Date: Nov 27, 2012 4:38 PM
Author: Robert Hansen
Subject: Re: Some important demonstrations on negative numbers

On Nov 27, 2012, at 4:11 PM, Clyde Greeno @ MALEI <> wrote:

> As Joe hinted, there are many real-world contexts in which both kinds of operations are common-sensible. Formal proof is not one of them.

Again, there is another layer below all that. We call that layer "mathematics".

Bob Hansen