Proving Theorems from Reflection

  • Philip D. WelchEmail author
Part of the Synthese Library book series (SYLI, volume 407)


We review some fundamental questions concerning the real line of mathematical analysis, which, like the Continuum Hypothesis, are also independent of the axioms of set theory, but are of a less ‘problematic’ nature, as they can be solved by adopting the right axiomatic framework. We contend that any foundations for mathematics should be able to simply formulate such questions as well as to raise at least the theoretical hope for their resolution.

The usual procedure in set theory (as a foundation) is to add so-called strong axioms of infinity to the standard axioms of Zermelo-Fraenkel, but then the question of their justification becomes to some people vexing. We show how the adoption of a view of the universe of sets with classes, together with certain kinds of Global Reflection Principles resolves some of these issues.


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Authors and Affiliations

  1. 1.School of MathematicsUniversity of BristolBristolEngland

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