Ray & Maree Ludenia wrote: > David Hobby wrote: >> Another place where this kind of thing shows >> up is in the definition of the natural numbers. >> Do they start at 0 or at 1? On a basic level, >> starting at 1 makes sense. But in set theory >> (or computer science) starting at 0 works better. >> > > David, > I was only a maths teacher in an Australian High School, but we taught that > natural numbers start at 1. If you want to include 0 then they were called > whole numbers. It is only a name after all, but we were careful to make that > distinction to 12 year old students. Do they make the same distinction here?
Maree-- Hi. If you're teaching that the natural numbers start at 1, then "whole numbers" is what you call the set that includes 0. That usage is standard at the high school level. Back to what I was saying about Wikipedia, the article there at http://en.wikipedia.org/wiki/Natural_number starts like this: > In mathematics, a natural number (also called counting number) can > mean either an element of the set {1, 2, 3, ...} (the positive > integers) or an element of the set {0, 1, 2, 3, ...} (the > non-negative integers). The latter is especially preferred in > mathematical logic, set theory, and computer science. I often teach upper division college Math courses that are just at the cusp between the two definitions, and make a point of stating the definition of the natural numbers. (Whatever it says in the text, of course!) ---David Positive integers, Maru _______________________________________________ http://www.mccmedia.com/mailman/listinfo/brin-l
