This book contains a full statement of the thought of Fichte. Therein lies one of the main strengths and innovations of the text: in just over one hundred pages, written with extreme lucidity and precision, Zöller provides not only an overview of the work of Fichte in its theoretical and practical aspects, but also the frame essential for a thorough reading of the continuous development of the Doctrine of Science. Thus, avoids the usual fragmentary exposure and allows a global approach to characterizing the essential continuity Fichtean thought.