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From: immibis <news@immibis.com>
Newsgroups: comp.theory,sci.logic
Subject: Re: A computable function that reports on the behavior of its actual
 self is not allowed
Date: Mon, 13 May 2024 23:50:56 +0200
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On 13/05/24 15:39, olcott wrote:
> On 5/13/2024 4:34 AM, Fred. Zwarts wrote:
>> Op 12.mei.2024 om 21:27 schreef olcott:
>>> Computable functions are the basic objects of study in computability
>>> theory. Computable functions are the formalized analogue of the
>>> intuitive notion of algorithms, in the sense that a function is
>>> computable if there exists an algorithm that can do the job of the
>>> function, i.e. given an input of the function domain it can return the
>>> corresponding output. https://en.wikipedia.org/wiki/Computable_function
>>>
>>> A computable function that reports on the behavior of its actual
>>> self (or reports on the behavior of its caller) is not allowed.
>>
>> So, olcott uses his authority to create a new problem. Why would 
>> anybody be interested in such limitation?
>>
> 
> The definition of computable function is an axiomatic basis
> not any mere authority.
> 
There's no axiom that says computable functions aren't allowed to have 
themselves as input. If you write a function that tests whether a number 
is prime, you can give its own Gödel number as input to see whether its 
Gödel number is prime. That is not a problem.