The publisher, publicist, literary critic and satirist Friedrich Nicolai is one of the key figures of the German Enlightenment. As an opponent of all irrationalism, he promoted the lively culture of debate among an enlightened public. This volume undertakes a fundamental contextualization of Nicolai in order to adequately measure his achievements as well as his limits. The decisive factor is the critical element, as 'criticism' for Nicolai does not only mean criticism of literature or superstition, but also that fundamental cultural technique of the Enlightenment, which is based on the rationally based differentiation, systematization and assessment of contingent empirical reality. Correspondingly, in the interdisciplinary contributions, so far little noticed, yet central aspects of Nicolai's work emerge in high contrast, such as the moral didax, the popular enlightenment or the encyclopedia, his criticism of religion and his aesthetics of fine art and music.