When the celebrated German philosopher Johann Gottlieb Fichte lost his position at the University of Jena and moved to Berlin, it looked as if his career was over. In 1799 Berlin had no university, and Fichte was consigned to lecturing in his home. In Fichte in Berlin Matthew Nini breaks with scholarly consensus, arguing it was there that Fichte finally reached maturity, and the only way to understand Fichte’s mature philosophy is to perform it for oneself. The book focuses on the philosopher’s 1804 lectures on the Wissenschaftslehre – an untranslatable neologism for his theories on the pursuit of insight – claiming that they are one of the most exemplary versions of the philosophical project that Fichte reconfigured some seventeen times throughout his life. While the 1804 lectures offer a more robust approach, they remain faithful to the insight at the heart of the original philosophy. Fichte’s work always emphasized the practical over the theoretical, and his 1804 work goes even further: to think with Fichte is to bring one’s own philosophy to life. Nini guides the reader step by step through the complex arguments Fichte made in 1804 and goes on to examine some of his other works produced in their wake, arguing that Fichte’s output from 1804 to 1806, his first Berlin period, forms an organic whole. Fichte in Berlin is not only an introduction to Fichte’s later philosophy, but also an original philosophical work that makes a unique contribution to the study of German Idealism.