According to the Sufis, human faculties, although perceptive, are limited: like a radio set, which can receive only certain electromagnetic waves and not other parts of this band. The inability to transcend the barrier of limited senses explains human subjectivity. The Sufis assert that through familiarization with concepts, patterns of thought, and ideas that form part of their contemporary literature, one can learn to penetrate beyond this apparent reality.In Letters and Lectures, the reader will become familiar with the Sufi teaching story and with some of the questions and answers exchanged between the Sufi teacher and his students.