Recent historical research on the Scientific Revolution has focused on the contribution of ideas and practices that no longer belong to the realm of science, such as astrology and alchemy. Many of the most celebrated astronomers were also astrologers. Used as a diagnostic tool in medicine, astrology formed a regular part of the curriculum of medical schools.

Centuries-old practices of magic and alchemy also remained important traditions for natural philosophers. Early modern practitioners of magic strove to understand and control hidden connections they perceived among different elements of the natural world, such as that between a magnet and iron. The idea that objects possessed hidden or “occult” qualities that allowed them to affect other objects was a particularly important legacy of the magical tradition.

Johannes Kepler exemplifies the interaction among these different strands of interest in the natural world. His duties as court mathematician included casting horoscopes for the royal family, and he based his own life on astrological principles. He also wrote at length on cosmic harmonies and explained elliptical motion through ideas about the beautiful music created by the combined motion of the planets. Another example of the interweaving of ideas and beliefs is Sir Isaac Newton, who was both intensely religious and also fascinated by alchemy, whose practitioners believed (among other things) that base metals could be turned into gold.