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arXiv · 2508.05682

Structural Completeness in bi-IPC

Rodrigo Nicolau Almeida·Nick Bezhanishvili
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Abstract

In this note we show that no extension of bi-intuitionistic logic, except for classical logic, is structurally complete; indeed, none of them are passively structurally complete. A direct proof of active structural completeness is given for some simple systems.

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Rodrigo Nicolau Almeida, Nick Bezhanishvili. 2025-08-05. Structural Completeness in bi-IPC. https://arxiv.org/abs/2508.05682

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