Durkheim's work revolved around the study of social facts, a term he coined to describe phenomena that have an existence in and of themselves, are not bound to the actions of individuals, but have a coercive influence upon them. Durkheim argued that social facts have, "sui generis", an independent existence greater and more objective than the actions of the individuals that compose society. Only such social facts can explain the observed social phenomena. Being exterior to the individual person, social facts may thus also exercise coercive power on the various people composing society, as it can sometimes be observed in the case of formal laws and regulations, but also in situations implying the presence of informal rules, such as religious rituals or family norms. Unlike the facts studied in natural sciences, a "social" fact thus refers to a specific category of phenomena: "the determining cause of a social fact must be sought among the antecedent social facts and not among the states of the individual consciousness."