Editing Falsifiability (section)

===Normal science versus revolutionary science===

{{main|Paradigm shift}}
[[Thomas Kuhn]] analyzed what he calls periods of normal science as well as revolutions from one period of normal science to another,{{sfn|Kuhn|1996}} whereas Popper's view is that only revolutions are relevant.<ref name="kuhnonpoppersviewonrevolution" group="upper-alpha"/><ref name="watkinsonPopperVsKuhn" group="upper-alpha"/> For Popper, the role of science, mathematics and metaphysics, actually the role of any knowledge, is to solve puzzles.<ref name="knowledgebeginswithproblems" group="upper-alpha"/> In the same line of thought, Kuhn observes that in periods of normal science the scientific theories, which represent some paradigm, are used to routinely solve puzzles and the validity of the paradigm is hardly in question. It is only when important new puzzles emerge that cannot be solved by accepted theories that a revolution might occur. This can be seen as a viewpoint on the distinction made by Popper between the informal and formal process in science (see section {{slink||Naive falsificationism}}). In the big picture presented by Kuhn, the routinely solved puzzles are corroborations. Falsifications or otherwise unexplained observations are unsolved puzzles. All of these are used in the informal process that generates a new kind of theory. Kuhn says that Popper emphasizes formal or logical falsifications and fails to explain how the social and informal process works.