Re: The simple essence of Proof Theoretic Semantics

On 06/07/2026 18:27, olcott wrote:
> On 7/6/2026 3:11 AM, Mikko wrote:
>> On 04/07/2026 19:58, olcott wrote:
>>> On 7/4/2026 2:48 AM, Mikko wrote:
>>>> On 04/07/2026 05:37, olcott wrote:
>>>>> On 7/3/2026 9:19 PM, dbush wrote:
>>>>>> On 7/3/2026 10:05 PM, olcott wrote:
>>>>>>> On 7/3/2026 8:58 PM, dbush wrote:
>>>>>>>> On 7/3/2026 9:52 PM, olcott wrote:
>>>>>>>>> On 7/3/2026 5:51 PM, André G. Isaak wrote:
>>>>>>>>>> On 2026-07-03 16:37, olcott wrote:
>>>>>>>>>>> On 7/3/2026 1:47 PM, André G. Isaak wrote:
>>>>>>>>>>>> On 2026-07-03 12:36, olcott wrote:
>>>>>>>>>>>>> On 7/3/2026 1:18 PM, dbush wrote:
>>>>>>>>>>>>
>>>>>>>>>>>>>> If an algorithm takes an input and produces an output, 
>>>>>>>>>>>>>> that is by definition a mapping. 
>>>>>>>>>>>>> That only proves that the definition is incoherent.
>>>>>>>>>>>>> The coherent way that it actually works is that
>>>>>>>>>>>>> inputs are transformed into outputs by applying
>>>>>>>>>>>>> finite string transformation rules to inputs to
>>>>>>>>>>>>> derive outputs.
>>>>>>>>>>>>
>>>>>>>>>>>> Apparently you don't understand the difference between a 
>>>>>>>>>>>> mapping and an algorithm. They are two different things.
>>>>>>>>>>>>
>>>>>>>>>>>> André
>>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> A function that ignores its input and only returns 0
>>>>>>>>>>> is not any sort of halt function.
>>>>>>>>>>
>>>>>>>>>> He was defining 'mapping', not 'halt function'.
>>>>>>>>>>
>>>>>>>>>> André
>>>>>>>>>>
>>>>>>>>>
>>>>>>>>> A actual halt function must compute 
>>>>>>>> The mathematical halting function:
>>>>>>>>
>>>>>>>
>>>>>>> When you actually implement this concretely 
>>>>>>
>>>>>> We find that it is not possible, as Linz and others have proved.
>>>>>
>>>>> Impossible requirements are incorrect requirements.
>>>>
>>>> There is no well known meaning of "incorrect requirements".
>>>
>>> I just established the meaning of incorrect requirements
>>> as any requirement that requires the logically impossible.
>>
>> That is insufficient to make the expression "incorrect requirements"
>> meaningful in Common Language or well known.
> 
> In other words if the requirement is to compute the square
> root of the actual dead flesh of a dead chicken you would
> not reject this out-of hand?

Depends on what yuo count as rejection. I don't think I would
try to meet that requirement.

-- 
Mikko