Aufbau): Wilhelm Ostwald, a Nobel-prize-winning chemist and leader of the Deutscher Monistenbund (as sucessor of its founder Ernst Haeckel). I will focus on three episodes: (a) Carnap's youth (before the First World War), (b) a meeting in Buchenbach in August 1920, which Carnap organized with some of his Jena friends, and (c) the Aufbau.I am very grateful to André Carus both for transforming my clumsy English text into something readable and for suggesting many valuable additions and clarifications." /> Carnap's early conception of a "system of the sciences" - Dahms Hans-Joachim | sdvig press