This review essay introduces the work of the Egyptian scientific historian and philosopher Roshdi Rashed, a pioneer in the field of the history of Arab sciences. The article is based on the five volumes he originally wrote in French and later translated into Arabic, which were published by the Centre for Arab Unity Studies and which are now widely acclaimed as a unique effort to unveil the achievements of Arab scientists. The essay reviews this major work, which seems, like Plato’s Republic to have “No Entry for Those Who Have No Knowledge of Mathematics” written on its gate. If you force your way in, even with elementary knowledge of computation, a philosophy will unfold before your eyes, described by the Italian astronomer Galileo Galilei as “written in that great book which ever lies before our eyes—I mean the universe—but we cannot understand it if we do not first learn the language and grasp the symbols, in which it is written. This book is written in the mathematical language, and the symbols are triangles, circles and other geometrical figures, without whose help it is impossible to comprehend a single word of it; without which one wanders in vain through a dark labyrinth.” The essay is a journey through this labyrinth where the history of world mathematics got lost and was chronicled by Rashed in five volumes translated from the French into Arabic. It took him fifteen years to complete.