Surface reasoning is defined to be deduction conducted in the surface language in terms of certain primitive logical relations. The surface language is a spoken or written natural language (in this paper, English), in contrast to a base language or “deep structure sometimes hypothesized to explain natural language phenomena. The primitive logical relations are inclusion, exclusion and overlap between classes of entities. A calculus for surface reasoning is presented. Then a model for reasoning in this calculus is developed. The model is similar to but more general than syllogistic. In this model, reasoning is represented as construction of fragments (subposets) of lattices. Elements of the lattices are expressions denoting classes of individuals. Strategies to streamline the reasoning process are described. Criteria for strategy selection are proposed
