Johann Gottlieb Fichte was a German philosopher who lived from 1762 to 1814 and became a founding figure of German idealism. He developed a philosophical system called the Wissenschaftslehre (Doctrine of Scientific Knowledge), which aimed to build upon Kant's critical philosophy by grounding all knowledge in the concept of the "pure I" or self-consciousness. Fichte is also known for his influential works on ethics, political philosophy, and his patriotic "Addresses to the German Nation".