Rene Descartes wrote a philosophical and autobiographical work titled Discourse on the Method of Rightly Conducting One's Reason and of Seeking Truth in the Sciences, which was published in 1637. The most well-known use of it is as the inspiration for the idiom "Je pense, donc Je Suis," which appears in Part IV of the work. Meditations on First Philosophy (1641) contains a similar argument but without this same language, and Principles of Philosophy contains a Latin translation of the identical claim, Cogito, ergo sum (1644). One of the most influential books in the history of contemporary philosophy, Discourse on the Method is crucial to the advancement of the natural sciences. Descartes addresses the issue of skepticism in this work, which was previously researched by other philosophers. Descartes adapted the methods of some of his predecessors and contemporaries while addressing a fact that he believed to be indisputable; in order to observe the world honestly and without any bias, he started out on his line of reasoning by doubting everything. The book's initial printing took place in Leiden, Netherlands. Dioptrique, Meteores, and Geometrie were the three works that the book was meant to provide as an introduction.