First published in 1973. This book proposes and tests a theory about human memory, about how a person encodes, retains, and retrieves information from memory. The book is especially concerned with memory for sentential materials. We propose a theoretical framework which is adequate for describing comprehension of linguistic materials, for exhibiting the internal representation of propositional materials, for characterizing the interpretative processes which encode this information into memory and make use of it for remembering, for answering questions, recognizing instances of known categories, drawing inferences, and making deductions.