It is argued that the Achilles heel of contemporary sociology – and great parts of social science – is a) weak theory development, and b) absence of a meta-theory providing a common platform and a shared goal for its practitioners, fostering cumulativity. A meta-theory called causal realism (a variant of critical realism) is suggested for these purposes. The main tenets and key concepts of realism, such as causality and explanation, mechanism, stratified reality, are presented. Thereafter, via an analogy to the physical sciences, it is argued that a natural implication of realism and the search for causal mechanisms is a division of society into levels. The micro-macro issue is approached by a level-ontology for the development of sociological theory. Five levels are suggested, discussed and briefly exemplified. In the concluding remarks, some further positive implications of realism to sociology are touched upon
