Immanuel Kant is one of the most famous philosophers of modern times. Born in 1724 in Königsberg (now Kaliningrad), then the capital of East Prussia, he spent most of his life in his native region, bringing many books to him from and England. The originator of the categorical imperative, this key figure of the German Enlightenment revolutionized Western thought by shedding new light on the notions of reason, tolerance and freedom. To mark the tercentenary of his birth, Wilfried Hauke presents a unique portrait of this emblematic thinker.