Discussions with and comments from Tony Cole and Victor Tadros were helpful; they were fun too. For written comments and clarifications on some issues (some of which did not make it to the final version) I thank Chad Flanders and Karim Youssef. I also thank an anonymous referee for helpful comments.

1. See Priel, Danny, ‘Farewell to the Exclusive-Inclusive Debate’ (2005) 25 Oxford J. Legal Stud. 675 at 676.CrossRefGoogle Scholar

2. See Priel, Danny, ‘The Boundaries of Law and the Purpose of Legal Philosophy‘ 27 L. & Phil. [forthcoming in 2008]Google Scholar, available at http://ssrn.com/abstract=1086389.

3. Kramer, Matthew H., ‘Why the Axioms and Theorems of Arithmetic Are Not Legal Norms’ (2007) 27 Oxford J. Legal Stud. 555 at 557.CrossRefGoogle Scholar

4. Ibid. at 557 note 9. Kramer follows here his earlier discussion in Kramer, Matthew H., Where Law and Morality Meet (Oxford: Oxford University Press, 2004) at 39–42, 92-95.Google Scholar

5. Kramer, supra note 3 at 557. Kramer then adds that it is also a norm if it ‘derives from a provenance that is regularly treated by the officials as a general source of binding bases for adjudicative decisions,’ and that in that case it is a norm even if it is largely ignored (see ibid. at 557). I believe this claim is problematic, but I will not discuss this matter here.

6. See Raz, Joseph, ‘Incorporation by Law’ (2004) 10 Legal Theory 1 at 15CrossRefGoogle Scholar; Raz, Joseph, The Authority of Law: Essays on Law and Morality (Oxford: Clarendon Press, 1979) at 46.CrossRefGoogle Scholar For my doubts about this argument see Priel, supra note 2 at 25.

7. Kramer, supra note 4 at 40 [emphasis added].

8. I raised this challenge in my review of Kramer’s book: Danny Priel, Book Review of Where Law and Morality Meet (2006) 69 Mod. L. Rev. 114 at 116.CrossRefGoogle Scholar

9. Kramer, supra note 4 at 92.

10. Kramer, supra note 3 at 562.

11. For statistical evidence showing that appeals to common sense are among the most common justificatory sources in American law see Allen, Ronald J., ‘Common Sense, Rationality, and the Legal Process’ (2001) 22 Cardozo L. Rev. 1417 at 1428-29.Google Scholar

Notice that I do not talk here about substantive common sense knowledge (these include basic notions of causation, space and time etc. and perhaps also certain moral maxims, such as that hurting people is prima facie wrong), but rather to common sense epistemic norms (common sense reasoning) about the appropriate ways of deriving conclusions from evidence. However, what I called ‘substantive’ common sense is also used to decide cases: juries rely on such norms in what is known as ‘jury nullification.’ In these cases jurors decide the outcome of cases by relying on certain non-legal norms to defy or challenge the law. Kramer’s definition is unclear on whether jurors on duty are ‘officials,’ but in any case juries’ reliance on such norms is recognized by many officials. See, e.g., Devlin, Patrick, Trial By Jury (London: Stevens, 1956) at 160–62.Google Scholar Again, these are free-floating norms that often justify legal decisions (for several examples see Cornish, W.R., The Jury, rev. ed. (Harmondsworth: Penguin, 1971) at 128–33)Google Scholar, even though they are not considered part of the law; indeed, these norms are thought to be contrary to the law

12. See Priel, supra note 8 at 116.

13. See Dworkin, Ronald, Justice in Robes (Cambridge, MA: Harvard University Press, 2006) at 234, 292 note 25.Google Scholar

14. Kramer, supra note 3 at 561.

15. Ibid. at 561 [emphasis added].

16. Kim, Cf. Jaegwon, ‘What is Naturalized Epistemology?’ (1988) 2 Phil. Perspectives 381 CrossRefGoogle Scholar: ‘It probably is only an historical accident that we standardly speak of “normative ethics” but not of “normative epistemology.” Epistemology is a normative discipline as much as, and in the same sense as, normative ethics’ (383). The sense is that epistemology is the attempt to explicate the standard for which beliefs we are ‘permitted’ to hold, which beliefs are ‘reasonable’ and which are ‘irre-sponsible.’ Ibid.

17. Shapiro, Stewart, The Philosophy of Mathematics: Structure and Ontology (New York: Oxford University Press, 1997) at 30 note 10.Google Scholar The preceding sentence is ‘the subject matter of mathematics is itself substantially normative, namely, correct mathematics, and good mathematics.’ Ibid. [emphases in original]. See also Fogelin, Robert, Walking the Tightrope of Reason: The Precarious Life of a Rational Animal (Oxford: Oxford University Press, 2003) at ch. 1Google Scholar (bearing the title ‘Why Obey the Laws of Logic?’).

18. See MacCormick, Neil, Legal Reasoning and Legal Theory (Oxford: Clarendon Press, 1978) at 19–72.Google Scholar

19. Lochner v. New York, 198 U.S. 45, 76 (1905) (J., Holmes, dissenting)Google Scholar; to the same effect Holmes, O.W, ‘The Path of the Law’ (1897) 10 Harv. L. Rev. 457 at 466Google Scholar (‘You can always imply a condition in a contract’). Some psychologists indeed argue that deduction plays an insignificant part in human reasoning. See in Oaksford, Mike & Chater, Nick, ‘Commonsense Reasoning, Logic, and Human Rationality’ in Common Sense, Reasoning, and Rationality, Elio, Renée, ed. (Oxford: Oxford University Press, 2002) at 174 CrossRefGoogle Scholar; see also Harman, Gilbert, ‘Rationality’ in Reasoning, Meaning, and Mind (Oxford: Clarendon Press, 1999) 9 at 27-28.CrossRefGoogle Scholar

20. See Gilbert Harman, ‘The Logic of Ordinary Language’ in Common Sense, Reasoning, and Rationality, supra note 19 at 94, 97-98. See also text accompanying supra note 11.

21. Kramer writes that the axioms and theorems of logic and mathematics are ‘universally quantified modal propositions which declare how things necessarily are.’ Kramer, supra note 3 at 559. But which things? On the difficulties with Kramer’s position see Benacerraf, Paul, ‘Mathematical Truth’ (1973) 70 J. Phil. 661 CrossRefGoogle Scholar; Benacerraf, Paul, ‘What Numbers Could Not Be?’ (1965) 74 Phil. Rev. 47.CrossRefGoogle Scholar There are also difficulties with what Kramer says here and elsewhere in the same essay about necessity, but I cannot address these issues here.

22. Kripke, Saul A., Wittgenstein on Rules and Private Language: An Elementary Exposition (Oxford: Blackwell, 1982) at 37.Google Scholar The discussion on the plus is found throughout the book, and as he stresses in other places ‘the meaning I assign to “+” is supposed to justify’ my ‘immediately and unhesitatingly calculating] “68+57” as I do’ (ibid. at 40) [emphases in original].

23. Ibid. at 53-54. See also the next Section where I argue that normative and descriptive are not opposite terms.

24. See Note, ‘ Looking it Up: Dictionaries and Statutory Interpretation’ (1994) 107 Harv. L. Rev. 1437 at 1438-40CrossRefGoogle Scholar. As the author notes ‘[i]n several … cases [decided by the United States Supreme Court in the preceding years], dictionary definitions were the primary determinant of the ultimate outcome’ (ibid. at 1440).

25. Marmor, Andrei, Positive Law and Objective Value (Oxford: Oxford University Press, 2001) at 71 CrossRefGoogle Scholar; under the name of the ‘separability thesis’ Kramer has defended an even stronger formulation, namely that there are no necessary connections between law and morality. See Kramer, Matthew H., In Defense of Legal Positivism: Law Without Trimmings (Oxford: Oxford University Press, 1999) at 196–97.Google Scholar

26. See Marmor, Andrei, ‘Legal Positivism: Still Descriptive and Morally Neutral’ (2006) 26 Oxford J. Legal Stud. 683 CrossRefGoogle Scholar; Coleman, Jules L., ‘Beyond the Separability Thesis: Moral Semantics and the Methodology of Jurisprudence’ (2007) 27 Oxford J. Legal Stud. 581 at 597-608.CrossRefGoogle Scholar

27. Kramer, supra note 3 at 561.

28. Ibid. [emphasis added].

29. For an argument that cognitivists should be descriptivists see Jackson, Frank, From Metaphysics to Ethics: A Defence of Conceptual Analysis (Oxford: Oxford University Press, 1998) at 113, 139-62.Google Scholar

30. Thus Kramer writes:

Supra note 3 at 561. I admit I was surprised to read this. Kramer has in the past enthusiastically endorsed Ronald Dworkin’s views on the nature of ethical statements. See Kramer, Matthew H., ‘Coming to Grips with the Law: In Defense of Positive Legal Positivism’ (1999) 5 Legal Theory 171 at 192-93.CrossRefGoogle Scholar He has even done so in the same book in which he discussed the notion of freefloating norms: Kramer, supra note 8 at 73 note 18. Yet in the piece Kramer so highly praised, ‘Objectivity and Truth: You’d Better Believe It’ (1996) 25 Phil. & Pub. Aff. 87, Dworkin explicitly rejects all forms of non-cognitivism (of which prescriptivism is a kind). Ibid. at 108-12. Dworkin calls the view he defends the ‘face value view’ of morality, ibid. at 127-28, according to which ‘murder is wrong’ means murder is wrong.

Of course, Kramer is entitled to change his view (in fact, I believe there are very good reasons for rejecting Dworkin’s views on metaethics), but then he must face up to the difficulties with his newly-adopted approach, not least that there are many moral sentences that could not be easily translated to prescriptive language. Think of ‘murder is worse than theft,’ ‘you should not do it because it’s wrong,’ ‘he was a good man.’ Sophisticated versions of non-cognitivism may address this and other problems, for example by saying that ethical language has both descriptive and prescriptive meaning (see Hare, R.M., The Language of Morals (Oxford: Oxford University Press, 1952) at 111–18)Google Scholar, or by explicitly stating that their project is reformist (see Gibbard, Allan Wise Choices, Apt Feelings: A Theory of Normative Judgment (Cambridge MA: Harvard University Press, 1990) at 153–55).Google Scholar But Kramer does not adopt these positions. (I don’t discuss here a more controversial challenge to his view, held by moral externalists, that ‘murder is wrong’ does not even entail ‘one should not murder.’)

31. See, e.g., Marmor, supra note 26; Hart, H.L.A., The Concept of Law, 2nd ed. (Oxford: Clarendon Press, 1994) at 239–44.Google Scholar

32. See Dickson, Julie, Evaluation and Legal Theory (Oxford: Hart, 2001)Google Scholar; Dickson, Julie, ‘Methodology in Jurisprudence: A Critical Survey’ 10 Legal Theory (2004) 117 at 125-26.CrossRefGoogle Scholar

33. Dickson, Evaluation and Legal Theory, supra note 32 at 45, 48-49, ascribes to John Finnis the view that there is ‘no place to stop’ between evaluation of importance and moral evaluation, and that ‘it just makes no sense to conceive of two different types of evaluation concerning features of the law [and that] … to evaluate something is to ascribe real value or worth to it, and this univocal meaning is the only one which the term will bear.’ This is not Finnis’s view. In fact, at one point he explicitly distinguishes between two kinds of evaluation. See Finnis, John, Natural Law and Natural Rights (Oxford: Clarendon Press, 1980) at 62 Google Scholar (‘To think of knowledge as a value is not, as such, to think of it as “moral” value’). Finnis’s argument is simply that we will have a better account of law if we included moral standards among our evaluative criteria for con-structing a theory of law. Nothing in the distinction between direct and indirect evaluation answers this claim.

34. Leiter, Cf. Brian, Naturalizing Jurisprudence: Essays on American Legal Realism and Naturalism in Legal Philosophy (Oxford: Oxford University Press, 2007) at 174–75.CrossRefGoogle Scholar I think Kramer expresses the same view when he says that the fact that epistemic norms are required to hold a belief are ‘no indication whatsoever of that proposition’s normative or non-normative status,’ Kramer, supra note 3 at 562.

35. I argue for both of them at length elsewhere. See, respectively, Priel, Danny, ‘Trouble for Legal Positivism?’ (2006) 12 Legal Theory 225 CrossRefGoogle Scholar; Priel, Danny, ‘Evaluating Descriptive Jurisprudence’ (2007) 52 Am. J. Juris. 139.CrossRefGoogle Scholar

36. More recently Raz seems to have weakened his claims. See Raz, supra note 6 at 17 (‘None of this proves that the incorporation thesis is false. But it raises serious doubts about it …. ’).

37. See, e.g., ‘the right to life is comprehensively protected under article 2 of the [European] Convention [on Human Rights] as incorporated in our law by the 1998 [Human Rights] Act.’ In re McKerr, [2004] UKHL 12, [2004] 1 WLR 807 at para. [51] (Lord Steyn). Lord Hoffmann expressed a different view in ibid. at para. [63], but his view (which in any case does not correspond to the notion of direction outside the law) is the minority view. For a recent invocation of the language of incorporation see R. v. Secretary of State for Culture, Media and Sport [2008] UKHL 15 at para. [44] (Lord Scott).

38. Crystal, Nathan M., Professional Responsibility: Problems of Practice and the Profession, 3rd ed. (New York: Aspen, 2004) at 17 [emphasis added].Google Scholar

39. Kramer might further complicate his analysis by saying that being free-floating is a necessary but not a sufficient condition for incorporation. If, plausibly, those further conditions include people’s attitudes, he would have to explain why those attitudes are not sufficient to decide the matter in the first place.

40. Foundations of Law 1980 §1, 34 Laws of the State of Israel 181. I have slightly altered the official translation.

41. I have been challenged that other inclusive positivists have no problem with this example, because they do not argue that morality is necessarily incorporated to the law, only that it can be. This may be so. What this means is that, at least on this matter, they accept my view that the boundaries of law are determined by the attitudes of legal practitioners. They should then explain why this is not true across the board.

42. Finch, Henry, Law, or a Discourse Thereof (originally published in law-French in 1627).Google ScholarPubMed The quote comes from the 1759 English edition (translated by Finch himself). The passage is ibid. at 6 (book 1, ch.3). A virtually identical passage appears in Finch, Henry, A Description of the Common Laws of England (1759) at 5.Google Scholar Though this book too was only published in English in 1759, it first appeared in law-French under the title Nomotechnia in 1613. Based on these passages I believe Finch deserves an honorary mention in the annals of interdisciplinary legal scholarship.

43. Stevens, Cf. Robert, Law and Politics: The House of Lords as a Judicial Body, 1800-1976 (Chapel Hill: University of North Carolina Press, 1978) at 77 Google Scholar (‘In the most general terms there was, during the nineteenth century, a march toward formalism [in English law]’).

44. Think for example of Karl Llewellyn’s view of ‘immanent law’ that was central to his design of the Uniform Commercial Code. See Danzig, Richard, ‘A Comment on the Jurisprudence of the Uniform Commercial Code’ (1975) 27 Stan. L. Rev. 621 at 624-27CrossRefGoogle Scholar; Whitman, James, ‘Commercial Law and the American Volk: A Note on Llewellyn’s German Sources for the Uniform Commercial Code’ (1987) 97 Yale L.J. 156.CrossRefGoogle Scholar In contrast, in seventeenth century England the Law Merchant was not considered part of the law, even though it was free-floating and frequently followed by the courts. See Baker, J.H., ‘The Law Merchant and the Common Law Before 1700’ (1979) 38 Cambridge L.J. 295 at 314-16.CrossRefGoogle Scholar In fact, when actual practice is closely considered it cannot be easily described as either incorporation or direction outside the law. See Baker, John, ‘The Law Merchant as a Source of English Law’ in The Search for Principle: Essays in Honour of Lord Goff of Chieveley, Swadling, William & Jones, Gareth, eds. (Oxford: Oxford University Press, 1999) 79 at 88–89, 95.Google Scholar

45. German Basic Law, Art. 1.

46. See Fuller, Lon L., The Morality of Law, rev. ed. (New Haven, CT: Yale University Press, 1969) at 128–29 Google Scholar, where Fuller argues, based on political considerations, that the rules of schools and universities should be considered part of constitutional law.

47. I argue at greater length for this conclusion in Priel, supra note 2. I also argue there that other questions, especially the explanation of law’s normativity, are different in the sense that they may be issues on which practitioners may be mistaken. The main difference between questions of boundary and the question of normativity is that the former are concerned with the scope of a certain practice, and therefore the answer to them is constituted by practitioners’ attitudes and actions. This is different from questions of normativity in which people’s attitudes about what makes the practice normative are not necessarily the best explanation of this aspect of law.

48. Kramer, supra note 4 at 38; see also ibid. at 230 (‘any protracted squabbling here at the level of terminology would be arid’).

49. This, I think, is the point in Green, Leslie, ‘General Jurisprudence: A 25th Anniversary Essay’ (2005) 25 Oxford J. Legal Stud. 565 at 579-80CrossRefGoogle Scholar, where he suggests that people may be wrong about what’s important or interesting. Green tells us of someone who suggested to Darwin that he should continue writing on pigeons, because no-one would be interested in The Origin of Species. But I think this example works against his argument: one sceptic notwithstanding, the importance of Darwin’s book was immediately recognized by both supporters and detractors, professional and lay. See Browne, Janet, Darwin’s Origin of Species: A Biography (London: Atlantic Books, 2006) at 1, 84-87, 99-101.Google Scholar This does not seem to be the case with regard to recent debates in analytic jurisprudence.

50. Gardner, Cf. John, ‘Legal Positivism: 5½ Myths’ (2001) 46 Am. J. Juris. 199 at 203.CrossRefGoogle Scholar

51. For related concerns see Frederick Schauer, ‘Is There a Concept of Law?’ available at http://www.lawucla.edu/docs/schauer.concept2.pdf. And for another call to connect jurisprudence with legal reality see Allan, James, ‘A Modest Proposal’ (2003) 23 Oxford J. Legal Stud. 197.CrossRefGoogle Scholar