On Sun, Apr 23, 2017 at 7:30 AM, Bruno Marchal <[email protected]> wrote:
>> >> >> Suppose just for >> t >> he sake of argument that non-physical computations did not exist, how >> would our physical world be different? > > > > > It would like if the number 2 does not exist. > No it would not because if non-physical computations did not exist then one physical rock and another physical rock would STILL have the same effect on the physical universe as 2 physical rocks do.. > > > Computation and "universal machine" are non physical notions, > Notions require intelligence and intelligence requires matter that obeys the laws of physics. > > > discovered independently by mathematicians > And mathematicians , just like everybody else, are made of matter that obeys the laws of physics. > t > he fact that the physical reality can implement computations might suggest > already that the physical reality might emerge from computations. > If the non-physical number manipulation 1+1=2 exists then the non-physical number manipulation 1+1=3 exists too. Physics can tell one from of manipulation from the other because in the physical world one rock and another rock will never behave like 3 rocks. How can pure mathematics do the same thing? You can talk about Robinson arithmetic all you want but there are a infinite number of ways numbers can be manipulated in pure mathematics and Robinson arithmetic is just one of those ways. But there is one and only one way numbers can be manipulated that is consistent with the physical world, and we call that one way of manipulation a " calculation " . John K Clark -- 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 post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
