Springer Nature is making SARS-CoV-2 and COVID-19 research free. View research | View latest news | Sign up for updates

Interactive virtue and vice in systems of arguments: a logocratic analysis

  • 101 Accesses


The Logocratic Method, and the Logocratic theory that underwrites it, provide a philosophical explanation of three purposes or goals that arguers have for their arguments: to make arguments that are internally strong (the premises follow from the conclusions, to a greater or lesser degree—greatest degree in valid deductive arguments), or that are dialectically strong (win in some forum of argument competition, as for example in litigation contests of plaintiffs or prosecutors on the one hand, and defendants, on the other), or that are rhetorically strong (effective at persuading a targeted audience). This article presents the basic terms and methods of Logocratic analysis and then uses a case study to illustrate the Logocratic explanation of arguments. Highlights of this explanation are: the use of a (non-moral) virtue (and vice) framework to explicate the three strengths and weaknesses of arguments that are of greatest interest to arguers in many contexts (including but not limited to the context of legal argument), the Logocratic explication of the structure of abduction generally and of legal abduction specifically, the concept of a system of arguments, and the concept of the dynamic interactive virtue (and vice) of arguments—a property of systems of arguments in which the system of arguments as a whole (for example, the set of several arguments typically offered by a plaintiff or by a defendant) is as virtuous (or vicious) as are the component arguments that comprise the system. This is especially important since, according to Logocratic theory (and as illustrated in detail in this paper), some arguments, such as abduction and analogical argument, are themselves comprised of different logical forms (for example, abduction always plays a role within analogical argument, and either deduction or defeasible modus ponens, always plays a role within legal abduction).

This is a preview of subscription content, log in to check access.


  1. 1.

    Throughout this essay I use a convention of using italics to name a word, letter, or phrase, as in word is the name of the word word, Logocratic Method is the name of the Logocratic Method. I use double quotation marks to indicate quoting an actual text or person (actual or hypothetical). Sometimes I use italics, as is also a convention, for emphasis. Context will indicate which is the use of a specific italicization.

  2. 2.

    At least superficially, I commit myself here to an ontology of abstract entities—proposition-types and argument-types. However, I neither have nor offer any deep commitment to this realist ontology, and believe that the references I’m making to abstract entities could be re-cast into a rigorous nominalist explanatory framework. For a robust defense of realism about types (of expressions), see Wetzel (2009). For a rigorous anti-realist nominalism, see Scheffler (1979).

  3. 3.

    I extend Skyrms (2000) at 15 (“Logic is the study of the strength of the evidential link between the premises and conclusions of arguments.”).

  4. 4.

    I label the premises of this argument ε1, ε2, and the conclusion as h, to keep before the Logocratic analyst the idea that, on the evidential conception of logic (see Sect. 2.1), premises of arguments are evidence for the conclusion as hypothesis (see also the definition of argument in Sect. 2.1).

  5. 5.

    See Dummett (1978) at 161 (“We have become so used to the cliché that inductive arguments establish their conclusions only with probability that we overlook the obvious fact that in practice we treat a great deal of inductive evidence as conclusive and a great many empirical statements which are not direct reports of observation as certain.”).

  6. 6.

    See Brewer (1988). This is a proto-Logocratic (Logocratic in basic method before I had explicitly framed the Logocratic Method) inferential account of interpretation.

  7. 7.

    See Nozick (1993) at 151–59.

  8. 8.

    There is also a Logocratic explanation of a special type of enthymeme that is of particular relevance to arguments about factual evidence of the sort that is the subject of legal doctrines of evidence. It’s called the evidentiary enthymeme, a device that explains the most common kinds of evidentiary arguments used in not only in law courts, but in every domain in which factual evidence is offered. Presenting that concept is beyond the scope of this essay, but see the detailed discussion in Brewer (2011, 2017a, b).

  9. 9.

    See Aristotle (1999).

  10. 10.

    See Raz (2009) at 224.

  11. 11.

    Phan Minh Dung offers an influential abstract model of dialectical competition of argument in the pioneering paper Dung (1995).

  12. 12.

    The Logocratic conception of rhetoric differs importantly from Aristotle’s, according to which rhetoric is defined as a theoretical discipline. See Aristotle Rhetoric (c. 335 B.C.E.; 2007) at 37–38. (“Let rhetoric be [defined as] an ability, in each [particular] case, to see the available means of persuasion….”) (citation omitted). From a Logocratic point of view, the referent of Aristotle’s domain of rhetoric is the study of rhetoric, not its practice.

  13. 13.

    We might say that the criteria of identity of each logical form is an ideal—something like a Platonic "Form". What distinguishes deductive, inductive, analogical, and inference to the best explanation arguments from each other are the ideal forms of those arguments.

  14. 14.

    I offer a concise Logocratic explanation of the characteristic virtues of all four modes of inference in Brewer (2017a, b) at 123–138. An even more recent treatment of the Logocratic account of abduction is in Brewer (forthcoming 2019). I offer a (proto-Logocratic–Logocratic in basic method before I had explicitly framed the Logocratic Method) account of both the structure and characteristic virtues and analogical argument (albeit without using that phrase) in Brewer (1996).

  15. 15.

    I draw the central idea for point of view from a model offered in the philosophy of science by Larry Laudan. See Brewer (1998). See also Laudan (1984).

  16. 16.

    I first articulated the idea of an enterprise conception of point of view in the (proto-Logocratic) article Brewer (1998). See the discussion there for further details.

  17. 17.

    I borrow from general systems theory, from Sampford (1989) at 11–23, and from Dewey (1902).

  18. 18.

    Dewey (1902). See also Sampford (1989) at 14.

  19. 19.

    Sampford (1989) at 14–15.

  20. 20.

    Dewey (1902).

  21. 21.

    I offer an example of chaining in explicating the basic structure of inductive specification in Sect. 2.5 above.

  22. 22.

    Howard (1980).

  23. 23.

    Howard (1980) at 1273.

  24. 24.

    Monge (1974). Monge is a favorite illustration for Logocratic analysis. See discussions in Brewer (2013) at note 16; Brewer (2017b) at 100, 104–110. We also use it as a central teaching tool in our annual Summer School on Law and Logic that we teach in Florence.

  25. 25.

    Monge (1974) at 553 (Grimes, J., dissenting).

  26. 26.

    Monge (1974) at 551.

  27. 27.

    A point about the Logocratic theory of abduction: every abductive-argumental claim that the latter is true presupposes the claim that the former is also true, but not vice versa.

  28. 28.

    Or, depending on one’s jurisprudential commitments, an application of defeasible modus ponens; I chose the deductive representation for reasons that I offer in Brewer (1996) at 989–1003.

  29. 29.

    Monge (1974) at 551. I make obvious assignments of propositional constants for a representation below using the grammar of non-modal, non-deontic propositional logic; B stands for the termination of and employee by the employer is motivated by bad faith, and for M, R, and E as indicated. Importantly, as a matter of fair interpretation I believe that the proposition is not in the best interest of the economic system or the public good is not intended to be part of the rule, but instead is part of the Monge court’s rationale for the rule. I have for this reason not included that proposition in my rulification of Monge.

  30. 30.

    I rulify the Monge rule as a monoconditional and not a biconditional because there are obviously other rules in the system whose consequent is E. However, in the context of Howard’s argument, the conditional functions as a biconditional, as explained below in note 35. In rulifying the Monge rule-enthymeme I am using the grammar of propositional deductive logic, see also Brewer (2017b), but in the text above I abbreviate the propositions that are named by the propositional constants 'B', 'M', that name an entire

  31. 31.

    For additional discussion of the Logocratic analysis of the burden of pleading in American law, see Brewer (2011) at 180, 182–83, 191–92.

  32. 32.

    For an early “proto-Logocratic” account of the role of lemmas in legal arguments, see Brewer (1998), Section VI.

  33. 33.

    For a detailed account of analogical and disanalogical argument, see Brewer (1996).

  34. 34.

    This has been called the sole sufficient conditionrule, namely, in the conditional α ⊃ β, if α is the sole sufficient condition for β, then it’s also a necessary condition for β. For the importance of this rule of interpretation for understanding the logic of legal argument, see Brewer (2017a) at note 6; see also Brewer (1998) at note 263.

  35. 35.

    For discussion of the characteristic virtues of dianalogical argument see (Brewer 2017a, b) pp. 137–38]


  1. Aristotle Nicomachean Ethics (1999) (c. 350 B.C.E.). Hackett, Indianaoplis Indiana, T. Irwin trans

  2. Aristotle Rhetoric (2007) (c. 335 B.C.E.). G. Kennedy, Aristotle, On rhetoric, a theory of civic discourse, Oxford, New York

  3. Brewer S (1988) Figuring the law: holism and tropological inference in legal interpretation. Yale Law J 97:823–843

  4. Brewer S (1996) Exemplary reasoning: semantics, pragmatics, and the rational force of legal argument by analogy. Harv Law Rev 109:923–1028

  5. Brewer S (1998) Scientific expert testimony and intellectual due process. Yale Law J 107:1535–1681

  6. Brewer S (2011) Logocratic method and the analysis of arguments in evidence. Law Probab Risk 10:175–202

  7. Brewer S (2013) Law, logic, and leibniz, a contemporary perspective. In: Artosi A, Sartor G et al (eds) Leibniz: logico-philosophical puzzles in the law: philosophical questions and perplexing cases in the law. pp 199–226

  8. Brewer S (2017a) Evident virtue: concepts and procedures of the logocratic method. In: Weinstein J, Abrams N, Brewer S, Medwed D (eds) Evidence cases and materials, 10th edn. Foundation, St. Paul, Minnesota, pp 10–24

  9. Brewer (2017b) Using propositional deductive logic as an aid to teaching American Contract Law: the logocratic approach. In: Krimphove D, Lentner GM (eds) Law and logic contemporary issues. Amsterdam U Press, pp 33–48

  10. Brewer (2019) Logic and the life of the law (Professor) a logocratic lesson from hohfeld (Yale U. Press forthcoming 2019)

  11. Dewey J (1902) System. In: Baldwin JM (ed) Dictionary of philosophy and psychology Vol. II. MacMillan, New York, p 659

  12. Dummett MAE (1978) Truth and other enigmas. Harvard, Cambridge, MA

  13. Dung PM (1995) On the acceptability of arguments and its fundamental role in nonmonotonic reasoning, logic programming and n-person games. Artif Intell 77:321

  14. Howard (1980) Howard v Dorr Woolen company 414 Atlantic 2nd, New Hampshire Supreme Court, pp 1273–1274

  15. Laudan L (1984) Science and values: the aims of science and their role in scientific debate. University of California, Berkeley

  16. Monge (1974) Monge v. Beebe rubber company 316 Atlantic 2nd, New Hampshire Supreme Court, pp 549–553

  17. Nozick R (1993) The nature of rationality. Princeton, New Jersey

  18. Raz J (2009) The rule of law and its virtue. In: The authority of law: essays on law and morality, 2nd ed. Oxford, New York, pp 210–228

  19. Sampford CJG (1989) The disorder of law: a critique of legal theory. Blackwell, Oxford

  20. Scheffler I (1979) Beyond the letter: a philosophical inquiry into ambiguity, vagueness, and metaphor in language. Routledge and Kegan Paul, London

  21. Skyrms B (2000) Choice and chance: an introduction to inductive logic, 4th edn. Wadsworth/Thomson Learning, Ontario

  22. Wetzel L (2009) Types and tokens: on abstract objects. MIT, Cambridge, MA

Download references

Author information

Correspondence to Scott Brewer.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Brewer, S. Interactive virtue and vice in systems of arguments: a logocratic analysis. Artif Intell Law (2019). https://doi.org/10.1007/s10506-019-09257-w

Download citation


  • Argument
  • Evidence
  • Logocratic
  • Virtue
  • Pragmatics
  • Inference