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Moderate Realism and Deduction from Truthlike Theories


Moderate realists hold that scientific theories are truthlike, rather than exactly true. Although scientific realism has been challenged by arguments such as the pessimistic induction, moderate realism hasn’t been challenged directly on the grounds that it makes scientific progress rely on inferences from theories that are only truthlike. This paper shows that moderate realism is incompatible with the claim that deductive arguments from scientific theories are reliable. Using truthlike claims as the premises of some patterns of deductive reasoning renders the argument dramatically unreliable. The conclusion is not guaranteed to be true. Nor is the conclusion guaranteed to be at least as truthlike as the premises. Nor even is the conclusion shown to be likely to be true. This is because the consequences of truthlike theories are neither guaranteed to be true, nor even more likely to be truthlike than not. Truthlike theories cannot function like true theories in deductive arguments; instead they function as radically false theories would. In short, truthlike theories behave exactly like radically false theories for the purposes of their deductive consequences. And since scientists would not trust deductions from radically false theories, they should not trust deductions from truthlike theories either. Furthermore, this applies to a wide range of logics and patterns of deductive argument. The moderate realist must either reject bivalence, deny that theories are truth-apt, or accept that scientific theories are not used in deductive arguments.

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  1. A quick clarification on the notion of a deductive form of inference: the eliminative inference type of deductive inference isn’t a form of logic in the usual sense. Granted, it is formal in that it uses forms of which individual arguments are instances. However, is not a form of a logic in the sense that it does not elucidate a logic by specifying a pattern of argument whose instances are valid, so much as assume a logic in its requirement that the eliminators contradict rival theories in the universe. In short, this type of eliminative inference presupposes a logic, and so isn’t a form of a logic in the usual sense. That’s why eliminative inferences are not disjunctive syllogisms. The premises of disjunctive syllogisms set out a universe of rival theories, then directly assert the falsehood of all but one of these rival theories. Eliminative inference mentions eliminators that contradict the rival theories, whilst disjunctive syllogisms only mention that the rivals are false. Eliminative inferences, but not deductive syllogisms, presuppose a notion of logical consequence that goes beyond the rule of non-contradiction.


  • Beall, J. C., & Restall, G. (2000). Logical pluralism. Australasian Journal of Philosophy, 78(4), 475–493.

    Article  Google Scholar 

  • Beall, J. C., & Restall, G. (2006). Logical pluralism. Oxford University Press.

    Google Scholar 

  • Bird, A. (2005). Abductive knowledge and Holmesian inference. Oxford Studies in Epistemology, 1, 1–31.

    Google Scholar 

  • Bird, A. (2010). Eliminative abduction: Examples from medicine. Studies in History and Philosophy of Science Part A, 41(4), 345–352.

    Article  Google Scholar 

  • Chakravartty, A. (2001). The semantic or model-theoretic view of theories and scientific realism. Synthese, 127(3), 325–345.

    Article  Google Scholar 

  • da Costa, N. C., Newton, C., da Costa, N. C., & French, S. (2003). Science and partial truth: A unitary approach to models and scientific reasoning. Oxford University Press on Demand.

    Book  Google Scholar 

  • Herschel, J. (1831) Preliminary discourse on the study of natural philosophy. Brown, Green & Longmans, London.

  • Kitcher, P. (1995). The advancement of science: Science without legend, objectivity without illusions. Oxford University Press on Demand.

    Book  Google Scholar 

  • Kuipers, T. A. (2013). From instrumentalism to constructive realism: On some relations between confirmation, empirical progress, and truth approximation 287. Springer Science & Business Media

  • Laudan, L. (1981). A confutation of convergent realism. Philosophy of Science, 48(1), 19–49.

    Article  Google Scholar 

  • Lipton, P. (1993). Is the best good enough?. In: Proceedings of the Aristotelian Society. Aristotelian Society, Wiley 93, pp. 89–104

  • Mackie, J. L. (1980). The cement of the universe. Oxford University Press, Oxford.

    Book  Google Scholar 

  • Massimi, M. (2004). What demonstrative induction can do against the threat of underdetermination: Bohr, Heisenberg, and Pauli on spectroscopic anomalies (1921–24). Synthese, 140(3), 243–277.

    Article  Google Scholar 

  • Miller, D. (1975). The accuracy of predictions. Synthese, 159–191.

  • Miller, D. (1974). Popper’s qualitative theory of verisimilitude. The British Journal for the Philosophy of Science, 25(2), 166–177.

    Article  Google Scholar 

  • Miller, D. (2006). Out of error: further essays on critical rationalism. Ashgate Publishing.

    Google Scholar 

  • Miller, D. (2017). Out of error: Further essays on critical rationalism. Routledge.

  • Niiniluoto, I. (1982). What shall we do with verisimilitude? Philosophy of Science, 49(2), 181–197.

    Article  Google Scholar 

  • Niiniluoto, I. (1987). Truthlikeness. Springer.

    Book  Google Scholar 

  • Niiniluoto, I. (1998). Verisimilitude: The third period. The British Journal for the Philosophy of Science, 49(1), 1–29.

    Article  Google Scholar 

  • Norton, J. D. (1994). Science and certainty. Synthese, 3-22.

  • Norton, J. D. (1995). Eliminative induction as a method of discovery: How Einstein discovered general relativity. In The creation of ideas in physics (pp. 29–69). Springer, Dordrecht, UK

  • Oddie, G. (1986). Likeness to Truth. (Western Ontario Series in Philosophy of Science), Dordrecht: Reidel

  • Popper, K. R. (1963). Conjectures and refutations. Routledge and Kegan Paul.

    Google Scholar 

  • Tichý, P. (1974). On Popper's definitions of verisimilitude. The British Journal for the Philosophy of Science, 25(2), 155–160.

    Article  Google Scholar 

  • Weinert, F. (2000). The construction of atom models: Eliminative inductivism and its relation to falsificationism. Foundations of Science, 5(4), 491–531.

    Article  Google Scholar 

  • Weston, T. (1992). Approximate truth and scientific realism. Philosophy of Science, 59(1), 53–74.

    Article  Google Scholar 

  • Whipple, K. X., DiBiase, R. A., Ouimet, W. B., & Forte, A. M. (2017). Preservation or piracy: Diagnosing low-relief, high-elevation surface formation mechanisms. Geology, 45(1), 91–94.

    Article  Google Scholar 

  • Worrall, J. (2000). The scope, limits, and distinctiveness of the method of’ deduction from the phenomena’: Some lessons from Newton’s’ demonstrations’ in optics. The British Journal for the Philosophy of Science, 51(1), 45–80.

    Article  Google Scholar 

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Patrick, K. Moderate Realism and Deduction from Truthlike Theories. J. Indian Counc. Philos. Res. (2022).

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  • Truthlikeness
  • Moderate realism
  • Scientific realism
  • Deduction
  • Eliminative induction