Any branch of science—microeconomics, nuclear physics, genetics—has at all times, says Kuhn, a single dominant ideological mind-set, something he calls a paradigm. The paradigm is built around a high-level theory about the way the world works, such as Newton’s theory of gravitation or Mendel’s laws of genetics, but it contains much more as well: it identifies, in the light of the theory, what problems are important, which methods are valid ways to go about solving the important problems, and what criteria determine that a solution to a problem is legitimate.
