Classical Darwinism explains the mechanism of the origin of qualitatively new kinds, it does not, however, consider progressive evolution as an inevitable process. In order to be able to proceed from many-dimensionality of evolutionary orientation to forming of presuppositions of the origin of a qualitatively new system, we must begin to investigate the biological system, in opposition to classical approach, from the level at which differentiation of biological kinds appears as differentiation of the homogenous. Through the differentiation of plant and animal kinds biological environment grows more complicated and therefore the adaptation to these complex conditions can be secured by adequately more complicated ordered structure of organisms. And so differentiation instead of being continuous quantitative succession of biological quality is the interruption of this succession — a leap from quantitative change into a qualitative one. Contradiction of differentiation and integration which represents the source of this change does not rest only at the level of the whole of organism, as has been conceived hitherto. Integration of differentiated parts of organism, and so progressing autonomization and universalization of animal kinds has its opposite pole outside organism, in differentiation of outward environment.