Re: Relational lattice completeness

Mikito Harakiri wrote:
> Jan Hidders wrote:
> > It is. Because we talking about a system where we have a semantical
> > notion of truth for algebraic identities and a syntactical one
> > (derivation from the set of given algebraic identies by applying them
> > to each other) and the question is if these two are the same.
>
> What makes your question hard is that the idea of formal derivation of
> algebraic identities is not mature enough yet.

I gave a nearly formal definition of what I meant with that term. I don't see how it can get more mature.

> Consider the chain of rewritings for push-select-through-project on
> page 7. On step 8 the Spight criteria is applied.

For the fragment that I asked about (look at the definition expression) the Spight rule is irrelevant.

• Jan Hidders