----- Original Message ----- From: "Donal McEvoy" <donalmcevoyuk@xxxxxxxxxxx>
To: <lit-ideas@xxxxxxxxxxxxx> Sent: Tuesday, September 29, 2009 6:23 PM Subject: [lit-ideas] Re: The Educational Value of Slips of the Whatever --- On Tue, 29/9/09, Richard Henninge wrote:
I pray, and I think we should all so pray that Donal is indeed "mistaken" that "any assertion, including those as to the validity of deductive inferences, is possibly or potentially mistaken." This is an extremely radical position, fit, metaphorically speaking, to put quicksand under the basis of all our mutual understanding, unless Donal is saying, in effect, "not to worry--even if a given assertion as to the validity of deductive inferences is mistaken, that would not preclude the validity of deductive inferences so asserted."
Comments:1. The last statement does not follow from the premiss I used: from the fact that the validity of a (putative) deductive inference "is possibly or potentially mistaken" (my premiss) we cannot leap to the conclusion that it "is mistaken" (Richard's conclusion).
... Two comments:1a. It can no longer be glancingly admonished as a "slip of the whatever" when an interlocutor misstates his own premisses, including the unacknowledged singularizing of his originally sweeping generalization ("any assertion, including those as to the validity of _deductive inferences_, ... ) and the unacknowledged replacing of his original "any assertion ... as to the validity of" by the completely different "fact of the validity of ... " what has now become his singular and parenthetically qualified "(putative) deductive inference."
2a. Furthermore, the conclusion I supposedly leap to is just the opposite of what Donal credits me with claiming. I do not say that "Donal says, in effect" that the _assertion_ of the validity or invalidity of deductive inferences makes them so, makes them valid or invalid, but that such assertion leaves them cold, so to speak, and hence does not "preclude" their validity or invalidity. I in no way say either that, because (as Popper says) the assertion of the validity of deductive inferences or (as Donal is now saying) the actual validity of those deductive inferences "is possibly or potentially mistaken," _either_ that the assertion of their validity _or_ that their actual validity "is mistaken." What I disagree with is the use of the word "validity" as, in some way, scalar. If this so-called validity is historically conditioned or if it can be impinged upon by such life-and-death scenarios as those proposed by Donal, or if this validity _can be_ mistaken, it seems to me it must be of an entirely different category than logical statements of the sort, "if P & Q, then Q." It's the putting in question of the validity of _that_ (remember, "... any assertion ...") that makes me wonder what intelligent discussion is going to look like without some such necessary logical infrastructure.
Richard Henninge University of Mainz ------------------------------------------------------------------ To change your Lit-Ideas settings (subscribe/unsub, vacation on/off, digest on/off), visit www.andreas.com/faq-lit-ideas.html