# Re: Edge.org: 2014 : WHAT SCIENTIFIC IDEA IS READY FOR RETIREMENT? The Computational Metaphor

```On 18 January 2014 17:16, meekerdb <meeke...@verizon.net> wrote:

>  On 1/17/2014 5:40 PM, LizR wrote:
>
>  But apparently the brain has a lot to do with those computations in
>> Platonia, c.f. anesthetic.  Notice that I'm not a disciple of Platonia.
>>
>
>  Me neither, I am agnostic - but within comp it is assumed, so while
> discussing comp we have to assume it (unless we're rejecting comp on that
> basis). But I can see that Platonia makes sense in that 17 does seem to be
> prime idependently of you and me and everyone else, which is (I'm told)
> enough for the whole shebang to come into some sort of existence.
>
>
> I don't think you have to buy the equivalence between (17 is prime) is
> true and (17 is prime) exists.  In fact Bruno always says you only have to
> believe the first for his argument to succeed.  But then he slips in the UD
> and it seems that every truth of arithmetic implies and existence.  I think
> this is the same problem as step 8.  If everything has to be simulated,
> then there's no difference between simulated and real.  If I'm "really"
> existing in an infinity of world/simulations that are *just like this one
> up to now* - then they ARE this one (c.f. Leibniz).
>
> Well, I haven't managed to get my head around step 8, at least, not if
step 8 is the MGA? (Or maybe I did, if it isn't....)```
```
I suppose what I need to know is how the existence (in any sense) of the
integers and elementary arithmetic operations creates computations. In fact
every possible computation. I believe it's done indexically, whatever that
means ... but I think this is about where I start to feel I shouldn't

If the sheer existence of numbers, + and x implies that all possible
computations "exist "(in an abstract sense) then it all follows - in an
abstract sense. This brings me back to your comment about equivalence (or
not). The thing is, I'd like to know what I'm buying or not buying before I