" As modern science emerged, it did not banish the concept of occult forces; rather, it accommodated and formalized those that seemed useful, such as magnetism and gravity, relegating others--ghosts, telepathy, telekinesis, and so on--to a ragbag of outmoded notions that, in retaining the label "occult," gradually rendered the word disreputable. But without this belief in the occult, science would have been stymied. Before Renaissance magic stimulated a new interest in the occult, the forces of nature were dismissed as beyond man's capacity to understand. To Thomas Aquinas, magnetism is an "occult virtue which man is not capable of explaining. "

― Philip Ball , The Devil's Doctor: Paracelsus and the World of Renaissance Magic and Science