'''Induction, Traduction, Abduction and Deduction in the Processes of Hypotheses Generation and Justification'''. Y.R. Valkman, O.Y. Dembovskyy '''Abstract'''. ''This paper shortly examines the processes of production and justification of hypotheses in formal and non-formal systems. Different points of view on inductive approach are shown. The levels of hypotheses in complex systems are brought in practice. The properties of inductive inference are defined and studied. Interaction between induction, traduction, abduction and deduction in generation and justification of hypotheses are analyzed. It is shown that for modeling these processes it is necessary to develop the formal methodology, which provides the integration of all classes of inference models. Such a methodology has to support synthesis and analysis of hypotheses by means of continuous interaction of corresponded coherent processes of reasoning. Use of multi-agent approach would be reasonable for development of proper computer technology.'' '''Keywords'''. Logic, induction, traduction, abduction, deduction, modeling, hypothesis, model, investigation '''References'''. [[br]]1. Ðîpper K.R., Conjectures and Refutations: The Growth of Scientific Knowledge. - Routledge, London, 1963. [[br]]2. Blaug M., The Methodology of Economics: Or how Economists Explain.2nd Ed. Cambridge University Press, 1992. [[br]]3. Klir G.J., Architecture of Systems Problem Solving. New York: Plenum Press: 1985. [[br]]4. Finn V.K., "Plausible Reasoning in Intelligent Systems of JSM Type," VINITI. NTI, Ser. 2., No. 15 1991). [[br]]5. Diuk B., Samoylenko A. Data Mining: educational course. Piter Press, 368p., 2001- 368 p. (In Russian) [[br]]6. Peirce C.S. Deduction, Induction, and Hypothesis, Popular Science Monthly, vol. 13, pp. 470-482. - 1878, August, Reprinted (CLL 131-156), (CP 2.619-644), (EP 1, 186-199). Internet Archive CLL. [[br]]7. Valkman Y.R., Bykov V. S. Deductive and non-deductive aspects of imagery thinking modeling// Modeling and informational technologies, The scientific works of IPME, Kiev. 2006, Issue No 35, - pp. 87 - 96. (In Russian) [[br]]8. Valkman Y.R. Intelligent technologies of research design: the formal systems and semiotic models. - Kiev: Port-Royal, 1998. - 250 p. (In Russian).