Re: Ben fails to understand---- correction

On 7/4/2024 9:25 AM, olcott wrote:

On 10/14/2022 7:44 PM, Ben Bacarisse wrote:

Python <python@invalid.org> writes:
>
Olcott (annotated):
>

   If simulating halt decider H correctly simulates its input D until H
   correctly determines that its simulated D would never stop running
>
   [comment: as D halts, the simulation is faulty, Pr. Sipser has been
    fooled by Olcott shell game confusion "pretending to simulate" and
    "correctly simulate"]
>
   unless aborted then H can abort its simulation of D and correctly
   report that D specifies a non-halting sequence of configurations.

>
I don't think that is the shell game.  PO really /has/ an H (it's
trivial to do for this one case) that correctly determines that P(P)
*would* never stop running *unless* aborted.  He knows and accepts that
P(P) actually does stop.  The wrong answer is justified by what would
happen if H (and hence a different P) where not what they actually are.
>

 <MIT Professor Sipser agreed to ONLY these verbatim words 10/13/2022>
     If simulating halt decider H correctly simulates its input D
     until H correctly determines that its simulated D would never
     stop running unless aborted then
      H can abort its simulation of D and correctly report that D
     specifies a non-halting sequence of configurations.
</MIT Professor Sipser agreed to ONLY these verbatim words 10/13/2022>
 It is the case that H must abort its simulation of P to prevent
its own non-termination. The directly executed P(P) benefits
from H already having aborted its simulation of P. P correctly
simulated H cannot reap this benefit proving that it is a different
sequence of configurations than the directly executed P(P).
 

(I've gone back to his previous names what P is Linz's H^.)
>

In other words: "if the simulation were right the answer would be
right".

>
I don't think that's the right paraphrase.  He is saying if P were
different (built from a non-aborting H) H's answer would be the right
one.
>

But the simulation is not right. D actually halts.

>
But H determines (correctly) that D would not halt if it were not
halted.  That much is a truism.

 Thus H(D,D) must abort the simulation of its input to prevent
its own non-termination.
 

What's wrong is to pronounce that
answer as being correct for the D that does, in fact, stop.
>

 

*REPLACED PARAGRAPH*
The directly executed D(D) is executed in a different memory
process. D correctly simulated by H is simulated in its own
separate memory process. The executed D(D) only halts because
D correctly simulated by H was aborted.
A simpler example is show below so that one is not overwhelmed
with too much detail.

 They are not the same instance of D.
 void DDD()
{
   HHH(DDD); // creates new process context
}           // thus not the same DDD as the
             // one that is directly executed.
int main()
{
   DDD(DDD);
}
 _DDD()
[00002163] 55         push ebp
[00002164] 8bec       mov ebp,esp
[00002166] 6863210000 push 00002163
[0000216b] e853f4ffff call 000015c3
[00002170] 83c404     add esp,+04
[00002173] 5d         pop ebp
[00002174] c3         ret
Size in bytes:(0018) [00002174]
 _main()
[00002183] 55         push ebp
[00002184] 8bec       mov ebp,esp
[00002186] 6863210000 push 00002163 ; push DDD
[0000218b] e8d3ffffff call 00002163 ; call DDD(DDD)
[00002190] 83c404     add esp,+04
[00002193] 33c0       xor eax,eax
[00002195] 5d         pop ebp
[00002196] c3         ret
Size in bytes:(0020) [00002196]
   machine   stack     stack     machine    assembly
  address   address   data      code       language
  ========  ========  ========  =========  =============
[00002183][001037dd][00000000] 55         push ebp      ; housekeeping
[00002184][001037dd][00000000] 8bec       mov ebp,esp   ; housekeeping
[00002186][001037d9][00002163] 6863210000 push 00002163 ; push DDD
[0000218b][001037d5][00002190] e8d3ffffff call 00002163 ; call HHH(DDD)
[00002163][001037d1][001037dd] 55         push ebp      ; housekeeping
[00002164][001037d1][001037dd] 8bec       mov ebp,esp   ; housekeeping
[00002166][001037cd][00002163] 6863210000 push 00002163 ; push DDD
[0000216b][001037c9][00002170] e853f4ffff call 000015c3 ; call HHH(DDD)
 New slave_stack at:103881 ; Create new process context
Begin Local Halt Decider Simulation   Execution Trace Stored at:113889
[00002163][00113879][0011387d] 55         push ebp      ; housekeeping
[00002164][00113879][0011387d] 8bec       mov ebp,esp   ; housekeeping
[00002166][00113875][00002163] 6863210000 push 00002163 ; push DDD
[0000216b][00113871][00002170] e853f4ffff call 000015c3 ; call HHH(DDD)
 New slave_stack at:14e2a9 ; Create new process context
[00002163][0015e2a1][0015e2a5] 55         push ebp      ; housekeeping
[00002164][0015e2a1][0015e2a5] 8bec       mov ebp,esp   ; housekeeping
[00002166][0015e29d][00002163] 6863210000 push 00002163 ; push DDD
[0000216b][0015e299][00002170] e853f4ffff call 000015c3 ; call HHH(DDD)
Local Halt Decider: Infinite Recursion Detected Simulation Stopped
 [00002170][001037d1][001037dd] 83c404     add esp,+04; executed DDD(DDD)
[00002173][001037d5][00002190] 5d         pop ebp    ; executed DDD(DDD)
[00002174][001037d9][00002163] c3         ret        ; executed DDD(DDD)
[00002190][001037dd][00000000] 83c404     add esp,+04
[00002193][001037dd][00000000] 33c0       xor eax,eax
[00002195][001037e1][00000018] 5d         pop ebp
[00002196][001037e5][00000000] c3         ret
Number of Instructions Executed(10073) == 150 Pages
  

--
Copyright 2024 Olcott "Talent hits a target no one else can hit; Genius
hits a target no one else can see." Arthur Schopenhauer