one is as reliable as the other just in case it succeeds in all the worlds the other one succeeds in. That's all there is to it! (Kelly et al. 1997) On the proper role of methodology: "It is for empirical science to investigate the details of the mechanisms whereby we track, and for methodologists to devise and refine even better (inferential) mechanisms and methods" (Nozick, 1981) See also Algorithmic learning theory Bayesian confirmation theory Belief revision Computational learning theory Epistemology Formal epistemology Inductive reasoning Language identification in the limit Machine learning Methodology Philosophy of science Problem of induction Scientific method References Blum, M. and Blum, L. (1975). "Toward a Mathematical Theory of Inductive Inference", Information and Control, 28. Feldman, Richard, Naturalized Epistemology, The Stanford Encyclopedia of Philosophy (Fall 2001 Edition), Edward N. Zalta (ed.). Glymour, C. and Kelly, K. (1992). ‘Thoroughly Modern Meno’, in: Inference, Explanation and Other Frustrations, ed. John Earman, University of California Press. Gold, E. M. (1965) "Limiting Recursion", Journal of Symbolic Logic 30: 27-48. Hájek, Alan, Interpretations of Probability, The Stanford Encyclopedia of Philosophy (Summer 2003 Edition), Edward N. Zalta (ed.). Harrell, M. (2000). Chaos and Reliable Knowledge, Ph.D. Thesis, University of California at San Diego. Harrell, M. and Glymour, C. (2002). "Confirmation And Chaos," Philosophy of Science, volume 69 (2002), pages 256–265 Hawthorne, James, Inductive Logic, The Stanford Encyclopedia of Philosophy (Winter 2005 Edition), Edward N. Zalta (ed.). Hendricks, Vincent F. (2001). The Convergence of Scientific Knowledge, Dordrecht: Springer. Hendricks, Vincent F. (2006). Mainstream and Formal Epistemology, New York: Cambridge University Press. Hendricks, Vincent F., John Symons Epistemic Logic, The Stanford Encyclopedia of Philosophy (Spring 2006 Edition), Edward N. Zalta (ed.). Hodges, Wilfrid, Logic and Games, The Stanford Encyclopedia of Philosophy (Winter 2004 Edition), Edward N. Zalta (ed.). Kelly, Kevin (1996). The Logic of Reliable Inquiry, Oxford: Oxford University Press. Kelly, Kevin (2000a). ‘The Logic of Success’, British Journal for the Philosophy of Science 51:4, 639-660. Kelly, Kevin (2000b). "Naturalism Logicized", in After Popper, Kuhn and Feyerabend: Current Issues in Scientific Method, R. Nola and H. Sankey, eds, 34 Dordrecht: Kluwer, 2000, pp. 177–210. Kelly, Kevin (2002). "Efficient Convergence Implies Ockham's Razor", Proceedings of the 2002 International Workshop on Computational Models of Scientific Reasoning and Applications, Las Vegas, USA, June 24–27, 2002. Kelly, Kevin (2004a). "Uncomputability: The Problem of Induction Internalized", Theoretical Computer Science, pp. 317: 2004, 227-249. Kelly, Kevin (2004b). "Learning Theory and