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Topic: Is it possible that 3+4=8?
Replies: 21   Last Post: Jan 29, 2011 9:06 AM

 Messages: [ Previous | Next ]
Re: Is it possible that 3+4=8?
Posted: Jan 24, 2011 7:26 AM

On Jan 24, 11:02 am, LudovicoVan <ju...@diegidio.name> wrote:
> On Jan 23, 8:31 pm, LudovicoVan <ju...@diegidio.name> wrote:
>

> > On Jan 23, 7:47 pm, Craig Feinstein <cafei...@msn.com> wrote:
>
> > > [...]
> > > In our real world, it is a known fact that 3+4=7. But how can we be
> > > sure that there are no invisible pixies running around taking balls
> > > away from us causing us to think that 3+4=7 when really 3+4=8?

>
> > > My point is that mathematics is considered a deductive science, in
> > > which everything is absolutely certain. But how can mathematics prove
> > > that the above scenario cannot be true?

>
> > I don't think mathematics is a deductive science: mathematics is
> > hardly a science at all. OTOH, in a world were 3+4=7, I'd also expect
> > 1=/=0: i.e. no mathematical fact exists in isolation...

>
> Thinking: It is logic that grounds mathematics, i.e. it is logic that
> gives mathematics its initial premise and final validation.
>
> -LV

How can that be, if Mathematical Logic is a branch of mathematics ?
It is NOT logic that grounds mathematics. It is rather mathematics
that grounds logic. (And physics grounds mathematics, but that is ..
quite another story)

Han de Bruijn

Date Subject Author
1/23/11 Craig Feinstein
1/23/11 master1729
1/23/11 LudovicoVan
1/24/11 LudovicoVan
1/24/11 LudovicoVan
1/24/11 Virgil
1/23/11 Ilmari Karonen
1/23/11 Ilmari Karonen
1/23/11 Virgil
1/23/11 Tim Little
1/23/11 Joshua Cranmer
1/24/11 hagman
1/24/11 Joshua Cranmer
1/23/11 Brian Chandler
1/24/11 donstockbauer@hotmail.com
1/24/11 cwldoc
1/24/11 Craig Feinstein
1/24/11 Joshua Cranmer
1/24/11 Craig Feinstein
1/25/11 Hauke Reddmann
1/29/11 Bill Taylor