Re: Unexpected Powerloom truth maintenance behavior....

On Aug 21, 2008, at 9:31 AM, Srini Ram wrote:

> (defmodule "TEST"
>   :includes ("PL-USER"))
> (in-module "TEST")
>
> ;(clear-module "TEST")
> (reset-features)
>
> (defconcept person (?x))
> (defrelation spouse ((?x person) (?y person))
>   :axioms (symmetric spouse))
>
> (assert (spouse jack jill))  ; expect (person jack) (person jill) to  
> be also asserted because of  domain of  person
>
> (ask (person jack))
> TRUE                                      ;; as expected
>
> (retract (spouse jack jill))          ;; expect (person jack) to  
> also be retracted by truth maintenance system
>
> (ask (person jack))
> TRUE                                     ;; unexpected
>
> Am I missing something.

No.  PowerLoom is missing something.
This is a bug.

I'm not sure about how to fix it, though.