Two logically opposed interpretations of the meaning of current (soft and critical) systems thinking are drawn: thinking about the holistic power structure that constitutes the ground for the possibility of a situation and thinking how to accommodate conflicting parties into a given order. The epochal coexistence of these two apparently logically opposed modes of thinking are interpreted under a historical–ontological perspective. It is shown how the failure of the project of the Enlightenment has led to the constitution of a postmodern order dominated by instrumental thinking and absolute relativism, under the shadow of a few key notions of the project of the Enlightenment that rapidly become "plastic' words in-forming the mass media publicity game. © 1997 John Wiley & Sons, Ltd.