Paradigms and paradigm shifts:
Kuhn said that what distinguishes scientific disciplines from non-scientific disciplines is a shared set of assumptions and methods- a paradigm
Kuhn argued that social sciences (including psychology) lack a universally accepted paradigm and are best seen as 'pre-science', unlike natural sciences such as biology
Paradigm shifts occur, according to Kuhn, when there is a scientific revolution. A handful of researchers begin to question the accepted paradigm when there is too much contradictory evidence to ignore