Axiom Of Choice

We have the following indirect implication of form equivalence classes:

260 \(\Rightarrow\) 322 given by the following sequence of implications, with a reference to its direct proof:

Implication	Reference
260 \(\Rightarrow\) 40	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
40 \(\Rightarrow\) 322	clear

Here are the links and statements of the form equivalence classes referenced above:

Howard-Rubin Number	Statement
260:	\(Z(TR\&C,P)\): If \((X,R)\) is a transitive and connected relation in which every partially ordered subset has an upper bound, then \((X,R)\) has a maximal element.
40:	\(C(WO,\infty)\): Every well orderable set of non-empty sets has a choice function. Moore, G. [1982], p 325.
322:	\(KW(WO,\infty)\), The Kinna-Wagner Selection Principle for a well ordered family of sets: For every well ordered set \(M\) there is a function \(f\) such that for all \(A\in M\), if \(\|A\|>1\) then \(\emptyset\neq f(A)\subsetneq A\). (See Form 15).

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