Subject: Re: [lojban] polyadic connectives

From: Robin Lee Powell <[email-masked]>
Date: Fri, 17 Aug 2001 20:33:21 -0700

On Sat, Aug 18, 2001 at 04:22:09AM +0100, And Rosta wrote:
> There was some recent discussion, instigated by pc, about more-than-binary
> connectives. For some, like an extended xor, it's easy to see how to
> render them: "exactly one of A, B, C is true". 

Umm, no.

IIRC, this is even mentioned in the book as an example of one that
doesn't work. Here's the table, assuming left associativity:

A xor B Result C
T F T T T
T F T F F
T T F F T
T T F T F
F T T F T
F T T T F
F F F T T
F F F F F

IOW, it's true when exactly one is true and when all are true. Rather
counter-intuitive.

-Robin

-- 
http://www.digitalkingdom.org/~rlpowell/ BTW, I'm male, honest.
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