A study was conducted to examine cognitive levels in adults (using Peel's tasks of logical judgment) and to assess their relationship to reading comprehension and various demographic variables. Subsequent to testing their reading comprehension with the California Achievement Test (CAT), forty-one adult education students ranging in age from sixteen to sixty-two were asked to read seven passages adapted from Peel's logical judgment tests and, after each reading, to make a judgment and explain the reasoning. The subjects' responses were rated on each of two dimensions: coordination of information and the data source used. The major findings were (1) concepts of language structure vary in adults, (2) the degree of success on the language concepts measure covaries with reading level for adults in a reading skill development program, (3) good interrater reliability was attained, (4) logical judgment was not related to achievement, (5) results were similar across sex and ethnic groups, (6) differences by age were a peculiarity of the sample, and (7) the factors observed included one which described interrelationships of sex, age, and ethnic status and one each for achievement, language concepts, and local judgments. Given the limitations of the study, adults' performance on the Peel tasks was unrelated to performance on the CAT. (The logical judgment tasks and scoring guidelines are appended.) (EM)