
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

