Re: The simple essence of Proof Theoretic Semantics
Mikko <[email protected]>
| Newsgroups | sci.logic,comp.theory,comp.ai.philosophy,sci.math |
|---|---|
| Organization | A noiseless patient Spider |
| Message-ID | <[email protected]> |
On 04/07/2026 16:32, olcott wrote:
> On 7/4/2026 2:37 AM, Mikko wrote:
>> On 2026-07-02 dbush wrote:
>>
>>> The halting problem doesn't actually have self reference, as
>> > algorithms can be copied as in the below example of algorithm D:
>>>
>>> void D(ptr *I)
>>> {
>>> // algorithm D; input: I
>>> ptr *X = D;
>>> ptr *Y = I;
>>> int result;
>>> {
>>> // algorithm H; inputs: X,Y
>>> result = 0;
>>> }
>>> if (result == 1) {
>>> while (1);
>>> }
>>> }
>>>
>>> Which is the counter example input to algorithm H:
>>>
>>> int H(ptr *X, ptr *Y)
>>> {
>>> int result;
>>> {
>>> // algorithm H; inputs: X,Y
>>> result = 0;
>>> }
>>> return result;
>>> }
>>
>> On 03/07/2026 18:36, olcott wrote:
>>> On 7/3/2026 4:22 AM, Mikko wrote:
>>>> On 02/07/2026 17:51, olcott wrote:
>>>>>
>>>>> Do you know enough about C to understand that
>>>>> dbush example was foolish nonsense when proposed
>>>>> to show the halting problem counter-example?
>>>>
>>>> It is a valid example of a C program. It was present as a part of a
>>>> claim about you, and your response was the false claim that "That
>>>> is just nonsense". Later in the discussion you offer more evidence
>>>> to support his claim.
>>>
>>> His halt decider did not look at its input.
>>
>> For every possible input his H halts and returns either 0 for false
>> or 1 for true. Therefore his H is a decider. It return 0 for D
>> although D halts so the decider H is not a halt decider.
>
> counter-factual H always returns 0.
There is nothing counter-factual in my statement that dbush's H returns
0 for his D. It is a fact, not a hypthesis.
--
Mikko