The demarcation problem, which seeks to delineate the boundaries between science and non-science, was purportedly resolved by Karl Popper’s principle of falsification. Eschewing the logical pitfalls of inductivist verification, Popper proposed that a theory’s scientific status rests not on its capacity to be proven true, but on its inherent refutability. This elegant asymmetry suggested that science progresses through a rigorous process of conjecture and refutation, with theories gaining corroboration by surviving attempts to falsify them. However, this rationalist depiction of scientific advancement was profoundly challenged by Thomas Kuhn’s historical analysis. Kuhn posited that mature sciences operate within a dominant “paradigm”—a constellation of theories, methodologies, and metaphysical assumptions that guide an entire research tradition. During periods of “normal science,” practitioners engage not in falsification of the paradigm itself, but in a puzzle-solving activity, extending its reach and resolving minor anomalies. The accumulation of significant, intractable anomalies may precipitate a crisis, leading not to simple refutation, but to a revolutionary paradigm shift. Crucially, Kuhn introduced the concept of incommensurability, asserting that successive paradigms are often logically irreconcilable. Proponents of competing paradigms effectively inhabit different conceptual worlds, employing distinct terminologies and adhering to divergent standards of evidence. This entails that the transition between them is not governed by a purely logical calculus of refutation but resembles a "gestalt switch," a conversion experience underpinned by a complex interplay of empirical and non-empirical factors. Consequently, the Kuhnian model subverts the Popperian ideal of a linear, cumulative scientific enterprise, recasting progress as a discontinuous process shaped by profound socio-historical contingency. This framework complicates any straightforward, algorithmic definition of scientific rationality.