> On 29 Feb 2020, at 03:45, 'Brent Meeker' via Everything List > <[email protected]> wrote: > > > > On 2/28/2020 5:56 AM, Bruno Marchal wrote: >> >>> On 28 Feb 2020, at 13:05, Philip Thrift <[email protected] >>> <mailto:[email protected]>> wrote: >>> >> >>> >>> Only Platonists jump to a belief that there is a ghostly world of abstract >>> entities called "numbers" that exists outside of matter (whether that >>> matter is your brain or your computer). >> >> We don’t need this either. We need only to believe that 2+3 = 5, or that >> phi_i(j) converges or not converges. The philosophy and metaphysics come >> after. >> If not, it is like studying the working of my brain to convince myself that >> I understand correctly that 2+2=4. That does not work, because my brain >> study is based on my belief that 2+2=4. >> You could aswel say that Einstein’s theory is circular, because you want to >> explain 2+2=4 with Matter, but Einstein’s theory use the numbers, and >> assumes they do what they need to give sense to, say, E= mc^2. >> >> At some point, people have to put *all* the hypothesis on the table, so that >> it is clear what is assumed, and what is derived. > > That doesn't really help because it leaves open the relation between what is > assumed to be true and what is actually.
The whole idea of formalising the theory is to avoid that discussion. If we have some reason to doubt a theory, we discuss with peers, and perhaps we abandon it. But we cannot do the philosophy before the hard work, or we can not progress. The truth of a they is never part of the theory, and since Tarski and Gödel, we know that it has to be like that. > That's why reasoning that is not grounded in ostensive definitions and > empirically tested is just a game. Sure, but that too does not make them true. What the greeks did understood, before Tarski (!à, is that truth is beyond the theory, and requires faith, if only the natural faith that we are not currently doing a nocturnal sort of dream. All this has few incidence on applied physics, but it has already an impact on the foundations of physics, and is of crucial importance when doing metaphysics with the scientific method. There to, an ontological commitment on a notion of reality ((model) for that theory cannot be made. If done in the theory without precaution, that leads to inconsistency. If done with some precaution, it leads to a new different (and more powerful) theory. Bruno > > Brent > > -- > You received this message because you are subscribed to the Google Groups > "Everything List" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected] > <mailto:[email protected]>. > To view this discussion on the web visit > https://groups.google.com/d/msgid/everything-list/72d30f9e-20ec-010c-f5d4-d9c0f45bfcb2%40verizon.net > > <https://groups.google.com/d/msgid/everything-list/72d30f9e-20ec-010c-f5d4-d9c0f45bfcb2%40verizon.net?utm_medium=email&utm_source=footer>. -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/everything-list/92958D98-EC6F-4944-86BE-03C63CE1080F%40ulb.ac.be.
