The concept of 'paradigm shift' was introduced by Thomas Kuhn in his seminal work, 'The Structure of Scientific Revolutions'.

Thomas Kuhn, an American physicist and philosopher of science, published 'The Structure of Scientific Revolutions' in 1962, forever altering the discourse on the history and philosophy of science. Prior to Kuhn, the prevailing view was that science progressed incrementally, building upon previous discoveries in a linear fashion. Kuhn argued that scientific progress is instead characterized by long periods of 'normal science' within an established 'paradigm', punctuated by abrupt and revolutionary changes when the old paradigm is overthrown by a new one. Kuhn defined a paradigm as a set of fundamental theories, shared assumptions, and exemplary problems and solutions that guide the research within a scientific community. It's the overarching framework that dictates what counts as legitimate scientific inquiry and what constitutes a valid explanation. This framework is often taken for granted by practitioners, forming the invisible rules of their scientific game.