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Re: What to call this operator?

From: Vadim Tropashko <vadimtro_invalid_at_yahoo.com>
Date: 1 Jul 2005 11:18:42 -0700
Message-ID: <1120241922.484345.277120@z14g2000cwz.googlegroups.com>


Mikito Harakiri wrote:
> "there exists employee x and department y such that x works in y
> AND
> there exists department y and manager z such that y is led by z"
>
> which can be reduced to
>
> "there exists employee x, department y, and manager z
> such that x works in y and y is led by z"

Quantifies are subtle entities. I don't think

"there exists employee x and department y such that x works in y AND
there exists department v and manager w such that v is led by w"

is logically equivalent to

"there exists employee x, department y, and manager z  such that x works in y and y is led by z"

I renamed bind variables in the second half of the first sentence to make this obvious. Received on Fri Jul 01 2005 - 13:18:42 CDT

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