H. L. A. Hart

Herbert Lionel Adolphus Hart was an English legal philosopher. He was Professor of Jurisprudence at Oxford University and the Principal of Brasenose College, Oxford. His most famous work is The Concept of Law, which has been hailed as "the most important work of legal philosophy written in the twentieth century". He is considered one of the world's foremost legal philosophers in the twentieth century, alongside Hans Kelsen.