Axiom Of Choice

We have the following indirect implication of form equivalence classes:

384 \(\Rightarrow\) 62 given by the following sequence of implications, with a reference to its direct proof:

Implication	Reference
384 \(\Rightarrow\) 14	"Maximal filters, continuity and choice principles", Herrlich, H. 1997, Quaestiones Math.
14 \(\Rightarrow\) 107
107 \(\Rightarrow\) 62	clear

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

Howard-Rubin Number	Statement
384:	Closed Filter Extendability for \(T_1\) Spaces: Every closed filter in a \(T_1\) topological space can be extended to a maximal closed filter.
14:	BPI: Every Boolean algebra has a prime ideal.
107:	M. Hall's Theorem: Let \(\{S(\alpha): \alpha\in A\}\) be a collection of finite subsets (of a set \(X\)) then if () for each finite \(F \subseteq A\) there is an injective choice function on \(F\) then there is an injective choice function on \(A\). (That is, a 1-1 function \(f\) such that \((\forall\alpha\in A)(f(\alpha)\in S(\alpha))\).) (According to a theorem of P. Hall (\(\)) is equivalent to \(\left \|\bigcup_{\alpha\in F} S(\alpha)\right\|\ge \|F\|\). P. Hall's theorem does not require the axiom of choice.)
62:	\(C(\infty,< \aleph_{0})\): Every set of non-empty finite sets has a choice function.

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