Suppose you doubt that rationally persuasive arguments can have just premises that are obviously false. But now consider:
(X) Grass is red.
Some arguments have merely obviously false premises.
'Grass is red' is the only premise and is obviously false, so (X) should convince you that there are arguments with merely obviously false premises. On the face of it, there is nothing irrational about being so convinced by (X). But then (X) is a rationally persuasive argument with merely obviously false premises.
A cheap trick you say? Not so, say I — a trick yes, but, I shall argue, far from cheap. In ' 'P, Therefore, P' Without Circularity,' Roy Sorensen uses numerous examples like these to suggest, among other things, that there is a missing parameter to argument evaluation, viz. exemplification. I shall argue, however, that understanding these sorts of cases in the way that motivates Sorensen to recommend adding the extra parameter has extremely unpalatable consequences. I shall propose an alternative account that avoids these consequences.
In section II, I shall present seven cases of what, following Sorensen, I shall call 'persuasion by exemplification' (Sorensen, 1991, 253), and then show that understanding these cases as Sorensen recommends has [End Page 235] extremely radical consequences for current views on the nature of arguments and what it takes for an argument to be rationally persuasive. In section III, I present and reject several options for how we might explain the cases so as to avoid the radical consequences. In section IV, I shall present and defend my preferred method for accounting for cases such as (X) — a method that does not require abandoning traditional accounts of arguments or their evaluation.
II Persuasion by Exemplification
Roy Sorensen, in several papers, uses cases such as the following primarily to support claims about the nature of circularity and begging the question.
(1) Begging the Question
Richard Robinson (1971) denies that there is a fallacy of begging the question. My rejoinder:
(A) There is a fallacy of begging the question.
Therefore, there is a fallacy of begging the question.1
(2) Premiseless Arguments
Many sensible people think that an argument must have premises. Not me. My rebuttal:
Therefore, there are arguments without premises.2
(3) P, therefore P
Many sensible people think that no argument of the form 'P, therefore P' is rationally persuasive. One of Sorensen's rejoinders:
(C) Some arguments are composed solely of existential generalizations.
Some arguments are composed solely of existential generalizations.3 [End Page 236]
(4) Black Ink
Many sensible people think that rationally persuasive arguments cannot have just obviously false and completely irrelevant premises. One of Sorensen's rejoinders:
(D) The moon is edible.
Some argument is written in black ink.4
Whether these examples serve to justify Sorensen's claims about circularity and question begging is not my concern here. But one secondary point that Sorensen makes with these cases is that there is a missing parameter to argument evaluation, viz. exemplification. The arguments made in (1) - (4), if they are rationally persuasive, rationally persuade because they exemplify the claim being argued for. Here are some additional cases:
(5) Fat, Liberal Bachelors
Some hold that all arguments are also explanations. Trudy Govier's (1987, 164) rebuttal:
(E) Jones is a Liberal.
Jones is fat.
Jones is a bachelor.
Therefore, Jones is a fat, Liberal bachelor.
Therefore, there are fat, Liberal bachelors.
So far all the cases have involved sentences or arguments exemplifying certain properties.5 But, of course sentences and arguments are not the only objects that can exemplify certain properties, and so persuasion by exemplification can occur via non-propositional examples as well.
(6) Judo Flip
Mark holds that no woman can overpower a man. Krista's rebuttal: [End Page 237]