Modern approaches and attempts towards construction of quantum gravity theory and quantum cosmology are reconstructed in terms of Lakatos conception of scientific program and its protective belt. The positive and negative heuristic is investigated in the context of quantum cosmology in Hartle-Hawking and Vilenkin approaches. The author demonstrates that while the program of quantum cosmology is empirically degenerated, it becomes heuristically progressive. He pointed out role of Ambjorn, Loll and Jurkiewicz's hypothesis of quantum dynamical triangulation, which justifies conception of postponed rationality rather than conception of instant rationality. He argues that the field of quantum gravity may be useful for incorporating some new ideas into the conceptions of philosophy of science.