The paper addresses one of most important topics in contemporary epistemology, i.e. the controversy between realistic vs. constructivist approach to reality and science. In my article I focus on two representatives of these approaches, on Ian Hacking's realistic view of knowledge, and on Bruno Latour's radical constructivism. In the first part, Latour's idea of anthropological research of the method of sciences is discussed. I argue that Latour's conception boils down to an assertion against there being an universal method of science. In second part I discuss realistic standpoint of Ian Hacking and his view that not all scientific facts are theoretical constructions.