关键词: 格值命题逻辑, &alpha, -归结原理, 广义文字, 正规性, 语义性质

Abstract: Lattice-valued propositional logic based on lattice implication algebra can represent incomparability and imprecise. Generalized literal is a core concept of a-resolution principle in this logic system, and it is the basic unit in a-resolution. The normal property of logical formulae is one of important properties in a-resolution automated reasoning for persevering completeness, its semantic properties are characterized by syntactic of logical formulae. In this paper, some normal properties of generalized literals in LP（X） are studied from a semantic view. Concretely, whether the truth values of two traditional types of formulae （i.e., F1 →F2, （F1→F2）'） are normal is discussed. It provides a theoretical foundation for studying the forms of generalized literals and its a-resolution fields.

Key words: lattice-valued propositional logic, α-resolution principle, generalized literal, normal, semantic property