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Judging Rationally

Published online by Cambridge University Press:  25 February 2021

Barry Hoffmaster
Barry Hoffmaster, Professor Emeritus, Department of Philosophy, University of Western Ontario, Canada.
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Sophisticated realists, uncompromising positivists, and postmodernists created much of the law in the last century. Judges, lawyers, and philosophers now are continuing to clarify, improve, and use the law. The law is often clear. But it can be indeterminate because it is indefinite, indistinct, or vague. Two examples are provided.

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I am grateful to Cliff Hooker, Richard Bronaugh, Andrew Botterell, Dennis Patterson, Michael DeLaurentis, Gregory Kaebrick, Sylvie Lamer, and Nicolas Hoffmaster for their scrutiny of this paper and their astute criticisms and insightful improvements.


1. HLA Hart, The Concept of Law, 2d ed (Oxford University Press, 1994) at 8.

2. Brian Leiter, Naturalizing Jurisprudence (Oxford University Press, 2007) at 9 [emphasis in original].

3. Duncan Kennedy, “Toward a Critical Phenomenology of Judging” in Allan C Hutchinson & Patrick Monahan, eds, The Rule of Law: Ideal or Ideology (Carswell, 1987) 141. First published as “Freedom and Constraint in Adjudication: A Critical Phenomenology” (1986) 36:4 J Legal Educ 518.

4. Karl N Llewellyn, The Common Law Tradition (Little, Brown and Co, 1960), Appendix C: “Canons on Statutes” at 521-35.

5. Leiter, supra note 2 at 73-74.

6. According to Leiter, “the Realists … do not claim that the law is ‘globally’ indeterminate: they do not claim that the class of legal reasons fails to justify a unique outcome in all cases; rather it fails to do so ‘locally’, i. e., in a particular range of cases such as cases that reach the stage of appellate review.” Ibid at 41 [emphasis in original].


7. Brian Leiter, “Legal Formalism and Legal Realism: What is the Issue?” (2010) 16:2 Legal Theory 111.

8. Ibid at 111.


9. Ibid at 112.


10. Ibid at 111.


11. Ibid at 112.


12. DW Haslett, “What Is Wrong with Reflective Equilibria?” (1987) 37:148 The Philosophical Quarterly at 310.

13. Ibid [emphasis in original].


14. Ibid.


15. Leiter suggests that rationality could serve as a “normative ideal.” See Leiter, supra note 7 at 112.

16. Stephen Toulmin, Human Understanding (Princeton University Press, 1972) at 43.

17. Ibid at 44.


18. Nor, as Susan Haack has demonstrated, can the development of new logics beyond the “classical logic” of propositional calculus and quantification theory, such as modal logics, deontic logics, and relevance logics, rescue the identification of rationality with logicality. Susan Haack, “On Logic in the Law: ‘Something, but not All’” (2007) 20:1 Ratio Juris 1. “Something, but not nearly all” is more accurate.

19. Harold I Brown, Rationality (Routledge, 1988) ch 1.

20. Ibid at 19.


21. Antonin Scalia, “The Rule of Law as a Law of Rules” (1989) 56:4 U Chicago L Rev 1175.

22. Frederick Schauer, Thinking Like a Lawyer (Harvard University Press, 2009) at 96.

23. HLA Hart, “American Jurisprudence Through English Eyes: The Nightmare and the Noble Dream” (1977) 11:5 Ga L Rev at 971.

24. Schauer, supra note 22 at 125-26.

25. Hart, supra note 23 at 979.

26. Llewellyn, supra note 4 at 4.

27. HLA Hart, “Positivism and the Separation of Law and Morals” (1958) 71:4 Harv L Rev at 607-08.

28. Charles E Larmore, Patterns of Moral Complexity (Cambridge University Press, 1987) at 20.

29. Jerome Frank, Law and the Modern Mind (Stevens & Sons Limited, 1949) at xxvii. In addition, this quotation beautifully illustrates the reflexivity of non-formal reason. Non-formal reason is not just about improving the rationality of our judgment but also improving the rationality of our rationality.

30. The notion of reason as a regulatory ideal for judging is right, but the rule-application model of formal reason cannot serve that function because it is a degenerate idealization. In science an idealization is a model that is helpful because it simplifies a part of the real world by ignoring inessential information. Removing the effect of friction from the model of an inclined plane in physics, e. g., is a useful, simple, non-degenerate idealization for measuring acceleration down a plane. Doing so does not affect the fundamental underlying physical structure, so if necessary, the independent factor of friction can be restored to the model. With a degenerate idealization, removing a factor changes the underlying fundamental structure so that factor cannot be reinserted. Given its extensive simplification, formal reason is a degenerate idealization of rationality, and the rule-application of formal reason is, in turn, a degenerate idealization of judging. It can be pragmatically useful to treat a degenerate idealization as a simple idealization, but the history of theoretical accounts of judicial decision making manifestly demonstrates that that is not the case for the model of deriving uniquely correct decisions from rules. For discussions of these ideals and idealizations in science, see C A Hooker, Reason, Regulation, and Realism (State University of New York Press, 1995) at 52-53, 58-59, 307-08, 313-14, 318-26, and 350.

31. Richard A Wasserstrom, The Judicial Decision (Stanford University Press, 1960) at 23-24.

32. Explained in Barry Hoffmaster & Cliff Hooker, Re-Reasoning Ethics (MIT Press, 2018).

33. The classic film, 12 Angry Men, is a fictional depiction of non-formal reason in jury deliberation. I thank Arthur Yates, a former student, who brought this movie to my attention. See 12 Angry Men, directed by S Lumet (Orion-Nova Productions, 1957).

34. For theoretical accounts of judgment and non-formal reason, see Brown & Hooker, “Rationality as Effective Organisation of Interaction and Its Naturalist Framework” (2011) 21:1 Axiomathes 99.

35. See Frank, supra note 29, because, as Brown and Hooker explain, non-formal reason is needed to vindicate the rationality of science.

36. A Lippman-Hand & FC Fraser, “Genetic Counseling: Parents’ Responses to Uncertainty” (1979) 15 5C Birth Defects: Original Article Series 325; A Lippman-Hand & FC Fraser, “Genetic Counseling: Provision and Reception of Information” (1979) 3:2 American Journal of Medical Genetics 113; A Lippman-Hand & FC Fraser, “Genetic Counseling—The Postcounseling Period: I. Parents’ Perceptions of Uncertainty” (1979) 4:1 American Journal of Medical Genetics 51; A Lippman-Hand & FC Fraser, “Genetic Counseling—The Postcounseling Period: II. Making Reproductive Choices” (1979) 4:1 American Journal of Medical Genetics 73; A Lippman-Hand, “Communication and Decision Making in Genetic Counseling” in B Bonne-Tamir, ed, Human Genetics, Part B: Medical Aspects (AR Liss, 1982) 511.

37. Myra Bluebond-Langner, The Private Worlds of Dying Children (Princeton University Press, 1978).

38. Ibid at 155.


39. Ibid at 180.


40. Ibid at 188.


41. Hart, supra note 1 at 204.

42. Ibid at 205 [emphasis in original].


43. Frank, supra note 29 at 100.

44. Kennedy, supra note 3 at 141.

45. Kennedy is supposing that he is a judge in a trial court, not an appellate court. An enticing response to legal realism is to mitigate its damage to judging by confining indeterminacy, if not exclusively at least predominantly, to appellate courts. See Leiter’s discussion of legal realism (supra note 7 at 73-79) and Schauer’s discussion of Llewellyn (supra note 22 at 137-38). That proposal restricts indeterminacy to rule bewitchment, in particular, conflicts between and among rules. It ignores the fact skepticism of legal realism: the rampant indeterminacy in ascertaining the relevance of facts as well as rules. Appreciating fact skepticism would, it seems, suggest that there is more, not less, indeterminacy in trial courts because trial judges have to wrestle with both facts and rules. That is a mistake, however, because the relevance of facts and rules is not established singly, but jointly. Determining the relevance of facts or rules is a complex symbiotic process in which facts and rules interact dynamically, reciprocally, and reflexively. Kennedy nicely captures that process.

46. Richard A Posner, How Judges Think (Harvard University Press, 2008) at 214.

47. Ibid at 213.


48. Kennedy, supra note 3 at 146.

49. Ibid [emphasis in original].


50. John Stuart Mill, On Liberty (Bobbs-Merrill Co, 1956) at 55.

51. Kennedy, supra note 3 at 148.

52. Ibid [emphasis in original].


53. Ibid at 149.


54. Ibid.


55. Ibid at 150.


56. Ibid at 165.


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