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Using First-Order Logic to Reason about Policies

Joseph Y. Halpern·Vicky Weissman
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Abstract

A policy describes the conditions under which an action is permitted or forbidden. We show that a fragment of (multi-sorted) first-order logic can be used to represent and reason about policies. Because we use first-order logic, policies have a clear syntax and semantics. We show that further restricting the fragment results in a language that is still quite expressive yet is also tractable. More precisely, questions about entailment, such as `May Alice access the file?', can be answered in time that is a low-order polynomial (indeed, almost linear in some cases), as can questions about the consistency of policy sets.

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Joseph Y. Halpern, Vicky Weissman. 2006-05-15. Using First-Order Logic to Reason about Policies. https://arxiv.org/abs/cs/0601034

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