Re: A question on Dawkins

Stephen Jones (sjones@iinet.com.au)
Fri, 26 May 95 06:53:51 EDT

Murray

On Wed, 24 May 95 09:34:08 +1000 you wrote:

>> "To 'tame' chance means to break down the very improbable into less
>> improbable small components arranged in series. No matter how
>> improbable it is that an X could have arisen from a Y in a single
>> step, it is always possible to conceive of a series of infinitesimally
>> graded intermediates between them. However improbable a large-scale
>> change may be, smaller changes are less improbable. And provided we
>> postulate a sufficiently large series of sufficiently finely graded
>> intermediates, we shall be able to derive anything from anything
>> else"*
>> (Dawkins R., "The Blind Watchmaker", 1991, Penguin, p317).
>
>Pardon my possible ignorance of the subtleties involved here, but I keep seeing
>this quote, and I keep thinking *it just ain't so* - perhaps someone can
>explain what I am missing (I assume Dawkins hasn't made the basic mistake I am
>about to accuse him of)
>
>If one takes 100 dice, rolls them all at once, the probability of getting 100 x
>sixes is pretty low (1/6 ^ 100). *Ah, but,* says Dawkins, *a SINGLE six is
>much more likely - only 1/6 - THUS if we roll a single dice 100 times we are
>more likely to get 100 x sixes.* Now, as I say, this just ain't so, but it
>appears to me that this is exaclty what Dawkins is saying. What am I missing,
>or is he indeed plain wrong?

Dawkins is "plain wrong", as has been pointed out by Milton:

"Dawkins' argument is a modern rendition of the traditional Darwinist
approach and the error it falls into is that dubbed the 'Statistical
Fallacy' by Francis Crick...Suppose we have a highly improbable event
such as a perfect deal in bridge, where each of the four players
receives a complete suit of cards. The odds against this happening
are billions of billions of billions to one. Let us assume that since
being manufactured the cards have been used for 99 deals and on the
100th time the pack was shuffled, the perfect deal arose. Can we say
that each of these previous shuffles, deals and plays of hands (number
1 for instance) was a cumulative event that ultimately contributed to
the perfect deal? Can we reduce the ultimate odds against the perfect
deal by attempting to spread them around more thinly between the
intermediate steps? Not afterwards, note, when we know the result,
but at the time each step is occurring?

The answer is no, we cannot. Like the supposedly evolving DNA, the
cards have a memory in that the previous deals have contributed to
their current order and the ultimate perfect deal. But being part way
towards a perfect deal does not alter the odds on the ultimate deal,
because some of the key random events determining the ultimate outcome
have not yet taken place."

(Milton R., "The Facts of Life: Shattering the Myth of Darwinism",
Fourth Estate, London, 1992, p143)

With this fallacy Dawkins' whole argument fails. And with it his whole
Blind Watchmaker thesis.

Stephen