Natural Sciences
"Paradigm shift" is a term coined by the American physicist Thomas Kuhn to describe the moment when a natural process is discovered which fundamentally undermines established scientific principles. Examples of this would include Einstein's theory of special relativity, which seemed to challenge Newton's universal laws, the Copernican heliocentric model overturning the centuries old geocentric view of the universe. Kuhn did not believe that the concept of a "scientific revolution," or paradigm revolution, could apply to subjects outside of the natural sciences and mathematics.
Economics
The concept of paradigm revolution is difficult to apply to the social sciences as different theories using different principles are viewed as equally valid. In the natural sciences one set of fundamental principles is used to find explanations for certain phenomena. However, very significant theories in economics might be said to have changed the assumptions of those who control or comment on national economies. John Maynard Keynes' work on economic cycles and suggestions on using fiscal and monetary policy to mitigate the effects of recession has been described as a paradigm shift.
Sociology
An entire society or culture can undergo a paradigm shift, perhaps more readily than individual scientists who have built their livelihoods and reputations around certain fundamental principles. Sudden cultural revolution has caused generations of people to view the world, their relationships with government or their collective ambition in a wholly different light. The First World War transformed the view of European peoples from accepting wars as an inevitable part of diplomatic relations to avoiding conflict at all costs.
Colloquial Use
Paradigm revolution has become a concept which has begun to lose some of its original force. It has become a common term in advertising or in business, despite very rarely actually referring to a shift in consciousness or a re-evaluation of founding principles. The term can even be used to describe personal epiphanies, perhaps a religious conversion or re-evaluation of life priorities.