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To: AndrewC

Speaking of Bertrand Russell, why did he and G.E. Moore choose Not and And for their reduced forms? Your Nand and Nor would have been more "economical" in terms of operators. (The CRAY-1 used only a 5-4 Nand gate for logic; plus memory and register chips. Three types of chips, off the shelf.) Modern books prefer And, Or, Not, Implies, and Equivalent, because these seem to be easier to read. Principia Mathematics is hard to read more because of the choice of notation that because of the difficulty of its proofs.


19 posted on 05/18/2004 9:20:49 PM PDT by Doctor Stochastic (Vegetabilisch = chaotisch is der Charakter der Modernen. - Friedrich Schlegel)
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To: Doctor Stochastic

I think your discussion hits the mark. Our means of communication already is prejudiced towards 'not', 'and', and 'or'. We use a conjunction of two to describe the sufficient operators, not or = nor, not and = nand. Mendelson in "Introduction to Mathematical logic" calls them 'joint denial' and 'alternative denial'.


21 posted on 05/18/2004 9:30:52 PM PDT by AndrewC (I am a Bertrand Russell agnostic, even an atheist.</sarcasm>)
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To: Doctor Stochastic
Principia Mathematics is hard to read more because of the choice of notation that because of the difficulty of its proofs.

I've heard it said only two people understand Principia Mathematica, and both of them are dead. :-)

24 posted on 05/18/2004 9:49:46 PM PDT by LibWhacker
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