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Elliot Glazer
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No, this principle implies $\mathrm{DC}_{\mathbb{R}}.$ Suppose $T$ is a tree on $\mathbb{R}^{<\omega}$ with no leaves or branches. Let $\mathcal{A}$ consist of all $A \subset \omega \times \omega$ such that for some $\langle r_i: i<n \rangle \in T,$ $$A=\{(2i, j): i < n, j \in r_i\} \cup \{(2i+1, k): i<n, k \not \in r_i\}.$$

Then $\mathcal{A}$ has no infinite chains or maximal elements.

Elliot Glazer
  • 4.6k
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  • 25
  • 43