This dissertation treats of the problem of attributing the occurrence of an individual event or state to a single cause — a problem commonly understood either as a question of distinguishing the cause from the mere conditions or as a matter of singling out, from several causes, one cause, as the cause. The main purpose of the study is to clarify some basic concepts, and some criteria of ascertainment of the cause, that may be discerned in the literature on causal attribution. Special attention is devoted to how the adequacy of causal attributions depends on pragmatic factors. The study begins with an analysis of J. S. Mill’s distinction in A System of Logic between a scientific and a common-parlance approach to the problem of causal attribution. Mill’s assumption that causal attribution in science always requires a universal-law subsumption is then examined in the context of a general discussion of the range of applicability of the covering-law model of explanation. Mill’s scientific and common-parlance notions of cause are compared with R. G. Collingwood’s historical (sense-I) and scientific (sense-II and -III) notions of cause. It is argued that there are purposes of inquiry for which Mill’s common-parlance approach is more relevant to causal attribution in natural science than his scientific approach. And, more generally, it is argued that although law subsumptions are necessary for the ascertainment of the causes, more is often required for explaining the effect. Samuel Gorovitz’s differentiating-factor analysis is discussed, and limitations of the model are identified. The relevance of Morton White’s abnormalistic approach to historical research is also examined. Further, a number of objectivistic approaches are discussed, and it is argued that objectivity is not attainable in causal attributions in a sense in which it always implies an improvement of our ability to attribute the occurrence of an individual event or state to a single cause.