This study is the first to examine in detail the cultural significance of Goethe's scientific work. It explores the subtle distinctions he made between the Amateur and the Expert, and the interplay between Enlightenment science and Romanticism's 'Nature-Philosophy', and attempts to set Goethe's thinking into the context he consistently evoked, of the preceding three millennia of scientific thought. Analysing his complex perception of the cultural centrality of aesthetics, worked out in collaboration with his friend and fellow writer Schiller, the study concludes that Goethe's modes of thought differed from both the Enlightenment and the Romantic traditions, prefiguring the process-thinkers of the twentieth century.