Аннотация:
Instantial Neighborhood Logic (INL) employs a two-sorted operator ◻. In INL, formula ◻(α1,…,αj;α0) means, the current point has a neighborhood in which α0 universally holds, and none of α1,…,αj universally fails. In my talk last year at Tbilisi State University, a tableau system for INL was presented. To continue, in this talk we convert that tableau system to a hyper-sequent calculus, and then to a (normal) sequent calculus G3inl. Based on a splitting version of G3inl, we will explain how Lyndon interpolation theorem of INL is constructively established.