For centuries, people have speculated about the possibility that Earth is just an experiment. The ancient Greeks, for example, believed that the gods lived on Mount Olympus and often intervened in human affairs. This idea was later taken up by the Roman poet Virgil, who wrote that the gods "experimented with creating life on Earth." In more recent times, some have suggested that Earth is just a laboratory for ancient astronauts. This theory gained popularity after the publication of Erich von Daniken's 1968 book, Chariots of the Gods. Von Daniken argued that many ancient cultures—including the Egyptians and Mayans—had been visited by aliens, who had given them advanced technologies. While there is no concrete evidence to support this theory, it remains a fascinating possibility.