Discourse on Method is an autobiographical and philosophical work written by Rene Descartes in the early 17th century. It is probably most famous for the quote 'I think, therefore I am'. Descartes addresses the problem of skepticism, and modifies the approach of his predecessors and contemporaries. The work is one of the most important treatises in the development of natural sciences and modern philosophy. It is intended as an introduction to three further works by Descartes: Dioptrique, Meteores, and Geometrie.