Re: curiousity of sets of no relations?

From: paul c <toledobythesea_at_oohay.ac>
Date: Sat, 10 Jun 2006 16:42:16 GMT
Message-ID: <IDCig.4878$iF6.4180@pd7tw2no>

Bob Badour wrote:
> paul c wrote:
>

>> ...
>> That seems a practical motivation.  In terms of relations and/or set 
>> theory/predicate calculus can anybody give a more theoretical one?

>
> He simply defined them as the identity elements for the specific
> operations just as one defines any aggregate/fold of zero elements using
> the identity element for the base operation.

In other words, I'm guessing, "to make it all work/to guarantee the ops always return relations", i.e., the motivation is practical only, analogous to notions such as the "empty product" (such as in http://en.wikipedia.org/wiki/Empty_product)? If so, I think I'm content with that, e.g., thinking of the empty set as just a gizmo to enable various operations we desire.

p Received on Sat Jun 10 2006 - 11:42:16 CDT