Dan Rose

> pure and monotonic core Yes, I’m interested in what “pure” and “monotonic” *mean*. The guidance to stick to the parts of the language without sharp edges is helpful. But...

> You do need to read the links I provided to you. Not just cursorily. They pretty much answer what you get when you have pure, monotonic code. All full...

I rephrased my definitional question and moved it to StackOverflow: https://stackoverflow.com/questions/79612855/how-is-one-meant-to-parse-the-phrase-pure-monotonic-prolog

I did read the link, in detail, several times! It's excellent and explains some things quite well. You give *sufficient criteria* for "pure monotonic" Prolog. You don't give *necessary criteria*...

If the link you are telling me to read is [this one](https://old.reddit.com/r/prolog/comments/10nuwz8/what_exactly_is_the_pure_monotonic_core_of_prolog/j7p5rih/) then I *think* your definition of pure is "constructed of the safe parts of the language, given as...

> You are dipping in and out of the text. Cherry-picking. You're absolutely right. I skipped ahead here *and* reasoned, perhaps wrongly, that this was equivalent to the clpz characterization...

The central question I keep coming back to is "why say pure, monotonic Prolog" in the first place? It seems redundant, since pure (either by construction or by some tacit...

> Negation needs to be ruled out. I thought negation (as in `\+`) was already ruled out by purity since it’s defined using a cut! What did I overlook? Another...

Yes, cut clearly enables non-monotonic logic. That seems obvious. Are you saying that cut is pure?

This would be so much simpler had we started with a definition... > Pure does not imply monotonic. Negation needs to be ruled out. I think cut is impure (and...