The article shows that the possibilities of interaction of natural and social sciences and humanities should be considered with regard to their specificity. In the natural sciences the principles of proof and refutation coexist separately excluding each other, in social and humanitarian sciences they are inseparable and presuppose each other. Humanities and social sciences bear the contradiction between subjectivity and striving for objectivity; the struggle between scientific schools and the desire to develop a single glance; between the need for evidence based knowledge and limited source (including empirical) basis.