Re: Limits in REL

Since I failed to add a comment to the previous posting about limits in REL, I take the opportunity to recall a nice remark of Aurelio Carboni: "REL has finite products and _weak_ equalizers. So you can take its exact completion. This happens to be the category of complete sup-lattices and sup-preserving maps. And the tensor product on REL extends to the exact completion." You can find more details in Anna Bucalo, G.R., Completions, comonoids, and topological spaces Annals of Pure and Applied Logic 137 (2006) 104?125 --Pino [For admin and other information see: http://www.mta.ca/~cat-dist/ ]