Re: decisionmaking under uncertainty (was: global warming)

[Joseph Bellina <jbellina@SAINTMARYS.EDU>]

John's answer prompts me to comment that decision making in all science
is not the linear, logical sort of thing that the word "proof" implies.
I think it has much more in common with the kinds of things John is
suggesting.

Some time ago there was a thread about abduction, as distinct from
induction or deduction.  Abduction or hypothetico-deduction has built
into it the logical "weakness" of any inductive process...we never get
proof in the classical sense of demonstration which is essentially
deductive.  What we get is enough evidence that we are willing to say
something is likely true.

In the global warming case, it is therefore unreasonable to look for
proof, rather as has been pointed out, there is a growing set of
evidence that supports the notion that is likely true.  The more
evidence the more likely.

Of course if you do want to say something "is true", then you have, I
think overstepped the boundaries of science and moved to faith.  For me
going from "likely true" to "is true" is akin to jumping off a cliff in
the dark.

For what its worth,

joe

On Thu, 6 Feb 2003, John S. Denker wrote:

> Asking for _proof_ of global warming, or
> _proof_ of the opposite, is alas not the
> whole story.
>
> There are lots of problems (including at
> present the global warming question) where
> the methods of proof we use in the physics
> lab are not applicable.  There are a number
> of plausible outcomes, and no real proof that
> any of them are impossible.
>
> Situations like this are not the least bit
> uncommon.  Suppose you are a manager and you
> want to hire a researcher or two.  Can you
> _prove_ that they are going to work out?
> Invent something wonderful?  Win a prize?