We have the following indirect implication of form equivalence classes:
| Implication | Reference |
|---|---|
| 264 \(\Rightarrow\) 202 |
Variations of Zorn's lemma, principles of cofinality, and Hausdorff's maximal principle, Part I and II, Harper, J. 1976, Notre Dame J. Formal Logic |
| 202 \(\Rightarrow\) 91 | note-75 |
| 91 \(\Rightarrow\) 79 | clear |
| 79 \(\Rightarrow\) 70 | clear |
| 70 \(\Rightarrow\) 142 | The Axiom of Choice, Jech, 1973b, page 7 problem 11 |
Here are the links and statements of the form equivalence classes referenced above:
| Howard-Rubin Number | Statement |
|---|---|
| 264: | \(H(C,P)\): Every connected relation \((X,R)\) contains a \(\subseteq\)-maximal partially ordered set. |
| 202: | \(C(LO,\infty)\): Every linearly ordered family of non-empty sets has a choice function. |
| 91: | \(PW\): The power set of a well ordered set can be well ordered. |
| 79: | \({\Bbb R}\) can be well ordered. Hilbert [1900], p 263. |
| 70: | There is a non-trivial ultrafilter on \(\omega\). Jech [1973b], prob 5.24. |
| 142: | \(\neg PB\): There is a set of reals without the property of Baire. Jech [1973b], p. 7. |
Comment: