Kazimierz Twardowski’s contribution to the evolution of logicin Poland
Twardowski’s legacy, which has been published so far—and the detailed analysis of it—suf fices to consider him a classic of Polish semiotics. The published results of Twardowski in the field of methodology also deserve high scores. A new light on the contribution of Twardowski to the development of logic in Poland sheds the content of his unpublished legacy, including the content of his lectures on logic and unedited logical monographs. Firstly, Twardowski conducted fruitful research on many methodological problems. The result of this research was—an unknown to a wider audience—a new approach to the theory of induction and an original sketch of the perspectives of the inductive method in metaphysics, the first in our literature such a comprehensive monograph on reasoning and reconstruction of the concept of understanding. Secondly, Twardowski referred in his unpublished lectures and monographs to the important results of the nineteenth-century formal logic, thus giving their students an important impulse for individual research in this field. In this text, I focus my attention on the logical issues raised by Twardowski just in his unpublished texts.