Editing 2610: Assigning Numbers

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This allowed Gödel to make the statement "This statement cannot be proven based on the axioms provided" in a mathematically rigorous way. A simple proof by contradiction shows that the statement cannot be false, and therefore (in most logical systems) must be true. The proof goes as follows: 1. Assume that "This statement cannot be proven from the axioms" (Call this statement G) is false.<ref>Call this assumption A.</ref> 2. Therefore G can be proven from the axioms.<ref>Because the negation of the negation is an affirmation.  Based only on A.</ref> 3. The axioms exist.<ref>Call this assumption B</ref> 4. Therefore, G is true.<ref>via {{w|Modus ponens}} applied to 2 and 3, based on A and B</ref> 5. Therefore, G and also not G.<ref>via {{w|Conjunction introduction}} applied to 1 and 4, based on A and B</ref> 6.  This is a contradiction, and therefore A (that is, 'not G') or B (ZFC) must be wrong. We are not willing to sacrifice assumption B, so we must conclude that A is false, given B.<ref>{{w|Reductio ad absurdum}} applied to 1,3, and 5</ref> 7.  Therefore, G.
 
This allowed Gödel to make the statement "This statement cannot be proven based on the axioms provided" in a mathematically rigorous way. A simple proof by contradiction shows that the statement cannot be false, and therefore (in most logical systems) must be true. The proof goes as follows: 1. Assume that "This statement cannot be proven from the axioms" (Call this statement G) is false.<ref>Call this assumption A.</ref> 2. Therefore G can be proven from the axioms.<ref>Because the negation of the negation is an affirmation.  Based only on A.</ref> 3. The axioms exist.<ref>Call this assumption B</ref> 4. Therefore, G is true.<ref>via {{w|Modus ponens}} applied to 2 and 3, based on A and B</ref> 5. Therefore, G and also not G.<ref>via {{w|Conjunction introduction}} applied to 1 and 4, based on A and B</ref> 6.  This is a contradiction, and therefore A (that is, 'not G') or B (ZFC) must be wrong. We are not willing to sacrifice assumption B, so we must conclude that A is false, given B.<ref>{{w|Reductio ad absurdum}} applied to 1,3, and 5</ref> 7.  Therefore, G.
 
===Explanatory footnotes for the above===
 
<references />
 
  
 
Notice that the truth of Gödel's statement does not depend on any particular set of axioms, and adding axioms (such as "Gödel's particular statement is true") only opens up new iterations of the statement which cannot be proven based on the expanded set of axioms (A statement such as "All statements of a similar nature to Gödel's particular statement" is not precise enough to serve as an axiom.).  As such, with a little more legwork, it can be proven that any logical system robust enough to accommodate arithmetic must necessarily contain facts that are true within the system but cannot be proven or disproven within the system.  The importance of this result cannot be understated, as it upended the entire philosophy of mathematics.  {{w|David Hilbert}}'s famous proclamation "We must know, we will know" is simply incorrect. ... Either that, or (ironically) Gödel used an "inconsistent" or "incomplete" system to produce his result.
 
Notice that the truth of Gödel's statement does not depend on any particular set of axioms, and adding axioms (such as "Gödel's particular statement is true") only opens up new iterations of the statement which cannot be proven based on the expanded set of axioms (A statement such as "All statements of a similar nature to Gödel's particular statement" is not precise enough to serve as an axiom.).  As such, with a little more legwork, it can be proven that any logical system robust enough to accommodate arithmetic must necessarily contain facts that are true within the system but cannot be proven or disproven within the system.  The importance of this result cannot be understated, as it upended the entire philosophy of mathematics.  {{w|David Hilbert}}'s famous proclamation "We must know, we will know" is simply incorrect. ... Either that, or (ironically) Gödel used an "inconsistent" or "incomplete" system to produce his result.

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