The authors examine the issue of consciousness from a systemic-theoretical perspective, not based on experimental research. They argue that psychological problems are so distant – in intellectual terms – from reality that tracing the relations between observable, experimentally measurable phenomena and internal processes in mind seems to be almost impossible. Moreover, the whole system of information processing in humans – including consciousness – is of multimodal nature, which makes all analyses rather difficult. As a result, it appears impossible to assign unambiguously psychological processes to observable phenomena. Thus, the authors propose to apply a mental technique termed “interpretation of the best explanation” based on the five-level construction of movement theory by N.A. Bernstein (systemic, in fact) and a less detailed motor theory of language by R. Allott. They propose the definition of the term “consciousness” and show its place in the whole chain of events determining human behavior. By using Bernstein’s theory, they define the terms “real consciousness”, “virtual consciousness”, “potential consciousness” and “active consciousness”, coherent with the theory of attention by R.M. Nideffer. They compare the issues under consideration with problems of physics and draw a conclusion that the questions of mechanisms determining animal and human behavior – the only observable manifestation of which is a movement – are probably most challenging to the whole contemporary science