We consider relational semantics (R-models) for the Lambek calculus extended with intersection and explicit constants for zero and unit. For its variant without constants and a restriction which disallows empty antecedents, Andreka and Mikulas (1994) prove strong completeness. We show that it fails without this restriction, but, on the other hand, prove weak completeness for non-standard interpretation of constants. For the standard interpretation, even weak completeness fails. The weak completeness result extends to an infinitary setting, for so-called iterative divisions (Kleene star under division). We also prove strong completeness results for product-free fragments.
翻译:我们考虑Lambek演算扩展交乘及显式零与单位常量的关系语义(R-模型)。对于其无常量且禁止空前件的变体,Andreka与Mikulas(1994)证明了强完备性。我们证明该性质在无此限制时失效,但另一方面,针对常量的非标准解释证明了弱完备性。对于标准解释,即使弱完备性也不成立。该弱完备性结果可推广至无穷情形,即所谓的迭代除法(除法下的Kleene星)。此外,我们证明了无积片段的强完备性结果。