A
paradigm shift is a phrase that was popularized by American physicist
Thomas Kuhn to describe the nature of scientific revolutions, or fundamental changes in the basic
concepts and
experimental practices of a . Kuhn contrasts these shifts to the activity of
normal science, which he characterized as scientific work done within a prevailing framework (or paradigm). In this context, the word "paradigm" is used in its original meaning, as "
example" (
Greek:
παραδειγμα).