... there are but three elementary kinds of reasoning. The first, which I call abduction ... consists in examining a mass of facts and in allowing these facts to suggest a theory. In this way we gain new ideas; but there is no force in the reasoning. The second kind of reasoning is deduction, or necessary reasoning. It is applicable only to an ideal state of things, or to a state of things in so far as it may conform to an ideal. It merely gives a new aspect to the premisses. ... The third way of reasoning is induction, or experimental research. Its procedure is this. Abduction having suggested a theory, we employ deduction to deduce from that ideal theory a promiscuous variety of consequences to the effect that if we perform certain acts, we shall find ourselves confronted with certain experiences. We then proceed to try these experiments, and if the predictions of the theory are verified, we have a proportionate confidence that the experiments that remain to be tried will confirm the theory. I say that these three are the only elementary modes of reasoning there are. (Peirce, 1905, ca., CP 8.209)
And later (p275):
“Abduction is the process of forming an explanatory hypothesis. It is the only logical operation which introduces any new idea” (Peirce, 1903a, CP 5.171; cf. also Peirce, 1901–2/1911, CP 2.777)This new idea is due to a form of creativity that Peirce describes as present in every act of perception (p282):
Looking out of my window this lovely spring morning I see an azalea in full bloom. No, no! I do not see that; .... That is a proposition, a sentence, a fact; but what I perceive is not proposition, sentence, fact, but only an image, which I make intelligible in part by means of a statement of fact. This statement is abstract; but what I see is concrete. I perform an abduction when I so much as express in a sentence anything I see. The truth is that the whole fabric of our knowledge is one matted felt of pure hypothesis confirmed and refined by induction. Not the smallest advance can be made in knowledge beyond the stage of vacant staring, without making an abduction at every step.
Perhaps the notion of abduction being present in any mode of perception is too closely stitched along Kantian interests in the distinction between Begriff und Anschauung (which, after all, it should not be forgotten, was developed to counter Humean scepticism, a book that famously had kept up Kant all night).
Perhaps a more productive mode of consideration would be to see this as a general way of hermeneutics. The issue of the circular nature of hermeneutics begins then to cash out more in the direction of iteration over the inductive supports that add plausibility to the initial abductive leap (and here, Alvirez Tucker is quite right, Bayesian modes of inference that explain how the probabilities of confirmation can be employed, can be plugged in quite readily).
For the purposes of the modeling of historical argumentation, this insight then can be translated as follows: We posit an event with Davidsonian structure and Schank-Abelsonian scripts associated at the type level. We then abduce these scripts in a forward fashion to generate our potential candidates for confirmatory verification. This forward generation may require the abduction of additional events, actors and materiel that have their own scripts associated with them.
All of this needs to be understood as embedded in a larger discourse that has participants and a pool of assumptions that function as "facts" in the discourse, i.e. we normally do not expect these to be called into question. Often these facts form the general basis upon which the abductive leap is even predicated (the things the abductive leap has to organize, as Peirce conceptualizes explanation), though Peirce is quite right that internally they are structured just as abductively. It is a convenience of the discourse and a simplification of the research tasks to hold them artificially as "understood", "agreed upon", "non-problematic" or "common knowledge" that need not be independently treated as up for grabs during the explanation phase. (However much later revisionism may expose that simplifying assumption as inaccurate.)
Notice that this model is left-recursive in so far as we can spend all of our time fleshing out the scenario into the minutest detail without ever getting to the point of verification. So some form of sensible heuristical iteration is required in practice, thereby limiting the accuracy of the reconstruction (we may never iterate to the winning posit).
No comments:
Post a Comment