Newton’s Belief in Spirits May Have Led to the Theory of GravityGregWednesday, September 26th4 Comments2 min read For those who would like to see irrationalism and magical thinking stamped out (*cough* Dawkins *cough*), here’s a prime example of how silly black/white us vs them thinking is: Isaac Newton’s theory of gravity may have arisen from his interest in the spirit world [Newton’] belief in spirits and what the alchemists called active principles almost certainly allowed him to conceive gravity in the mathematical form that we still use today. In Newton’s time, the natural philosophers had turned their backs on astrology and with it, the idea that influences could simply leap across empty space. Instead impulses had to be transmitted through things touching one another. So, if there was a force coming from the Sun that moved the planets, then it had to do so through a medium. Perhaps it was a fluid, driven to circulate by the rotation of the sun, which carried the planets around. This was the thinking of French philosopher René Descartes. Yet Newton could not make the mechanical solution of Descartes work. The vortices simply could not reproduce the changes in speed of the planets as they approached the sun. Alchemy offered a way out by having as a philosophical underpinning that non-material influences – spirits – existed. These needed no physical contact and could induce transformations or movement through the triggering of “active principles” within an object. Primed to believe in these ideas, Newton discovered a simple, elegant mathematical equation that described the behaviour of gravity without the need for an intervening fluid. Gravity apparently worked across empty space. He called this principle “action at a distance” and instead of “spirit” began using the word “force” to better reflect its mathematical character. His equation also reveals the “active principle” that governs an object’s response to gravity. It is mass. With such direct analogies to spirits and active principles, Newton must surely have felt some sort of vindication for his alchemical beliefs. The theory of gravity was so successful that it became one of the triggers for the Age of Enlightenment. Although hardly anyone now believes in the concept of alchemy, we do still believe that gravity can exert an influence across empty space. Engineers still use Newton’s maths to launch satellites and send spacecraft to distant planets. So was Sir Isaac a scientist or a sorcerer? In truth, he was a bit of both. And that was why he could succeed where others had failed. I find it rather amusing that Richard Dawkins is a fan of the poetry of W.B. Yeats, considering the latter’s inspiration in mysticism and occultism. Dawkins famously brushed that complication aside by saying “oh Yeats wrote a lot of pretty words; whether they mean anything is another matter.” That’s not as easily done when it comes to Newton I’d imagine… BBC: Was Newton a Scientist or a Sorcerer?