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arXiv · 2606.22584

Second order logic and Set Theory Redux

Jouko Väänänen
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Abstract

We argue that second order logic is a weaker form of set theory, despite the fact that the former is formalized in a second order langauge and the latter in a first order language. Along the way, we review the history of interactions between second order logic and set theory, as well as some modern trends.

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Jouko Väänänen. 2026-06-21. Second order logic and Set Theory Redux. https://arxiv.org/abs/2606.22584

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