This non-implication, Form 119 \( \not \Rightarrow \) Form 299, whose code is 4, is constructed around a proven non-implication as follows:

  • An (optional) implication of code 1 or code 2 is given. In this case, it's Code 2: 10175, whose string of implications is:
    118 \(\Rightarrow\) 119
  • A proven non-implication whose code is 3. In this case, it's Code 3: 1260, Form 118 \( \not \Rightarrow \) Form 299 whose summary information is:
    Hypothesis Statement
    Form 118 <p> Every linearly orderable topological space is normal.  <a href="/books/28">Birkhoff [1967]</a>, p 241. </p>

    Conclusion Statement
    Form 299 <p> Any extremally disconnected compact Hausdorff space is projective in the category of Boolean topological spaces. </p>

  • This non-implication was constructed without the use of this last code 2/1 implication

The conclusion Form 119 \( \not \Rightarrow \) Form 299 then follows.

Finally, the
List of models where hypothesis is true and the conclusion is false:

Name Statement
\(\cal M1\) Cohen's original model Add a denumerable number of generic reals (subsets of \(\omega\)), \(a_1\), \(a_2\), \(\cdots\), along with the set \(b\) containing them

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