In this dramatic and entertaining dialogue, Fontenelle explained Cartesian philosophy and cosmology and argued for the existence of life on other worlds. He justified a popular writing style by encouraging women and men to engage in pleasant evening conversation together on scientific topics. According to Fontenelle, “time alone will ruin a world.” As dying Suns turn into comets and carry their surrounding planets with them, civilizations come and go with each passing comet. The History of Science Collections also holds the first edition, published in French in 1686.