Clark, Danko, list,
From a Peircean standpoint, the question of an ontological basis for
abductive inference is only indirectly relevant, since it will be a case
wherein _/homo sapiens/_ is adapted to the more general requirements of
semiosis and inference. I.e., the requirements of semiosis, inference,
logic shape us. This is the kind of thing that Frederik (Stjernfelt)
points out. E.g., our actual Big-Bang universe is a place where
abductive inference is possible and is supported somehow, but that
doesn't tell us how abductive inference ought to be done - that remains
a pre-ontological question.
You wrote,
While not everyone would agree, I think Peirce is somewhat
influenced by virtue ethics with regards to abduction. Thus
abduction arises out of an optimistic development of an aesthetic
and ethical life. Abduction isn’t defined except in terms of the
practices of people who conduct good a[b]ductive reasoning. This
reasoning can’t be formalized however. It arises out of consciously
engaging with the living of each of our own lives and adjusting
ourselves as we live.
Peirce doesn't quite _/define/_ abductive inference in terms of the
practices of people who conduct good abductive reasoning. Most generally
he defines it as a conjecture that arises in the mind in order to
explain (successfully or not) a surprising phenomenon, and ultimately
concludes that abducing has very little to do with rules, and that the
pragmatic maxim is necessary and sufficient as a rule for it, to the
extent that it follows rules at all. He does offer particular forms of
abductive inference - in earlier years, a reordering of the Barbara
syllogism, and in 1903 another form. I agree that we should not regard
those forms as _/definitions/_ of abductive inference, but likewise I
think that we should not regard the Barbara syllogistic form as the
_/definition/_ of deduction.
Peirce also characterizes non-deductive inference as _/ampliative/_,
that is, having conclusions not deductively implied by the premisses,
and I still like the idea, that I had before reading Peirce, of
distinguishing induction from more 'leapy' or conjectural inference, by
whether the ampliative conclusion deductively implies the premisses or
not (I've tended in the past to speak of 'surmise' when I've had in mind
conjectural inference so defined, because I've doubted that people would
agree to define abduction as inference that lacks deductive implication
whether by premisses of conclusions or vice versa). Now, it's easy
enough to come up with an ampliative conclusion; such a conclusion
doesn't need abductive plausibility or Peirce's inductive verisimilitude
(the likeness of the conclusion to the premissual samples) in order to
be ampliative; but, without them, it just isn't intrinsically fruitful
or promising in inquiry. Likewise a deductive conclusion can simply
repeat a premiss word for word and still be deductive, but such a
deduction, lacking any new or nontrivial aspect, just isn't
intrinsically fruitful or promising in inquiry.
I tend to regard abduction's plausibility, natural simplicity, etc., as
on a par with Peirce's verisimilitude of induction and the new aspect or
the nontrivial aspect that a deductive conclusion may bring to its
premisses. Peirce doesn't mention instinct in connection with
induction's verisimilitude, and he only once, and briefly, so far as I
know discusses deduction's desirable 'new aspect' as a topic, although
he often discusses the difference between corollarial and theorematic
deduction. Peirce speaks despairingly of the prospect of finding a way
to quantify verisimilitude (or 'likelihood' as he also calls it there)
(1910, CP 2.663).
Really, none of these fruitful/promising aspects (nontriviality,
novelty, verisimilitude, plausibility / natural simplicity) lend
themselves to useful quantification, yet A.I. research could take some
sort of interest in all of them, since, if they were to be generally
absent, no mind would bother to infer. In the case of deduction, special
forms or schemata (e.g., the categorical syllogisms) are developed in
order to assure some modicum of novelty or nontriviality in deduction,
but how would one teach an A.I. what such novelty or nontriviality are?
How would it catch on to the idea in general? If an instinct is not
involved, then what is involved?
Arguably all of those aspects of promise in inference are
context-dependent, yet plausible abduction seems more context-dependent
than the others and, as you say, abductive reasoning arises out of
consciously engaging with the living of each of our own lives and
adjusting ourselves as we live. The areas of research that do much to
formally express abductive reasoning (if not under the label 'abductive
reasoning') are the special sciences. Yet I think that the question of
abductive plausibility is one of a family of related questions of the
inferential aspects of intrinsic promise in inquiry.
I'm not sure how to tie this sort of thing to a virtue ethics in a way
that distinguishes plausibility, or any of the promise aspects, from
other desirable things in inference - e.g., the recognition that A is A
can be taken as rationality as a virtue. Well, I guess all the promise
aspects could be taken as involving a virtue like you say of optimism,
or due confidence in spite of contrary pressure, in the process of
reasonabilization.
Best, Ben
On 4/2/2015 6:59 PM, Clark Goble wrote:
On Mar 26, 2015, at 3:21 PM, Benjamin Udell wrote:
Good texts by Peirce to read on abductive inference, besides his
discussion in his 1903 lectures on pragmatism, include "On the Logic
of Drawing Ancient History from Documents" (1901), Essential Peirce
v. 2, wherein Peirce gives one of his most systematic accounts of
abductive inference. He discusses instinctual plausibility,
instinctual naturalness (Galileo's "natural light of reason") of
abductive inference (or retroduction as he now called it) in "A
Neglected Argument for the Reality of God" (1908)
http://www.gnusystems.ca/CSPgod.htm#na0 in *Section III* and *Section
IV*.
In at least one writing, Peirce includes infantile training under
instinct. Still, the idea of instinct doesn't seem to tell the A.I.
researcher much about how to design an artificial intelligence that
can abduce well. I don't know how researchers have dealt with this.
I think this is the key problem. We’ve no idea how Peirce views these
things ontologically. Are they ontologically fundamental? Probably
not, although it’s hard to say given some of his later ontological
positions.
Instincts and intuition tend to be the “go to” for philosophers of
that era when they want something to be fundamental without explaining
it as such. (Think G. E. Moore on ethics for instance) Peirce doesn’t
really go that far, yet if you take say his Neglected Argument with
musements it seems he thinks we have some sort of access to things
that might not otherwise be apparent at first glance. Effectively his
use of abduction in the Neglect Argument suggests that abduction is
something basic and not really reducible to other means.
While not everyone would agree, I think Peirce is somewhat influenced
by virtue ethics with regards to abduction. Thus abduction arises out
of an optimistic development of an aesthetic and ethical life.
Abduction isn’t defined except in terms of the practices of people who
conduct good adductive reasoning. This reasoning can’t be formalized
however. It arises out of consciously engaging with the living of each
of our own lives and adjusting ourselves as we live.
Because abduction is tied so much to a virtue ethics which the
obtaining of habits through inquiry, attempting to explain it by a
formalism like Bayesianism or probably even neural nets or any other
computational scheme is doomed to failure. However in this it’s also
important not to reduce it (as many do) to a mere psychologism. If it
is a virtue ethics, it still is an ethics grounding a logic - of how
we ought reason.
-----------------------------
PEIRCE-L subscribers: Click on "Reply List" or "Reply All" to REPLY ON PEIRCE-L
to this message. PEIRCE-L posts should go to [email protected] . To
UNSUBSCRIBE, send a message not to PEIRCE-L but to [email protected] with the
line "UNSubscribe PEIRCE-L" in the BODY of the message. More at
http://www.cspeirce.com/peirce-l/peirce-l.htm .
