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Re: NULLs: theoretical problems?

From: Lennart <erik.lennart.jonsson_at_gmail.com>
Date: Fri, 10 Aug 2007 06:20:47 +0200
Message-ID: <f9gp30$hs3$1@registered.motzarella.org> 





David Portas wrote:


[...]


> Good catch. It seems that logical implication is not well defined for 

> three-value logic. According to Lex de Haan and Toon Koppelaars' recent 

> book:

> 

>  P | Q | P->Q

> --------------

>  T | U | U

>  F | U | T

>  U | T | T

>  U | F | U

>  U | U | U or T?

> 




Why would U->U possibly be T?




/Lennart



[...]
Received on Thu Aug 09 2007 - 23:20:47 CDT












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