This book is the result of nearly fifty years of study and meditation upon philosophy and philosophical issues as seen in light of the realities revealed through prophecy both objective and inward in the form of illumination. In a world in which philosophy has become so divorced from revealed realities and secular thought has sought to marginalize and even annihilate knowledge imbued with the sacred, it is necessary to return, whenever possible, to the theme of the relation between philosophy and prophecy through different perspectives and angles of vision. Years ago we dealt with the heart of the question of the relation between knowledge and the reality of the sacred in Knowledge ad the Sacred and have returned to this subject from other angles of vision in later works such as The Need for a Sacred Science. In the present work we turn our gaze specifically upon philosophy and especially Islamic philosophy. We deal with over a millennium of Islamic philosophy, its doctrines, history, and approaches, from the angle of vision of the relation between that long philosophical tradition and the realities of prophecy that have always dominated the horizon of the Islamic cosmos and the intellectual climate and space of the Islamic people. Some of the chapters of this book were written as essays over the years. They have all been thoroughly revised and integrated into the framework of this book. Many other chapters are new and were written specifically as integral parts of the present work in order to complete the picture that we have sought to depict in the pages that follow.