The article shows that in applied problems of multicriteria selection it isn’t necessary any more to formalize criterion mathematically as a function. It can be defined by means of verbal language as the name of significant feature of selection option. It is possible to use criteria, understood as a function, in fundamental research. Moreover, specifics of multicriteria selection as scientific-applied direction is disclosed: it is shown that it is not reduced to optimization theory as such.

The article formulates and discusses in details two fundamental properties of cognitive processes activation methods for solving the IV level complexity problems. Complexity level is determined by some type of cognitive process, which is considered from gnoseological positions.