Social scientists, particularly political scientists and sociologists, have cited relative deprivation, especially temporal relative deprivation, as a potential cause of social movements and deviance, leading in extreme situations to political violence such as rioting, terrorism, civil wars and other instances of social deviance such as crime. For example, some scholars of social movements explain their rise by citing grievances of people who feel deprived of what they perceive as values to which they are entitled. Similarly, individuals engage in deviant behaviours when their means do not match their goals.