Standpoint logics offer unified modal logic-based formalisms for representing multiple heterogeneous viewpoints. At the same time, many non-monotonic reasoning frameworks can be naturally captured using modal logics, in particular using the modal logic S4F. In this work, we propose a novel formalism called S4F Standpoint Logic, which generalises both S4F and standpoint propositional logic and is therefore capable of expressing multi-viewpoint, non-monotonic semantic commitments. We define its syntax and semantics and analyze its computational complexity, obtaining the result that S4F Standpoint Logic is not computationally harder than its constituent logics, whether in monotonic or non-monotonic form. We also outline mechanisms for credulous and sceptical acceptance and illustrate the framework with an example.

翻译：立场逻辑提供了基于模态逻辑的统一形式化框架，用于表示多个异构观点。与此同时，许多非单调推理框架可以自然地通过模态逻辑来刻画，特别是使用模态逻辑S4F。在本研究中，我们提出了一种称为S4F立场逻辑的新形式化框架，该框架同时推广了S4F逻辑和立场命题逻辑，因此能够表达多视角、非单调的语义承诺。我们定义了其语法和语义，并分析了其计算复杂度，得出以下结论：无论采用单调形式还是非单调形式，S4F立场逻辑的计算复杂度均不高于其构成逻辑。我们还概述了轻信接受与怀疑接受的机制，并通过示例对该框架进行了说明。