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Daily Telegraph 31/12/10
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tlanglet

Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills

Posted: Sun Jan 02, 2011 12:37 am Post subject:

daj95376 wrote:

Marty R. wrote:

And what have we concluded from this discussion?

1) That it's hard to argue with a chain:

Code:

(4=6)r6c5 - DP[(6)r6c46 = (25)r7c46+8] - (5=4)r7c5 => r2c5<>4

Danny, your comment suggests:

Corollary #1: A detailed process statement provides a useful result.

Corollary #2: A result without a detailed process statement is of questionable value.

Ted

ronk

Joined: 07 May 2006
Posts: 398

Posted: Sun Jan 02, 2011 4:39 am Post subject:

Marty R. wrote:

Quote:

Marty, one uses a DP by showing that all internal extra candidates individually lead to the same outcome. Alternatively, one can show that all potential external DP busters lead to a common outcome. Doing either would be using logical deduction, as opposed to induction.

Are you saying that your difference between deduction and induction can depend on the result, not just the process?

Yes. Using a DP, the invalidity IS the DP. There shouldn't even be a second one in the result IMO.

Marty R wrote:

Obviously, a 6 or 8 can kill this DP, so I test each one. (I still view this as a Forcing Chain except I found a place to start one rather than choosing one arbitrarily). So if a 6 and 8 produce a common outcome, that is logical deduction? If one leads to an invalidity, that's induction, presumably a finding with less cachet than the common outcome?

Pretty much, There is some loss of cachet when assertion of a candidate uncovers a DP, i.e., an invalidity with respect to a unique solution of a puzzle. However, there is considerably more loss of cachet when assertion of a candidate "crashes" the puzzle.

Marty R.

Joined: 12 Feb 2006
Posts: 5770
Location: Rochester, NY, USA

Posted: Sun Jan 02, 2011 6:05 am Post subject:

Well, this has been an interesting discussion, to say the least. I appreciate your insights.

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