Re: Indirect Reference Changes the Behavior of DDD() relative to DDD emulated by HHH

Op 31.aug.2024 om 14:50 schreef olcott:

On 8/30/2024 8:31 AM, Mikko wrote:

On 2024-08-29 14:04:05 +0000, olcott said:
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On 8/29/2024 3:00 AM, Mikko wrote:

On 2024-08-28 11:46:58 +0000, olcott said:
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On 8/28/2024 2:33 AM, Mikko wrote:

On 2024-08-27 13:04:26 +0000, olcott said:
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On 8/27/2024 12:45 AM, joes wrote:

Am Mon, 26 Aug 2024 18:03:41 -0500 schrieb olcott:

On 8/26/2024 7:42 AM, Ben Bacarisse wrote:

Mike Terry <news.dead.person.stones@darjeeling.plus.com> writes:

On 23/08/2024 22:07, Ben Bacarisse wrote:

>

We don't really know what context Sipser was given.  I got in touch
at the time so I do know he had enough context to know that PO's
ideas were "wacky" and that had agreed to what he considered a "minor
remark". Since PO considers his words finely crafted and key to his
so-called work I think it's clear that Sipser did not take the "minor
remark" he agreed to to mean what PO takes it to mean!  My own take
if that he (Sipser) read it as a general remark about how to
determine some cases, i.e. that D names an input that H can partially
simulate to determine it's halting or otherwise.  We all know or
could construct some such cases.

>
Exactly my reading.  It makes Sipser's agreement natural, because it
is both correct [with sensible interpretation of terms], and moreover
describes an obvious strategy that a partial decider might use that
can decide halting for some specific cases.  No need for Sipser to be
deceptive or misleading here, when the truth suffices.  (In particular
no need to employ "tricksy" vacuous truth get out clauses just to get
PO off his back as some have suggested.)

>
Yes, and it fits with his thinking it a "trivial remark".

>

That aside, it's such an odd way to present an argument: "I managed to
trick X into saying 'yes' to something vague".  In any reasonable
collegiate exchange you'd go back and check: "So even when D is
constructed from H, H can return based on what /would/ happen if H did
not stop simulating so that H(D,D) == false is correct even though D(D)
halts?".  Just imagine what Sipser would say to that!

Is this an accurate phrasing, pete?

>
Deciders never compute the mapping of the computation
that they themselves are contained within.

>
Why not? A decider always either accepts or rejects its input.

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The computation that they themselves are contained within cannot
possibly be an input.

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What would prevent that if the input language permits computations?
>

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When a TM takes its own machine description as input
this is not always that same behavior as the direct
execution of the machine. It is not the same because
it is one level of indirect reference away.

>
Now you contradict what you said above. You said that deciders never
conpute the mapping of the computation they themselves are contained
within.

 Although deciders cannot possibly see their own behavior
other people can see this behavior.
 

Now you are saying that they do in a way that might not be
as expected.
>

 If is a verified fact that DDD has different behavior
before it is aborted in the same way that people are
hungry before they eat.

No, the behaviour specified by the finite string does not change when a simulator decides to do the simulation only halfway. It is just an incorrect simulation.

 than the behavior of DDD after it has been aborted,
people are not hungry after they eat.

If two people are hungry and one of them eats, the other one is still hungry and needs to eat. It is stupid to say that they are no longer hungry because they have eaten.
Similarly the simulating HHH is not longer hungry, but the simulated HHH still is hungry and has not yet eaten.

 The direct execution of DDD includes the behavior
of the emulated DDD after it has been aborted.

And the simulator should also simulate until it sees the behaviour of after the simulated HHH has aborted its simulator. But, of course, it can't do that.
HHH cannot possibly simulate itself correctly up to the end.
I told you so many times. When will you finally understand it?

 The emulation of DDD includes the behavior of DDD
before it has been aborted.

Which makes it an incomplete simulation, which does not tell anything about how a correct simulation would continue. Any prediction is just a wild guess. An incorrect guess in this case.

 The behavior of infinite recursion is different
before its second recursive call has been aborted
than after this second call has been aborted.

Dreaming again of an infinite recursion? Stop dreaming. HHH is programmed to prevent an infinite recursion. That holds for both the simulating and the simulated HHH.
Dreams are no substitute for facts.
That the simulating HHH fails to see that the simulated HHH would also prevent the infinite recursion, is just a programming error and not a justification for deciding that it sees an infinite recursion.
HHH cannot possibly simulate itself correctly up to the end.