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On 9/12/2024 3:54 AM, Mikko wrote:And Prolog can not expresz the sort of statement that Tarski is using.On 2024-09-11 12:14:53 +0000, olcott said:When a Prolog Fact is specified that cats are animals
>On 9/11/2024 2:05 AM, Mikko wrote:>On 2024-09-10 13:23:39 +0000, olcott said:>
>>>
They all have negation as failure, the key element
required to reject self-contradictory expressions.
The not operator of Prolog is not a part of Horn clause system. It is
not the same as the not operator of ordinary logic. Therefore one nust
be careful with its use and interpretation.
>
You have not defined what you mean with "reject" and how that relates
to the behaviour of Prolog programs.
>
https://en.wikipedia.org/wiki/Negation_as_failure
The failure to prove X from Facts and Rules
means that X is untrue yet not necessarily false.
>
The failure to prove X or ~X from Facts and Rules
means that X is untrue and unfalse, thus not a
truth bearer.
X may represent a real world claim that is either true or false but
cannot be determined either way with Prolog rules.
>
then we can know by Prolog Facts that cats are animals.
So? Prolog can't handle Tarski statement. Rememver, REJECTING Tarski's statement is just admitting that your system can't handle the statement, as a truth predicate can't reject a statement that is syntactically valid.I have defined this at least 100 times.>x = "this sentence is not true">
if ~True(L,x) & ~True(L,~x) "x is rejected as invalid input"
What connection that has to Prolog?
Anyway, you still have not defined what you mean with "reject" and how
that relates to the behaviour of Prolog programs, and you have not
answered the last question.
>
?- LP = not(true(LP)).
LP = not(true(LP)).
?- unify_with_occurs_check(LP, not(true(LP))).
false.
The last line that returns false rejects LP.
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