# Re: A Simple Notation

From: Vadim Tropashko <vadimtro_invalid_at_yahoo.com>

Date: Thu, 05 Jul 2007 09:30:57 -0700

Message-ID: <1183653057.985051.327010_at_q69g2000hsb.googlegroups.com>

Date: Thu, 05 Jul 2007 09:30:57 -0700

Message-ID: <1183653057.985051.327010_at_q69g2000hsb.googlegroups.com>

On Jul 5, 6:35 am, "David Cressey" <cresse..._at_verizon.net> wrote:

> But if the RA really is isomporhic to Bollean Algebra, then I'd like to

*> leverage what I think I do understand in order to better understand
**> something else.
*

RA is not isomorphic to Boolean Algebra. De Morgan/Pierce/Tarski relation algebra of binary relations is. There are 3 algebras on n-ary relations I'm aware of:

- Tarski Cylindric Algebras. Those seems to be very distinct from RA (because the relation dimension is fixed, and there is no named attribute perspective?)
- D&D <OR> & <AND> algebra. It is not boolean algebra because absoption law fails.
- RL. It is not boolean algebra because distributivity law fails.

Given that all 3 models have "flaws" that make them distict from boolean algebra, then obviously you'll experience difficulties reducing operator set to a single operator. Received on Thu Jul 05 2007 - 18:30:57 CEST