German philosopher widely acknowledged to be one of the most original thinkers of the 20th century, he was also one of the most important representatives of the phenomenological movement. His best known book is Being and Time (Sein und Zeit), published in 1927. Heidegger succeeded Husserl as professor for philosophy at the University of Freiburg, where he was later also elected rector. He joined the National Socialist German Workers' (Nazi) Party in 1933.