[extropy-chat] Coin Flip Paradox

Jef Allbright jef at jefallbright.net
Wed Jan 31 18:44:35 UTC 2007


Gordon, just to get another calibration point, do you believe in the
validity of the principle of parsimony, aka Occam's razor? Or do you
possibly have a similar problem with it lacking a basis in logic?
- Jef

> -----Original Message-----
> From: extropy-chat-bounces at lists.extropy.org [mailto:extropy-chat-
> bounces at lists.extropy.org] On Behalf Of gts
> Sent: Wednesday, January 31, 2007 10:31 AM
> To: ExI chat list
> Subject: Re: [extropy-chat] Coin Flip Paradox
> 
> > That Bayes law cannot predict outcomes reliably in an
> > informational vaccuum is not at all a weakness of the
> > principle.
> 
> To be clear, I am not here arguing against Bayes' theorem.
> 
> I am arguing that the principle of indifference sometimes invoked
> by
> Objective/Logical Bayesians, (not to be confused with Subjective
> Bayesians), and by other logical theorists of probability (those
> who take
> after John Maynard Keynes) in the complete absence of information
> is not a
> principle of logic in the formal sense of that word.
> 
> Subjective Bayesians may use the same principle, but they are wise
> enough
> in my opinion to know better than to think the principle of
> indifference
> can be derived or supported by formal logic.
> 
> Think about it (and you too, Jef)...
> 
> On what logical grounds can proposition A imply or entail
> proposition B?
> 
> A: "No information is available about the true probabilities of the
> two
> possible outcomes X and Y."
> 
> B: "Outcomes X and Y are therefore equiprobable."
> 
> Does A imply B, logically? I think not! If you or Jef can show me
> otherwise then please do.
> 
> The principle of indifference looks to me like illogical hocus-
> pocus, pure
> nonsense left over from the naive theory of Laplace. It may still
> be
> useful as a heuristic device, but let's call a spade and spade
> here!
> 
> If the principle looks like a beautiful and elegant principle of
> logic to
> some people then, well, too bad for them. :)
> 
> -gts
> 
> _______________________________________________
> extropy-chat mailing list
> extropy-chat at lists.extropy.org
> http://lists.extropy.org/mailman/listinfo.cgi/extropy-chat




More information about the extropy-chat mailing list