The article discusses Austrian art historian Otto Pächt's manuscript "Logik und Erkenntnistheorie" which adopted the homonymous lectures by German physicist and philosopher Morittz Schlick. Topics discussed include the development of art history as a science, Pächt's summary of the approaches of Schlick to define the concept of knowledge and the general theory of knowledge, and Pächt's development of a theory of image as a theory of representation.