This non-implication,
Form 134 \( \not \Rightarrow \)
Form 161,
whose code is 6,
is constructed around a proven non-implication as follows:
Hypothesis | Statement |
---|---|
Form 134 | <p> If \(X\) is an infinite \(T_1\) space and \(X^{Y}\) is \(T_5\), then \(Y\) is countable. (\(T_5\) is 'hereditarily \(T_4\)'.) </p> |
Conclusion | Statement |
---|---|
Form 390 | <p> Every infinite set can be partitioned either into two infinite sets or infinitely many sets, each of which has at least two elements. <a href="/excerpts/Ash-1981-1">Ash [1983]</a>. </p> |
The conclusion Form 134 \( \not \Rightarrow \) Form 161 then follows.
Finally, the
List of models where hypothesis is true and the conclusion is false:
Name | Statement |
---|---|
\(\cal N1\) The Basic Fraenkel Model | The set of atoms, \(A\) is denumerable; \(\cal G\) is the group of all permutations on \(A\); and \(S\) isthe set of all finite subsets of \(A\) |