A junior high school level of understanding of logic
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PeteOlcott
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A junior high school level of understanding of logic
It only takes a junior high school level of understanding of this:
Validity and Soundness https://www.iep.utm.edu/val-snd/
A deductive argument is said to be valid if and only if it takes a form that makes it
impossible for the premises to be true and the conclusion nevertheless to be false.
Otherwise, a deductive argument is said to be invalid.
A deductive argument is sound if and only if it is both valid, and all of its premises
are actually true. Otherwise, a deductive argument is unsound.
To verify that this refutes Tarski undefinability by correctly defining
what Tarski "proved" impossible to define:
When we specify that True(x) is the consequences of the subset
of the of conventional formal proofs of mathematical logic having
true premises then True(x) is always defined and never undefinable.
To understand that I am correct one need only know this:
Whenever every element of the set of premises to a formal proof of mathematical
logic is true then provability derives necessarily true consequences.
Validity and Soundness https://www.iep.utm.edu/val-snd/
A deductive argument is said to be valid if and only if it takes a form that makes it
impossible for the premises to be true and the conclusion nevertheless to be false.
Otherwise, a deductive argument is said to be invalid.
A deductive argument is sound if and only if it is both valid, and all of its premises
are actually true. Otherwise, a deductive argument is unsound.
To verify that this refutes Tarski undefinability by correctly defining
what Tarski "proved" impossible to define:
When we specify that True(x) is the consequences of the subset
of the of conventional formal proofs of mathematical logic having
true premises then True(x) is always defined and never undefinable.
To understand that I am correct one need only know this:
Whenever every element of the set of premises to a formal proof of mathematical
logic is true then provability derives necessarily true consequences.
- Speakpigeon
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Re: A junior high school level of understanding of logic
Your definition seems circular. Could you give an example?PeteOlcott wrote: ↑Wed May 22, 2019 4:28 pm It only takes a junior high school level of understanding of this:
Validity and Soundness https://www.iep.utm.edu/val-snd/
A deductive argument is said to be valid if and only if it takes a form that makes it
impossible for the premises to be true and the conclusion nevertheless to be false.
Otherwise, a deductive argument is said to be invalid.
A deductive argument is sound if and only if it is both valid, and all of its premises
are actually true. Otherwise, a deductive argument is unsound.
To verify that this refutes Tarski undefinability by correctly defining
what Tarski "proved" impossible to define:
When we specify that True(x) is the consequences of the subset
of the of conventional formal proofs of mathematical logic having
true premises then True(x) is always defined and never undefinable.
I don't understand how "provability" could "derive" anything.PeteOlcott wrote: ↑Wed May 22, 2019 4:28 pm To understand that I am correct one need only know this:
Whenever every element of the set of premises to a formal proof of mathematical
logic is true then provability derives necessarily true consequences.
I think you need to look at the way you express your ideas.
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PeteOlcott
- Posts: 1597
- Joined: Mon Jul 25, 2016 6:55 pm
Re: A junior high school level of understanding of logic
Premise(A) All dogs are mammals.Speakpigeon wrote: ↑Wed May 22, 2019 5:32 pmYour definition seems circular. Could you give an example?PeteOlcott wrote: ↑Wed May 22, 2019 4:28 pm It only takes a junior high school level of understanding of this:
Validity and Soundness https://www.iep.utm.edu/val-snd/
A deductive argument is said to be valid if and only if it takes a form that makes it
impossible for the premises to be true and the conclusion nevertheless to be false.
Otherwise, a deductive argument is said to be invalid.
A deductive argument is sound if and only if it is both valid, and all of its premises
are actually true. Otherwise, a deductive argument is unsound.
To verify that this refutes Tarski undefinability by correctly defining
what Tarski "proved" impossible to define:
When we specify that True(x) is the consequences of the subset
of the of conventional formal proofs of mathematical logic having
true premises then True(x) is always defined and never undefinable.
I don't understand how "provability" could "derive" anything.PeteOlcott wrote: ↑Wed May 22, 2019 4:28 pm To understand that I am correct one need only know this:
Whenever every element of the set of premises to a formal proof of mathematical
logic is true then provability derives necessarily true consequences.
I think you need to look at the way you express your ideas.
Premise(B) All mammals breathe.
Conclusion(C) All dogs breathe.
A
B
{A, B} ⊢ C
-------------
∴ C
- Speakpigeon
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- Location: Paris, France, EU
Re: A junior high school level of understanding of logic
So, what is "true" and what is "True(x)" in your example?PeteOlcott wrote: ↑Wed May 22, 2019 6:28 pmPremise(A) All dogs are mammals.Speakpigeon wrote: ↑Wed May 22, 2019 5:32 pmYour definition seems circular. Could you give an example?PeteOlcott wrote: ↑Wed May 22, 2019 4:28 pm It only takes a junior high school level of understanding of this:
Validity and Soundness https://www.iep.utm.edu/val-snd/
A deductive argument is said to be valid if and only if it takes a form that makes it
impossible for the premises to be true and the conclusion nevertheless to be false.
Otherwise, a deductive argument is said to be invalid.
A deductive argument is sound if and only if it is both valid, and all of its premises
are actually true. Otherwise, a deductive argument is unsound.
To verify that this refutes Tarski undefinability by correctly defining
what Tarski "proved" impossible to define:
When we specify that True(x) is the consequences of the subset
of the of conventional formal proofs of mathematical logic having
true premises then True(x) is always defined and never undefinable.
I don't understand how "provability" could "derive" anything.PeteOlcott wrote: ↑Wed May 22, 2019 4:28 pm To understand that I am correct one need only know this:
Whenever every element of the set of premises to a formal proof of mathematical
logic is true then provability derives necessarily true consequences.
I think you need to look at the way you express your ideas.
Premise(B) All mammals breathe.
Conclusion(C) All dogs breathe.
A
B
{A, B} ⊢ C
-------------
∴ C
EB
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PeteOlcott
- Posts: 1597
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Re: A junior high school level of understanding of logic
To keep it as simple as possible we can assume the propositional logic notion of true.Speakpigeon wrote: ↑Thu May 23, 2019 8:18 amSo, what is "true" and what is "True(x)" in your example?PeteOlcott wrote: ↑Wed May 22, 2019 6:28 pmPremise(A) All dogs are mammals.Speakpigeon wrote: ↑Wed May 22, 2019 5:32 pm
Your definition seems circular. Could you give an example?
I don't understand how "provability" could "derive" anything.
I think you need to look at the way you express your ideas.
Premise(B) All mammals breathe.
Conclusion(C) All dogs breathe.
A
B
{A, B} ⊢ C
-------------
∴ C
EB
Every propositional variable without a negation symbol asserts its own truth.
- Speakpigeon
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Re: A junior high school level of understanding of logic
Sure. And?PeteOlcott wrote: ↑Thu May 23, 2019 4:49 pmTo keep it as simple as possible we can assume the propositional logic notion of true.Speakpigeon wrote: ↑Thu May 23, 2019 8:18 amSo, what is "true" and what is "True(x)" in your example?PeteOlcott wrote: ↑Wed May 22, 2019 6:28 pm
Premise(A) All dogs are mammals.
Premise(B) All mammals breathe.
Conclusion(C) All dogs breathe.
A
B
{A, B} ⊢ C
-------------
∴ C
EB
Every propositional variable without a negation symbol asserts its own truth.
EB
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Univalence
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Re: A junior high school level of understanding of logic
That's not simple. That's ambiguous. You clearly stated that Untrue(x) does NOT mean Boolean False.PeteOlcott wrote: ↑Thu May 23, 2019 4:49 pm To keep it as simple as possible we can assume the propositional logic notion of true.
Every propositional variable without a negation symbol asserts its own truth.
So any particular proposition in your grammar could be True, False or Untrue.
Why not Unfalse also?
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PeteOlcott
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Re: A junior high school level of understanding of logic
I am trying to simplify what I am saying enough so that someone that does not totallySpeakpigeon wrote: ↑Thu May 23, 2019 8:18 amSo, what is "true" and what is "True(x)" in your example?PeteOlcott wrote: ↑Wed May 22, 2019 6:28 pmPremise(A) All dogs are mammals.Speakpigeon wrote: ↑Wed May 22, 2019 5:32 pm
Your definition seems circular. Could you give an example?
I don't understand how "provability" could "derive" anything.
I think you need to look at the way you express your ideas.
Premise(B) All mammals breathe.
Conclusion(C) All dogs breathe.
A
B
{A, B} ⊢ C
-------------
∴ C
EB
understand formal proofs of mathematical logic can get the gist of what I am saying.
To really fully understand what I am requires totally understanding formal proofs
of mathematical logic as operations on finite strings.
https://en.wikipedia.org/wiki/Formalism ... thematics)
In foundations of mathematics, philosophy of mathematics, and philosophy of logic,
formalism is a theory that holds that statements of mathematics and logic can be
considered to be statements about the consequences of the manipulation of strings
(alphanumeric sequences of symbols, usually as equations) using established manipulation
rules.
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PeteOlcott
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- Joined: Mon Jul 25, 2016 6:55 pm
Re: A junior high school level of understanding of logic
In other words it is a tautology that sound deduction wouldUnivalence wrote: ↑Thu May 23, 2019 5:22 pmThat's not simple. That's ambiguous. You clearly stated that Untrue(x) does NOT mean Boolean False.PeteOlcott wrote: ↑Thu May 23, 2019 4:49 pm To keep it as simple as possible we can assume the propositional logic notion of true.
Every propositional variable without a negation symbol asserts its own truth.
So any particular proposition in your grammar could be True, False or Untrue.
Why not Unfalse also?
partition the exhaustively complete set of finite strings
(or expressions of language) into True(x) and ¬True(x).
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Univalence
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Re: A junior high school level of understanding of logic
OK so, two categories?PeteOlcott wrote: ↑Thu May 23, 2019 6:40 pm In other words it is a tautology that sound deduction would
partition the exhaustively complete set of finite strings
(or expressions of language) into True(x) and ¬True(x).
Is there any particular reason you are using the syntax ¬True(x) instead of False(x)?
(I have to check with you after you defined 'truth' as an integer and then you initialized it as -1)
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PeteOlcott
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- Joined: Mon Jul 25, 2016 6:55 pm
Re: A junior high school level of understanding of logic
True(x) selects the consequences of the subset of the of conventional formal proofsUnivalence wrote: ↑Thu May 23, 2019 6:42 pmOK so, two categories?PeteOlcott wrote: ↑Thu May 23, 2019 6:40 pm In other words it is a tautology that sound deduction would
partition the exhaustively complete set of finite strings
(or expressions of language) into True(x) and ¬True(x).
Is there any particular reason you are using the syntax ¬True(x) instead of False(x)?
of mathematical logic having true premises.
When operating on the infinite set of finite strings everything else is (exactly one of)
(a) False
(b) Syntactically ill-formed
(c) Semantically ill-formed
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Univalence
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Re: A junior high school level of understanding of logic
*SIGH*PeteOlcott wrote: ↑Thu May 23, 2019 6:45 pm True(x) selects the consequences of the subset of the of conventional formal proofs
of mathematical logic having true premises.
When operating on the infinite set of finite strings everything else is (exactly one of)
(a) False
(b) Syntactically ill-formed
(c) Semantically ill-formed
So any particular string can be classified into 4 separate categories then?
I was joking when I said True, False, Untrue and Unfalse. But you were serious.
Still. Your decision-space is 2 bits. 4 categories.
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PeteOlcott
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Re: A junior high school level of understanding of logic
What can I say, that is the way that truth really works and only truth itself has the authority to specify how itself works.Univalence wrote: ↑Thu May 23, 2019 6:50 pm*SIGH*PeteOlcott wrote: ↑Thu May 23, 2019 6:45 pm True(x) selects the consequences of the subset of the of conventional formal proofs
of mathematical logic having true premises.
When operating on the infinite set of finite strings everything else is (exactly one of)
(a) False
(b) Syntactically ill-formed
(c) Semantically ill-formed
So any particular string can be classified into 4 separate categories then?
I was joking when I said True, False, Untrue and Unfalse. But you were serious.
Still. Your decision-space is 2 bits. 4 categories.
w8094t24589y is (b)
"This sentence is not true" is self-contradictory thus (c)
"2 + 3 = 7" is (a)
This is two actual pages from Tarski's actual proof that says the inability to prove the Liar Paradox proves that True(x) is incomplete:
http://liarparadox.org/247_248.pdf
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Univalence
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Re: A junior high school level of understanding of logic
Tarski doesn't use a 4-value logic.PeteOlcott wrote: ↑Thu May 23, 2019 7:20 pm This is two actual pages from Tarski's actual proof that says the inability to prove the Liar Paradox proves that True(x) is incomplete:
http://liarparadox.org/247_248.pdf
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PeteOlcott
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Re: A junior high school level of understanding of logic
I know hardly anyone does. 4-value logic assumes the mathematical formalist approachUnivalence wrote: ↑Thu May 23, 2019 7:38 pmTarski doesn't use a 4-value logic.PeteOlcott wrote: ↑Thu May 23, 2019 7:20 pm This is two actual pages from Tarski's actual proof that says the inability to prove the Liar Paradox proves that True(x) is incomplete:
http://liarparadox.org/247_248.pdf
of considering everything a finite string instead of a WFF. If we assume that everything
has already been vetted as a WFF conventionally this is only two values of True and False
because everyone totally ignores the case of semantically incorrect WFF.
When we feed a self-contradictory WFF to Tarski's True(x), it cannot "decide" whether
or not the self-contradictory WFF is true or false. No one ever bothered to consider that
a self-contradictory expressions would be neither true nor false because they totally
ignore semantic error.