The paper gives an explication of the key ideas and discoveries of the prominent scholar, Nobel Prize winner Ilya Prigogine (1917-2003) which opened new methodological perspectives not only for natural sciences but also for social and human sciences. The focus of the paper is the relevance of these ideas for the psychology of our days.The development of the concept of bifurcation in irreversible systems suggests the awareness of limitations of the determinism principle and to the impossibility of prediction of the dynamics of complex systems, to the understanding of natural laws as referring to the possible rather than to the necessary, and to the scientific justification of personal causality as well as freedom and responsibility as two its aspects. The development of the ideas on the role of fluctuations in the dynamics of irreversible systems suggests the revision of the role of individual agency in the dynamics of macrosocial systems. Prigogine's ideas are extremely important for the understanding of the perspectives of transformation of psychological science in the 21st century from the study of predictability and self-consistency of individuals to the understanding of personality as self-determined and self-organized system that creates a higher order out of uncertainty and chaos.