Paris, 1880. Astronomer Camille Flammarion Suggests Using Science to Unravel the Mysteries of the Universe
Camille Flammarion promoted science through his publications. His seminal 1880 work, Popular Astronomy, was extremely well received by the French middle classes. Flammarion suggested merging science and religion, and he defined Spiritism (the study of the occult) as "the scientific religion."

"For gentlemen," Flammarion claimed, "spiritism is not a religion but a science, a science whose motives we barely know (…). The time of dogma has come to an end. Nature embraces the Universe, and God himself."

At the fin de siècle, science and religion seemed incompatible. In fact, many scientists denied the existence of God and the soul. In contrast, Flammarion proposed a vision that connected science and religion.