52.52, 13.405
Leonard Nelson (; German: [ˈnɛlzɔn]; 11 July 1882 – 29 October 1927), sometimes spelt Leonhard, was a German mathematician, critical philosopher, and socialist. He was part of the neo-Friesian school (named after post-Kantian philosopher Jakob Friedrich Fries) of neo-Kantianism and a friend of the mathematician David Hilbert. He devised the Grelling–Nelson paradox in 1908 and the related idea of autological words with Kurt Grelling.Nelson subsequently became influential in both philosophy and mathematics, as his close contacts with scientists and mathematicians influenced their ideas. Despite dying earlier than many of his friends and assistants, his ISK organization lived on after his death, even after being banned by the Nazi Regime in 1933. It is even claimed that Albert Einstein supported it. He's also credited with popularizing the Socratic method in his book Die sokratische Methode (The Socratic Method).