G. Adlers acquaintance and friendship with philosophers such as A. Meinong, C. von Ehrenfels - the founder of the theory of Gestalt qualities —, and E. Mach, and Adler's general interest in philosophy were conducive to his familiarity to the contemporary discussion about empiricism and the challenge of the humanities by science. Therefore, the search for empirical substantiation of speculative ideas caused great influence on Adler's concept of music history research. Though Adler shared this basic concern with the representatives of comparative musicology his academic career did not bring forth a prolific co-operation with his colleagues at the University of Vienna, R. Wallaschek and R. Lach.