On Tuesday, 7 November 2017 21:50:24 UTC, Dimitris Tsementzis wrote: > > Dan, > > It is an interesting idea to refer to univalence as a “mechanism” rather > than an “axiom”. > > Even if you did it for expository reasons, I believe that in certain > contexts it is a good phrase to adopt. > I very much like this way of expression, too, even though univalence became a mechanism for the first time with cubicaltt. Nevertheless, although Vladimir certainly didn't have a mechanism for univalence, he envisioned its possibility, and even formulated a conjecture that is still unsettled, namely that if univalence implies that there is a *number* n:N with a property P(n), then we can find, metatheoretically, using an algorithm, a *numeral* n':N (a closed term of type N) and a proof that univalence implies P(n'). No mechanism for univalence can currently provide that, as far as I know. Martin > > Dimitris > > On Nov 7, 2017, at 16:40, Daniel R. Grayson > wrote: > > See https://www.nature.com/articles/d41586-017-05477-9 > > -- > You received this message because you are subscribed to the Google Groups > "Homotopy Type Theory" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to HomotopyTypeThe...@googlegroups.com . > For more options, visit https://groups.google.com/d/optout. > > >