With the emergence of the national social movement in the eighteenth century, early theorists focused on the three facets of movements that they feared the most: extremism, deprivation, and violence. Both the French Revolution and early nineteenth-century industrialism lent strength to this reaction. Led by sociologist Emile Durkheim (1951), nineteenth-century scholars saw social movements as the result of anomie and social disorganization – an image well captured in the phrase “the madding crowd” (see the review in McPhail 1991).

… But these characteristics are polar cases of more fundamental characteristics of social movements. Extremism is an exaggerated form of the frames of meaning that are found in all social movements; deprivation is a particular source of the common purposes that all movements express; and violence is an exacerbation of collective challenges. Rather than seeing social movements as expressions of extremism, violence, and deprivation, they are better defined as collective challenges, based on common purposes and social solidarities, in sustained interaction with elites, opponents, and authorities.

— Sidney Tarrow, Power in movement: Social movements and contentious politics (2nd Ed.) (1998), pp. 4-5