 Reinforced by the Viennese School Reform movement led by Glöckel, his scientific attitude, and the philosophy of logical empiricism, was the scientific and empirical attitude towards models of education. This applied to the methods and tools of visual education in two ways: by applying accepted recent ideas from empirical disciplines such as developmental psychology, anthropology, art history, even ideas by his Encyclopedia co-editor Charles Morris in his Foundations of a Theory of Signs (Morris 1938); and by testing the end-products, albeit with different degrees of rigor (see the supplementary document on  Visual Education).