Re: Small probabilities

Dave,

I think your argument that we know someone intelligent did something with
the chess pieces is not quite the point I was making. The argument is
whether someone designed the _position_ to be one that was arrivable after a
sequence of legal (though bizarre) moves, and that you could deduce that
exact sequence, or whether the position was arrived at by some arbitrary
random process. I gave the example of a child playing with the pieces as
toy soldiers. But, as you say, the child might put the pieces on the
corners of the squares. If a monkey had had a go at it, many of the pieces
might be lying on their sides. But let's make the experiment more tight.

You have a computer program where you click a button on the screen and a
chess position is displayed. With 50% probability the computer generates a
position using random techniques. With 50% probability it loads up a
published retrograde analysis position. You look at the position on the
screen and you have to tell if it was the random position, or the retrograde
analysis position. I suppose you could say the non-puzzle was also designed
- someone had to write the computer program and design the algorithm for the
random number generator etc. But I'm talking about detection of the way the
chess position was designed - was there intentionality behind it, to produce
the puzzle, or was it a fluke of the random number generator? I believe
that if I did "solve the puzzle" I'd deduce on the grounds of probability,
that it wasn't the random number generator that did it.

You say it's possible, though unlikely that the thoughtlessly generated
position would correspond to a valid retrograde analysis puzzle. But where
do you draw the line in the sand? Given quantum mechanics, just about
everything is possible though unlikely. In "Hitchhiker's Guide to the
Galaxy", Douglas Adams humourously explored this with the notion of the
"Infinite Improbability Drive" (driven as I recall by a Brownian motion
generator in the shape of a cup of tea). Such a drive could, for example,
cause all the molecules in a party hostess's dress to appear 1 metre to the
right of where they should be. Such an event is possible, though extremely
unlikely. I'm guessing if you saw that you'd say it was a supernatural
miracle, even though it's possible.

Regards,
Iain

On 1/14/06, D. F. Siemens, Jr. <dfsiemensjr@juno.com> wrote:
>
> Iain,
> I find a problem with your example. Everybody knows that a chess board and
> the pieces are designed by intelligent individuals. No chessboard places
> itself on a table. No pawns or pieces jump out of the box and arrange
> themselves on the board. Even if they are lying helter-skelter, somebody
> dumped them out. So the only question is whether what we see by way of
> arrangement fits a specific category. Something with simple symmetry would
> likely not be a puzzle. It's more likely to involve an esthetic pattern. But
> it could be a highly sophisticated puzzle. Since I haven't played chess in
> decades, I'd be in no shape to determine it to be a puzzle. You might catch
> it, but there is no warrant that you would. You might not spot the strategic
> wrinkle involved. However, if the pieces were placed on the corners of the
> squares, we can be sure it is not something involving chess rules.
>
> On the other hand, although not common, there is no reason why a
> thoughtless placement may not produce a puzzle pattern. Unlikely is not
> impossible. Whatever the interpretation, we know that somebody did something
> with the chess set. This is radically different from determining whether
> there was a rational entity behind a pattern when the source is not already
> known. I have no trouble ascribing the patterns found in the universe to the
> Creator, but this is a matter of faith, not proof.
> Dave
>
> On Sat, 14 Jan 2006 17:42:39 +0000 Iain Strachan <igd.strachan@gmail.com>
> writes:
>
>
> Let's take a step back from Vernon's claim that this is a supernatural
> message that is being conveyed & just try to establish whether the patterns
> are intentional, or just a "surprising coincidence". I maintain that you
> CAN use small probabilities under certain circumstances to determine if some
> pattern was intentional, and this is the essence, as I understand it of
> "specified complexity" - the pattern has to be sufficiently pre-specified
> (ie you can't just say it's any old deal of bridge cards, but you have to
> predict what the next deal happens - though both events have the same
> probability, the predicted one is surprising because it was pre-specified).
> Similarly a pattern that is sufficiently simple doesn't merit a "designed"
> designation because there is in all probability a simple explanation.
>
> I'll use arrangements of pieces on a chess board as an example.
>
> If you walked into a room and found an empty chess board, then clearly
> this is a specified pattern of chess pieces on the board and one of low
> probability given all possible arrangements. But it is too simple to
> warrant any design inference. The simple explanation is the board is left
> there and no-one bothered to put any pieces out.
>
> Now consider the board arranged with a random layout of pieces, as if a
> child had been using the chessmen as toy soldiers (my son does this
> occasionally). The position isn't legal, both kings are in check, there are
> pawns on the first rank, or whatever. This position is complex, but not
> specified - it's effectively random.
>
> Now consider a class of chess position I'm very fond of trying to solve,
> called "retrograde analysis". A whole lot of these positions can be found
> at http://www.janko.at/Retros/. Typically you see a preposterous looking
> position on the board, but are told it is legal. The purpose of the problem
> is that you have to work out how the players got to this legal position by a
> sequence of moves from the beginning of the game. It is often amazing how
> much you can deduce about what went on previously in the game, which pieces
> must have been captured by which pawns, which pieces are promoted pieces,
> what the last move played must have been, and so forth.
>
> Such chess positions are so bizarrely contrived (they can be arrived at by
> a legal sequence of moves, but not a sensible sequence), that often they
> look very little different initially to the random layout of pieces I
> described that might have been set up by a child, or a monkey hitting a
> keyboard.
>
> Suppose you went into a room and the chess pieces were set up in a bizarre
> position that looked impossible. Your immediate impression would be that
> someone who didn't know the rules of chess had set the pieces up in a pretty
> pattern. But if you then analysed the position, and found that the position
> was indeed legal, and that you could make all these deductions about the
> contrived series of moves that would have been played to arrive at the
> situation.
>
> Would you not then be justified in deducing that the position had indeed
> been designed by a very clever person who knew the rules of chess? And if
> you were, what would be the basis of that deduction? I'd suggest it would
> be low probability. The number of possible arrangements of chess pieces on
> a chess board must vastly outweigh the number of arrangements of legal
> positions, and that in turn must vastly outweigh the number of positions
> that are suitable for retrograde analysis, where you can deduce e.g. what
> the last several moves must have been.
>
> Hence it is a small probability that determines design in this case. I'd
> be interested to know if you agree, or if maybe this is a good illustration
> of what Dembski means by "specified AND complex". Or would you perhaps say
> that even if you found such a position set up on a chess board, that there
> was no justification for concluding that the position was intentionally
> designed that way?
>
> Vernon's patterns, I would also say I believe to be both specified and
> complex, and that it was justifiable to conclude intentionality (let's leave
> open the question of whether it's a "message" for the moment).
>
>

--
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After the game, the King and the pawn go back in the same box.
- Italian Proverb
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