> (a) There is more friction in the transition between hb* and nf* style
theorems

Could you elaborate on this? I would assume that once you have nfi and nfri
you can easily convert between the two styles.

On Sun, Sep 12, 2021 at 9:16 AM 'ookami' via Metamath <
[email protected]> wrote:

> Hi,
>
> I recently uploaded a couple of theorems to my Mathbox, starting with
> http://us2.metamath.org:88/mpeuni/wl-section-nf.htm, that demonstrate how
> things could have developed, if one had picked
> http://us2.metamath.org:88/mpeuni/nf2.html instead of
> http://us2.metamath.org:88/mpeuni/df-nf.html as the defining term for
> 'Not Free (Ⅎ)'.
> The results show, that one can expect in predicate logic an overall
> reduction of the usage of http://us2.metamath.org:88/mpeuni/ax-10.html,
> and perhaps a marginal decrease in use of
> http://us2.metamath.org:88/mpeuni/ax-12.html.
> This certainly positive result is due to the more symmetric structure of
> nf2 wrt to negation, and the avoidance of mixed quantified and not
> quantified variables. But it comes with a price, too. (a) There is more
> friction in the transition between hb* and nf* style theorems; (b) Axioms
> like ax-5 need the old style for full exploitation, so there is a sort of
> disruption in technique present.
> You will find more details in a
> http://us2.metamath.org:88/mpeuni/wl-section-nf.html.
> But these are my thoughts. Let me hear how you think about a change of
> definition of 'Not Free'.
> Wolf Lammen
>
> --
> You received this message because you are subscribed to the Google Groups
> "Metamath" group.
> To unsubscribe from this group and stop receiving emails from it, send an
> email to [email protected].
> To view this discussion on the web visit
> https://groups.google.com/d/msgid/metamath/65eeae41-40f2-40dd-9f36-2b8847c8b498n%40googlegroups.com
> <https://groups.google.com/d/msgid/metamath/65eeae41-40f2-40dd-9f36-2b8847c8b498n%40googlegroups.com?utm_medium=email&utm_source=footer>
> .
>

-- 
You received this message because you are subscribed to the Google Groups 
"Metamath" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to [email protected].
To view this discussion on the web visit 
https://groups.google.com/d/msgid/metamath/CAFXXJSuPXYD9QNCa77HNcgOtK1u%2BVOZQc1fek%2B0B9kjvXtsXLA%40mail.gmail.com.

Reply via email to