Hypothesis: HR 43:

\(DC(\omega)\) (DC), Principle of Dependent Choices: If \(S\)  is  a relation on a non-empty set \(A\) and \((\forall x\in A) (\exists y\in A)(x S y)\)  then there is a sequence \(a(0), a(1), a(2), \ldots\) of elements of \(A\) such that \((\forall n\in\omega)(a(n)\mathrel S a(n+1))\).  See Tarski [1948], p 96, Levy [1964], p. 136.

Conclusion: HR 417:

On every non-trivial Banach space there is a non-trivial linear functional (bounded or unbounded).

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

Name Statement

Code: 3

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