Knowledge and logic in Hans Reichenbach

This study examines Reichenbach's contributions to epistemology, probability theory, and logic from an interdisciplinary perspective. The main objective of the study is to explain Reichenbach's criticisms regarding the claim to certainty in scientific knowledge within the context of induction, causality, and the philosophical consequences of quantum mechanics, and to systematically present the logical and epistemic justifications for his proposal of three-valued logic. The study consists of three main chapters: Reichenbach's epistemological stance and probability-based understanding of knowledge; the critique of classical two-valued logic and the formulation of three-valued logic within the context of logical theory; and the evaluation of the philosophical impacts of quantum mechanics along with his academic contributions in Turkey. Each chapter presents comparative analyses based on primary sources (Reichen-bach's works) and secondary literature. As a methodology, historical-analytical examination, textual analysis, and philosophical argumentation are utilized together; in particular, refe-rences are made to passages in their original language as much as possible to preserve the linguistic nuances of the original texts. Furthermore, Reichenbach's studies at Istanbul Uni-versity between 1930 and 1938 made a significant contribution to the development of mo-dern logic and scientific philosophy in Turkey. Reichenbach's contributions to logic and the philosophy of science through his academic work in Turkey are also addressed within a his-torical context. The limitations of the study are explicitly stated: not all of Reichenbach's logical de-ductions could be comprehensively covered in a single study; certain discussions are conve-yed at a summary level, particularly due to access restrictions to some of the German and English sources. These limitations are discussed in detail in the references and recommenda-tions section for future research. In conclusion, the thesis argues that Reichenbach's proba-bility-centered epistemology and three-valued logic approach played a decisive role in res-haping the logical infrastructure of modern scientific thought. Keywords: Logic, Hans Reichenbach, Logical Empiricism, Three-Valued Logic, Episte-mology, Scientific Philosophy, Probability, Quantum Mechanics.