A critical biography of René Descartes, whose first principle (“I think therefore I am.”) reshaped modern philosophy. Often called ‘the father of modern philosophy’, René Descartes’ contributions to philosophy, mathematics and natural science set the intellectual agenda for the seventeenth century. In this biography and assessment of his works, based on the most up-to-date research, Steven Nadler follows Descartes from his early years and education in France to the Dutch Republic, where he lived most of his adult life, to his final months as tutor to Queen Christina of Sweden. Nadler shows how Descartes’ ‘renewal’ of philosophy involved a transformation in both the way in which philosophy is done and the fundamental understanding of the cosmos, the natural world and human nature. His work was a springboard for many of the metaphysical and epistemological problems that continue to engage philosophers today. 'Steven Nadler’s outstanding biography achieves a fine balance of life, ideas and context, allowing Descartes’s philosophy to emerge from its eclectic seventeenth-century milieu in all its dazzling originality and strangeness. Lucid, compelling and unfailingly judicious, this is a marvelous new study of a magisterial modern thinker.' — Clare Carlisle Tresch, King’s College London