We will review the emergence of philosophy of science in the early twentieth century as a subdiscipline of Western philosophy. We will examine how it has reformulated basic questions and debates in Western philosophy, and how it has addressed them using the means at its disposal. We will review two turns that have occurred in philosophy of science since its emergence as a subdiscipline – the socio-historical turn, and the semantic turn. The course will focus on philosophical questions that are of special interest to historians of science and STS scholars, such as: Is there scientific rationality, and how is it to be conceptualized? What does it mean that science is a social enterprise? As time progresses, does science approximate the truth, at least in some cases? What are ways in which science represents the world? What are the mutual relations between scientific practice and theory? The course readings will mostly consist of classical and contemporary sources that graduate research students today are expected to know; we will also read some cutting-edge sources from current debates in philosophy of science.