Article considers methodology of applying the complexity concept in modern scientific discourse. Noting impossibility of its further use in a wellestablished blurred and eclectic form, the author proposes to differentiate this concept for three reasons: syncretic and composite complexity, system complexity and complexity of specialization, complexity of structural elements and inter-elementary links. This differentiation sets a fundamentally new methodological optics in analyzing a wide range of phenomena relating both to the natural sciences and to the humanitarian area, as well as to the problem of evolutionary dynamics.

Article dwells on methodology of complexity concept application in modern scientific discourse. Noting impossibility of its use in a well-settled blurred and eclectic form, the author proposes to differentiate this concept by three arguments: syncretic and combined complexity, complexity of system and complexity of specialization, and finally complexity of structural elements and inter-elementary links. This differentiation sets a fundamentally new methodological optics in analyzing a wide range of phenomena relating to both the natural sciences and humanitarian areas, as well as to the problem of evolutionary dynamics.