The edition presents a hitherto unknown manuscript of Gotthold Ephraim Lessing: a notebook with the working titel ›On the similarity between the Greek and the German language . Beginning on 1st December 1759, Lessing makes entries on etymological and historical-linguistic observations and underlines in this way how significant philological and historical linguistic questions were to him. The collection sheds light on the scholarly foundation of Lessing's writing and thought, and reveals the process by which he arrives at his often revolutionary standpoints. The edition provides a commentary and a comprehensive afterword that also gives an introduction to the contemporary scholarly contexts.