler's mother.