On Dec 4, 2:52 am, Bruno Marchal <marc...@ulb.ac.be> wrote: > I just said that if M1 < M2, then M1 [=] M2. This means that M2 needs > higher order logical formula to be distinguished from M1. > Elementary embeddings (<) are a too much strong notion of model > theory. It is used in context where we want use non standard notions, > like in Robinson analysis.

Doesn't the archemedian property show that R is not elementarily equivalent to R*? I mean the following 1st order formula true in only one of R and R*: for all X there is a Y such that (Y is a natural number and X<Y) This is true in R but not in R*. This would appear to me to be an example of why R is not [=] to R*. -- You received this message because you are subscribed to the Google Groups "Everything List" group. To post to this group, send email to everything-l...@googlegroups.com. To unsubscribe from this group, send email to everything-list+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/everything-list?hl=en.