This article contains philosophical justification of modern economic theory as well as contemplations on the two possible solutions to the problem of microeconomics justification. The first case describes positivism as microeconomics justification, and the second – phenomenological justification of Austrian political economy. The perspectives of subjective method are given. The main feature of this method is that all the notions in economic theory and in activity theory are received in a deductive way from activity axiom. The very axiom is based on the phenomenological reduction.