[FOM] Q

[Richard Heck]

Bill Taylor wrote:
> Robinson's Q, does not prove commutativity.
>
> Therefore, it must presumably have models where one or both of
> additive or multiplicative commutativity fail.
>
> Are there any "easy" models of this type?
>   
Yes. There are examples in Boolos[, Burgess, ] and Jeffrey. The point is 
that you can add non-standard elements quite freely, since there's not 
much to constrain their behavior.

Richard

-- 
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Richard G Heck, Jr
Professor of Philosophy
Brown University
http://frege.brown.edu/heck/
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