Differences in discourse type or genre produce various effects upon readers. Recent empirical research on the cognitive processes of discourse comprehension shows that mature human readers utilize cognitive processes called “comprehension control systems”. These develop in a specialized way for each type or genre of discourse. Comprehension control systems for natural language discourse have to be built-in if they are to be as flexible as those of adult human readers, so they must be designed and constructed as such. This is expected to enable the discourse comprehension system to utilize efficiently the fictional information in literary texts without confusing fictional and actual situations.