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| Newsgroups | comp.theory, comp.ai.philosophy, comp.ai.nat-lang, sci.lang.semantics |
|---|---|
| From | olcott <NoOne@NoWhere.com> |
| Subject | Simply defining Gödel Incompleteness away V19 |
| Date | 2020-07-01 21:18 -0500 |
| Message-ID | <67CdnVYcHadl3mDDnZ2dnUU7-WHNnZ2d@giganews.com> (permalink) |
Cross-posted to 4 groups.
Stanford Encyclopedia of Philosophy
considers this as a reasonable approximation of the Gödel sentence:
https://plato.stanford.edu/entries/goedel-incompleteness/#FirIncTheCom
(G) F ⊢ G_F ↔ ¬Prov_F(⌈G_F⌉)
If we assume a formal system contains Robinson's arithmetic and has its
own provability operator then a proof with arithmetization and a proof
without arithmetization would only vary syntactically and not semantically.
If the two proofs are syntactically different yet semantically identical
then their provability would be logically equivalent.
(a) F ⊢ G_F ↔ ¬Prov_F(⌈G_F⌉)
(b) F ⊢ G_F ↔ (F ⊬ G)
// The formal system of Simple_Arithmetic is defined below
// and has its own provability predicate
You can prove that a true statement is true:
"2 + 3 = 5" ↔ (F ⊬ "2 + 3 = 5")
LHS of ↔ is true. RHS of ⊬ is true. RHS of ↔ is false.
You can prove that a false statement is not true:
"2 + 3 = 9" ↔ (F ⊬ "2 + 3 = 9") LHS of ↔ is false.
RHS of ⊬ is false. RHS of ↔ is true.
Thus there does not exist any WFF G of any formal system F that is
logically equivalent to it own unprovability because this is
self-contradictory.
This exact same reasoning applies to (a) because (a) and (b) only vary
syntactically and not semantically thus must have logically equivalent
provability.
/****************************************************************************
This is the formal system of Simple_Arithmetic implemented
as a membership algorithm on finite strings matching this
AWK regular expression: /[0-9]+[\+][0-9]+[=][0-9]+/
****************************************************************************/
char AddWithCarry(char D1, char D2, char& Carry)
{
char SUM = ADD_Digit[D1][D2];
if (Carry == '1' && SUM == '9')
{
SUM = '0';
Carry = '1';
}
else if (Carry == '1' && SUM < '9')
{
SUM = ADD_Digit[SUM][Carry];
Carry = ADD_Carry[D1][D2];
}
else // Carry == '0'
Carry = ADD_Carry[D1][D2];
return SUM;
}
std::string Add(std::string& OP1, std::string& OP2)
{
std::string SUM;
char Carry = '0';
for (int N = OP1.length() - 1; N >= 0; N--)
SUM += AddWithCarry(OP1[N], OP2[N], Carry);
if (Carry == '1')
SUM += '1';
std::reverse(SUM.begin(), SUM.end());
return SUM;
}
//
// (Proven && True) || (Unproven && Untrue)
//
bool ProveInput(std::string& OP1,std::string& OP2, std::string& SUM)
{
std::string RESULT;
RESULT = Add(OP1, OP2);
return (RESULT == SUM);
}
--
Copyright 2020 Pete Olcott
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Simply defining Gödel Incompleteness away V19 olcott <NoOne@NoWhere.com> - 2020-07-01 21:18 -0500
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