University Professor of Philosophy (emeritus), University of Windsor Fellow of the Royal Society of Canada (with Tony Blair), author of _Logical Self-Defense_ (1977, 1983, 1993; US edition 1994), organizer of three international symposia on informal logic (1978, 1983, 1989), editor of _Informal Logic_ (1978-present). author of _Manifest Rationality: A Pragmatic Theory of Argument_ (Lawrence Erlbaum Associates, 2000)
_Manifest Rationality: A Pragmatic Theory of Argument_
Sketch of a theory about how to analyse, evaluate and criticize arguments. Arguments are advanced in the context of a cultural practice of “argumentation” (= “the sociocultural activity of constructing, presenting, interpreting, criticizing and revising arguments” (12)). Its fundamental characteristics (159-164): teleological (goal of rational persuasion), dialectical (arguer lets feedback from the Other affect the argument), manifestly rational (patently and openly rational). Proposed revision of goal of participants: “arriving at a shared rationally supported position on an issue” (David Hitchcock, “The practice of argumentative discussion,” _Argumentation_ 16 (2002), p. 291. Revision accepted by Ralph Johnson (“Manifest rationality reconsidered”, _Argumentation_ 16 (2002), p. 313). Rational = able to give and receive reasons (14); disposed to use, give and act on the basis of reasons (161) Argument = “a type of discourse or text–the distillate of the practice of argumentation–in which the arguer seeks to persuade the Other(s) of the truth of a thesis by producing the reasons that support it. In addition to this illative core, an argument possesses a dialectical tier in which the arguer discharges his dialectical obligations.” (168) Revision by Johnson (2002, p. 316): .. a paradigm case of an argument possesses a dialectical tier. Dialectical obligations: deal with known alternative positions and known objections (165, 318) as well as with criticisms, and with implications and consequences of the position. Theory of evaluation (chapter 7, below) provides criteria for evaluation of both the illative core and the dialectical tier. Theory of criticism (use of evaluation to provide feedback to the arguer) includes four principles: vulnerability (make your argument vulnerable to criticism, p. 324), parity (any legitimate line of reasoning or argument that one party can use the other can too, 236), logical neutrality (do not pass off substantive criticism as logical criticism, p. 237), discrimination (display balance [focus on both strengths and weaknesses], perspective [focus on most important problems] and integration [structure to give greatest weight to most major criticisms], p. 241).
"What makes a good argument? Toward a theory of evaluation" (chapter 7)
The illative core must meet the following requirements (190_191) [NB to which components of the illative core each requirement applies]: I1. rational acceptance (acceptability) of each premiss: an argument will not achieve its goal of rational persuasion if the other does not accept the premisses but, in order for the persuasion to be rational, the acceptance must be rational (191_195) [NB: ‘Acceptability’ is ambiguous between ‘accepted’ and ‘worthy of acceptance’; Johnson fuses the two senses into a single concept of rational acceptance. The burden of proof lies with the arguer to provide support for any premiss that the intended audience will not accept without support.] I2. truth of each premiss: it would not be rational to accept a false premiss as a basis for accepting the conclusion and people presuppose a truth requirement in their evaluations (195_198) Here Johnson is rejecting Hamblin’s attempt to replace a truth requirement on premisses with an acceptance requirement (182-189) and is instead adding to the requirement of (rational) acceptance of each premiss a requirement that each premiss be true. [NB: Johnson does not define acceptability in terms of truth; they are independent criteria. Comment by Leslie: Johnson recognizes degrees of truth (T2, p. 198), but does not define what degree of truth a premiss must have.] I3. relevance of each premiss or each premiss set or the premisses as a whole [NB variability of its inherence] to the conclusion: an assertion or set of assertions does not deserve to persuade the other of the conclusion if it has no bearing on the conclusion, and the idea that one statement is a reason for accepting another implies that the first is relevant to the second (199-204) [NB: Relevance is independent of truth; a premiss can be relevant even if it is not true. Premiss relevance can however be defined in terms of truth, as the property of bearing on the truth of the conclusion if it is true.] I4. sufficiency of the premisses taken together [NB]: premisses meeting the previous three criteria will fail to persuade rationally if they do not provide (at least) enough types of evidence and enough evidence of each type (204-205) Whether these individually necessary conditions are jointly sufficient is the completeness problem (206). Reflective question (Leslie): Why does Johnson present the criteria first in the order RSAT (180), then in the order ATRS (191)? Reflective question (Leslie): Does the order matter to the evaluation process? Reflection (Patrick): Johnson’s case for the truth of each premiss as a requirement of a good argument has both a dialectical tier (responding to Hamblin’s alternative position and objections) and an illative core Reflection (Patrick): Johnson’s objection to the example that Hamblin uses to object to truth as a requirement (namely, the objection that the problem with a premiss addressed to ancient Romans that mentions Romans does not mention vitamins) can be met by providing another example of a premiss that is intelligible to its audience but is unacceptable even though true: the proposition in an argument in the middle ages that the sun does not revolve around the earth. Reflection (Khameiel): Johnson’s critique of Hamblin’s substitution of acceptance for truth misses the mark because they have different conceptions of the aim of argument, as well as different questions (descriptive vs. normative), and Hamblin’s point is not a rejection of truthfulness but a claim that in the context claiming truth amounts to no more than acceptance. Reflection (Kelly): Hamblin’s statement that to an onlooker my statement that so-and-so is true is simply a statement of what I accept ought not to be accepted without further support, since the statement seems to reflect anecdotal evidence from personal experience or impressions of the function of such statements in regular conversation, and anecdotal evidence is highly suspect. Reflection (Kelly): Johnson’s addition of truth of each premiss seems superior to Hamblin’s substitution of acceptance, since it guards against an argument with false premisses being a good argument, whereas Hamblin’s criterion does not. Reflective question (Nancy): If the concept of truth is implicit in our conceptions of acceptability and relevance, can we incorporate the truth requirement implicitly without having it as a separate criterion? Reflective question (Nancy): What is truth? Who decides what it is? If it is just another name for what is agreed upon, it is the same as acceptability. If there is an absolute Truth (capital ‘T’), how will we all come to know it?
As for the dialectical tier, it must meet the following requirements for “global sufficiency” (Logical Self-Defense, United States edition [New York: McGraw-Hill, 1994], p. 75) [NB the three types of components]: D1. the arguer must be able to deal well with the standard objections to the premisses and with other criticism (207) D2. the argument should address itself well to alternative positions to the one argued for (207-208) D3. the argument should deal well with consequences and implications of the position (208) Reflection (Nancy): If we are going to include the dialectical tier as an evaluative requirement, we must indicate what depth the arguer must go to in constructing it. (Cf. pp. 327-333.)