Re: Dembski's universal small probability bound

From: Richard Wein (rwein@lineone.net)
Date: Tue Jun 20 2000 - 12:12:04 EDT

  • Next message: Richard Wein: "Re: Dembski's universal small probability bound"

    Wesley, out last posts crossed.

    Wesley R. Elsberry wrote:

    >WRE>This does not mean that we actually believe it to be due to
    >WRE>chance, or that we consider the chance hypothesis sufficient
    >WRE>to the task. But like other forms of statistical inference,
    >WRE>chance gives us a null hypothesis to perhaps reject.
    >
    >RW>But you can't just calculate the probability of an event "as
    >RW>if it were due to chance". You need to assume a chance
    >RW>hypothesis. For example, the probability of rolling a 6 with a
    >RW>die takes a different value if I assume the die is fair than
    >RW>if I assume the die is biased in a particular way.
    >
    >In the case of testing a die for fairness, the relevant chance
    >hypothesis is that each possible outcome is equiprobable.
    >This is exactly how we do go about testing the fairness of
    >die, by detecting whether actual rolls of the die
    >significantly differ from our expectations of equiprobability.

    Fine, if you're testing dice for fairness. But what does that have to do
    with ID in nature?

    >IIRC, where Dembski does give examples of chance hypotheses in
    >TDI, they clearly are premised upon equiprobability of
    >outcomes.

    I would say that Dembski *wants* us to think that we only have to consider
    equiprobable (uniform) distributions. That may be why he only gives such
    examples. But the idea that only uniform distributions need to be considered
    *in general* is absurd. So we have a choice:

    a) We assume that Dembski really is making this absurd proposition. In which
    case you're right.

    b) We assume that Dembski stands by the general method described in TDI, and
    that his examples are not representative of the general case. In which case,
    I'm right.

    c) We point out that Dembski is wrong *either way*, while pressing him for
    an end to this equivocation.

    I recommend option (c).

    >I just noticed something that looks like an inconsistency in
    >terminology in TDI and Dembski's other essays.
    >
    >[Quote]
    >
    >For J to be constructible by means of logical connectives from
    >the same items of information out of which I is constructed is
    >what we mean by saying I <i>generates</i> J, or equivalently, J is
    ><i>generated</i> by I.
    >
    >[End Quote - WA Dembski, TDI, p. 149]
    >
    >In "Design as a theory of information" and in later discussion
    >of evolutionary computation, Dembski specifically denies the use
    >of "generated" or "generation" to cover the concept that a logical
    >transformation of prior information results in a different
    >arrangement of information afterwards.

    Yes, Dembski is using "generates" in two different senses. But I don't see
    that this is a problem. He keeps the two usages separate.

    In TDI, he's talking about generating a different set of information by
    logical deduction. For example, *I* might be the information "A=1", "B=2"
    and "C=A+B", while *J* is the information "C=3". Since *J* is logically
    deducible from *I*, no *new* information has been created.

    In "Intelligent Design as a Theory of Information", Dembski is referring to
    information generated by an *event*. This is new information, because it's
    not deducible from the information we had before (unless of course the event
    was 100% predictable, in which case it generates no new information).

    Richard Wein (Tich)



    This archive was generated by hypermail 2b29 : Tue Jun 20 2000 - 12:10:26 EDT