<p>This paper explores rationality in scientific inquiry from a historical perspective. Rationality in scientific research requires stringent tests of reason and evidence; its use and definition have evolved significantly over time. The paper reviews major philosophical developments from ancient philosophers such as Plato and Aristotle, to medieval scholars like Thomas Aquinas and Zera Yacob, and to modern philosophers. Focusing on the philosophy of science, the paper examines various conceptions of scientific rationality, including Bacon’s inductive approach, Popper’s critical rationalism, relativist views of Kuhn and Lakatos, and the radical critiques of Nietzsche and Feyerabend. This retrospective highlights the dynamic and complex nature of rationality in science and its relevance for management and administrative studies, particularly in decision-making, organizational change, and evidence-based practices.</p>