The texts that this book brings together attempt to answer the fundamental questions and mechanisms that governed Arab-Muslim civilization. How, from a few tribes living in the desert and whose members were almost all illiterate, did a real scientific and cultural revolution take place? What roles did the new religion and its vehicle, the Arabic language, play in its birth and its influence ? How and why have multiple and diverse populations contributed to its growth? What is questioned here concerns the past but above all the present and the future of the legacy of this civilization which shone for a long time on an immense empire stretching from Spain to the Indus and which was also the leaven of the development of science and Western culture. Civilization whose Core remains intact despite centuries-old aggressions and destruction of inestimable civilizational productions. Freed from the inertia of its own heirs, from the sterile nostalgia, from the denials of one and the other, from the baseless animosities, from the dust of the colonial night, from endogenous conflicts and others, it will undoubtedly be a fundamental key for a true Renaissance of Muslims themselves and a wealth for the modern world which is suffering the full force of a multidimensional crisis due in large part to ignorance and confinement, to ignorance and rejection of the other.