In the present article discusses the features of the transformation of biological knowledge in the context of the emergence of the classical picture of the world. Formation of the classical picture of the world due to the emergence of the classical type of scientific rationality (V.S. Stepin), which led to a particular interest in categorical semantic grid of the new European reality to how formalized the relationship of man with the world, ie the problem of the relation «words» and «things», which was the ordering principle proposed by Michel Foucault in the concept of «episteme». Treatment is carried out not only to the concepts of «scientific revolution» and «paradigm», which are developed postpositivists, but historically changing patterns, «historical a priory» that determine the conditions of existing perspectives, theories and sciences in each historical period, which Michel Foucault designated as «episteme».