The present state of the problem of determinism and causality in quantum mechanics and various points of view on the nature of microparticles are discussed. A classification of microparticles by sizes of their region of existence is carried out. The analogy is considered between the disintegration and stability of a neutron, on the one hand, and radioactive and stable nuclei, on the other hand. The idea on possibility of radioactive nuclei stabilization for solving the problems of disposal of radioactive wastes and elimination of consequences of nuclear disasters is stated.