This non-implication,
Form 77 \( \not \Rightarrow \)
Form 51,
whose code is 6,
is constructed around a proven non-implication as follows:
Hypothesis | Statement |
---|---|
Form 316 | <p> If a linearly ordered set \((A,\le)\) has the fixed point property then \((A,\le)\) is complete. (\((A,\le)\) has the <em>fixed point property</em> if every function \(f:A\to A\) satisfying \((x\le y \Rightarrow f(x)\le f(y))\) has a fixed point, and (\((A,\le)\) is <em>complete</em> if every subset of \(A\) has a least upper bound.) </p> |
Conclusion | Statement |
---|---|
Form 51 | <p> <strong>Cofinality Principle:</strong> Every linear ordering has a cofinal sub well ordering. <a href="/articles/Sierpi\'nski-1918">Sierpi\'nski [1918]</a>, p 117. </p> |
The conclusion Form 77 \( \not \Rightarrow \) Form 51 then follows.
Finally, the
List of models where hypothesis is true and the conclusion is false:
Name | Statement |
---|---|
\(\cal N37\) A variation of Blass' model, \(\cal N28\) | Let \(A=\{a_{i,j}:i\in\omega, j\in\Bbb Z\}\) |