On Paradigm Shifts

The American physicist and philosopher Thomas Kuhn redirects the way we view science from Karl Popper’s never-ending conjecture/refutation cycle to a more subtle process, entwined with cultural and historical context. Kuhn popularized the term “paradigm” as a way to describe universally recognized scientific achievements in conjunction with a set of standards of solution accepted by a scientific community in a field. Each scientific field begins in a state of “pre-paradigm science”, wherein the work is not well organized and relatively ineffective; but eventually, some illuminating piece of work provides insight and depth, sparks inspiration and additional investigation, and further work begins to propagate on its foundation.

Voila! A paradigm has emerged!

To properly comprehend the nuanced concept of the paradigm shift, we must first take a look at the different phases of science according to Kuhn. The first, most common phase Kuhn calls “normal science”, in which scientists go about solving puzzles and resolving anomalies, incrementally making changes to the current paradigm. The second phase involves a pile-up of anomalies, resulting in what Kuhn calls a “crisis”, in which scientists are willing to try anything to resolve the issues that have arisen. Kuhn calls phase three a “revolution”, in which, as a response to the crisis at hand, new solutions and ways of thinking emerge. The final phase is the “paradigm change”, in which a new way of thinking finally usurps the old.

The revolutionary periods in science consist of a breakdown of the established order, followed by a period of rebuilding with the newly established fundamentals. There are numerous historical examples of Kuhnian paradigm shifts, amongst the earliest in the natural sciences being the transition from Ptolemaic geocentrism to Copernican heliocentric cosmology in the sixteenth century. The rejection of one paradigm comes hand-in-hand with the acceptance of another—a more modern example being the transition from Newtonian gravity—a model that stood up to over two centuries of scrutiny—to Einstein’s General Relativity in the twentieth century.

According to Kuhn, reality itself is paradigm-dependent, and after a revolution, scientists work in a completely “different world”. While it appears he intended for this to be interpreted rather literally, I believe it is evident this is at least symbolically quite true.