Craig Interpolation for Guarded Fragments
arXiv:2304.08086
Abstract
We show that the guarded-negation fragment (GNFO) is, in a precise sense, the smallest extension of the guarded fragment (GFO) with Craig interpolation. In contrast, %we show that the smallest extension of the two-variable fragment (FO2) with Craig interpolation is full first-order logic.
Accepted for presentation at DPFO 2023 workshop