Abstract

This thesis examines the intellectual debate between Thomas Kuhn and Karl Popper, two of the most influential philosophers of science of the 20th century. The discussion begins with an introduction to their contrasting views on the nature of scientific progress. Popper emphasized falsifiability as the key criterion of science. In contrast, Kuhn proposed that science develops through paradigms, with periods of normal science interrupted by revolutionary paradigm shifts. The debate between Popper and Kuhn represents one of the most influential and crucial discussions in the philosophy of science, addressing the perspectives on the nature of scientific inquiry and the mechanisms by which scientific knowledge advances. Popper believed that science moves forward by scientists making guesses (conjectures) about how they are refuted, and new, better ideas are created to replace them. This way, science gets closer to the truth step by step. For Popper, falsifiability is the defining criterion of science, and progress occurs linearly as false theories are discarded and replaced by better ones, bringing us closer to the truth (Popper 2002, 33-34). Kuhn disagreed with Popper's idea of the steady, logical progress in science. He introduced the idea of paradigms, which are shared ways of thinking or frameworks that guide how scientists work. Most of the time, scientists focus on solving puzzles within these paradigms—this is what Kuhn called "normal science." However, when too many problems (or anomalies) arise that the current paradigm can't solve, a crisis happens. This leads to a "scientific revolution," where the old paradigm is replaced by a new one. Kuhn argued that these changes do not necessarily bring science closer to the ultimate truth but instead reflect a shift in how scientists view and approach problems. Science, according to Kuhn, does not progress in a straight line but is shaped by history and social factors (Kuhn 1970, 10-11).

The main points where Popper and Kuhn disagreed include how falsification works, whether science progresses in a straight line or cycles, and whether science is objective or shaped by the prevailing paradigm. Popper focused on the importance of logic and the search for truth, while Kuhn pointed out the influence of social and historical factors on scientific development. Their ideas continue to be important today, offering different views that help us understand both the rational and social aspects of scientific work. This debate highlights that science is complex, involving both reasoning and social influences, and that there are various ways to think about how it progresses. Together, Popper and Kuhn’s ideas give us a deeper understanding of how science works, with its strengths and limitations.