[1] Schlesinger attended the high school in Pressburg and later studied physics and mathematics in Heidelberg and Berlin.

He wrote an article on the function theory of Carl Friedrich Gauss and translated René Descartes' La Géométrie into German (1894).

Like his teacher Fuchs, he worked primarily on linear ordinary differential equations.

[6] He also studied differential geometry, and wrote a book of lectures on Albert Einstein's general relativity theory.

[7] Today, his best known work is Über eine Klasse von Differentialsystemen beliebiger Ordnung mit festen kritischen Punkten (Crelle's Journal, 1912).