The concept of reflection, as developed in a philosophy of consciousness, is in this paper transferred from its sphere of origin, and employed under the label of ‚self-thematization’, as an instrument for social theory. Self-thematization is defined as the construction, with recourse to an environmental context, of a meaningful, reflexive relationship of a system to itself. For this kind of relationship, there can be found, with regard to societal systems, historical illustrations within the traditions of the political and the economic conception of Society. Starting from such examples, connexions may be traced between different types of self- thematization, viz., the autonomous reification of subsystems, the prevailing notions of the world, the level of differentiation attained, and the dominant conviction as to the place of the society on the scale of societal evolution. The main problem confronting today’s world society is that of the contribution the scientific system may make toward societal reflection as a whole.