"Civilizations are born, live, and die, and ours is no exception." If the pagan gods that inspired the construction of Stonehenge, Cheops, and the Parthenon are today relegated to pure mythology, is it reasonable to think that Christianity will be immortal? Studying these ruins makes it possible to think about civilizations and to face with discernment the dynamic of decadence that is imposed after 2,000 years of Judeo-Christianity. Michel Onfray presents here the historical origins of these belief systems. The philosopher details the birth of this common base of values forged by the fathers of the Church, more so than by Jesus, during the first centuries of our era, and who continue to define, in spite of themselves, the identity of our civilization.