Computers, if programed to respond to writer-generated content with heuristic strategies, can guide the writer in the prewriting stage. Heuristics are problem solving strategies that can aid the writer in exploring a topic either through a systematic posting of relevant questions or through an unsystematic process of free-association. To date the only experimental research linking computers and heuristics has been Hugh Burns's "Stimulating Rhetorical Invention in English Composition through Computer-Assisted Instruction," which found that, in a 30-minute period, computer assisted systematic heuristics generated a greater quantity of ideas than traditional unsystematic heuristics. However, the study never determined if the use of computer assisted instruction (CAI) to stimulate rhetorical invention actually helped the writer to write. In a current study, CAI instruction in invention is being compared with traditional classroom invention instruction. The study makes a distinction between systematic and unsystematic heuristics and will look at the quality of the ideas produced by measuring the proportion of ideas used in the actual writing that were produced in the heuristic exercises. This study may show not only that CAI employed during the invention stage helps writers write, but that CAI using systematic heuristics will provide the most beneficial combination. (A list of questions about computers, along with their answers, is appended.) (HOD)