Search All of the Math Forum:

Views expressed in these public forums are not endorsed by NCTM or The Math Forum.

Notice: We are no longer accepting new posts, but the forums will continue to be readable.

Topic: SET THEORY and QUANTIFIER LOGIC are SUPERFLUOUS! You only need
1 or the other!

Replies: 8   Last Post: Nov 22, 2012 4:20 PM

 Messages: [ Previous | Next ]
 Dan Christensen Posts: 8,219 Registered: 7/9/08
Re: SET THEORY and QUANTIFIER LOGIC are SUPERFLUOUS! You only need 1
or the other!

Posted: Nov 22, 2012 2:39 PM

On Nov 20, 4:09 am, Graham Cooper <grahamcoop...@gmail.com> wrote:
> The notation in
>
> { x | p(x) }
>
> stands for ALL VALUES OF x
> that are satisfied in p(x)
>
> This is the SAME 'ALL' as   ALL(x) ....predicate(..predicate...
> x  ...) ...)
>
> ALL is merely SUBSET!
>
> ALL(n):N  n+1 > n
>
> is just
>
> { n | neN }  C  { n | n+1>n }
>
>

How do you propose to do proof by induction e.g. prove 1+2+3+...+n =
n(n+1)/2?

Dan

Date Subject Author
11/20/12 Graham Cooper
11/20/12 Frederick Williams
11/20/12 Charlie-Boo
11/20/12 Frederick Williams
11/22/12 Dan Christensen
11/22/12 Graham Cooper
11/22/12 Graham Cooper
11/22/12 Graham Cooper