ABSTRACT
This chapter is devoted not so much to one specific concept, as to the specific vision of the state and government that underlay it. Forma mixta meant not just a system of government, but rather the specific construct of the Rzeczpospolita itself, comprising three elements: king, senators and noble “people.” The concept of forma mixta became one of the foundations of the noble political discourse in the second half of the sixteenth century, then serving as a good tool for describing the political reality. Over time, however, great attachment to the concept started to cause problems, becoming an obstacle to aptly describing the changing political reality and hampering the formulation of new concepts. This was not overcome until the eighteenth century, when the concepts of sovereignty and the separation of powers were introduced into discourse.
