The above painting is by David Friedrich Caspar and is called “Man and Woman Contemplating the Moon.” It was painted between 1830 and 1835.
Priest of Nature: The Religious Worlds of Isaac Newton
By Rob Iliffe
Oxford University Press, 536 pp., $34.95
July 10, 2017
A case can be made that Isaac Newton was the most important man that ever lived. No one would mistake him as the greatest man who ever lived, in the sense of his goodness as a person or as someone with an admirable personality, but he did do more than anyone else to show that the entire universe behaves in a mechanistic manner and is predictable. That insight has had a profound impact on the most fundamental manner in which we live as well as how we perceive of the universe.
Indulge in the fantasy, for a moment, that you are living in the seventeenth century and have a rudimentary understanding of the physical world. One hundred and fifty years ago a monk named Copernicus proposed that the sun, and not the earth, lay at the center of the known universe. The evidence is beginning to mount from the works of Kepler and Galileo that Copernicus was right and that the planets move around the sun in a predictable manner. Galileo has also described mathematically how bodies fall to the surface of the earth. Both the work of Kepler and Galileo were enormous intellectual leaps forward for mankind. But, why was it that objects always fall to the surface of the earth and why is it that planets stay in orbit around the sun and the moon around the earth? The answer to that question may well be the crowning achievement of human thought.
Enter Isaac Newton. Galileo may have already understood inertia – that objects require a force to move a resting object or stop a moving object – but Newton was the first to realize that some kind of force is necessary to change the motion, or accelerate, any object. He then stumbled upon a truly revolutionary insight. What if the force causing an object to fall to the earth and the force causing the motion of celestial bodies to constantly change was the exact same force?
To see if this hypothesis, which at first sounds crazy, could be true consider the moon. As the moon orbits the earth, it is constantly falling, but because the earth is curved it never gets closer to the earth as it falls. How much does the moon fall towards the earth over a period of time, say each second? The answer to that question can actually be found using geometry known to the ancient Greeks.
In the diagram above, if s is the distance the moon falls in a second, then x is the distance it moves horizontally in one second. It takes about twenty-nine days for the moon to completely orbit the earth and observations of eclipses allowed mathematicians to calculate that the distance from the earth to the moon is equal to about thirty times the diameter of the earth, which also was known to be about eight thousand miles. The total circumference of the moon’s orbit is two multiplied by pi multiplied by thirty multiplied by eight-thousand miles. That calculation equals 1,507,964 miles per twenty-nine days, or 2,505,600 seconds. The quantity “x” is then 0.64 miles or 3,380 feet.
The full diameter of the moon’s orbit is twice its radius or 480,000 miles. Since there are two similar triangles in the diagram, we have all that is needed to determine “s,” since the ratio of x to s is equal to the ratio of D-s to x. “S” is equal to .0045 feet or about 1/20th of an inch. That’s how far the moon falls each second.
Galileo had already established the mathematics by which objects fell to the earth before Newton was alive. As an object falls to the earth, the distance it travels is proportional to the square of time, with its position given by the equation of one-half times the gravitational constant times the square of time. Under the influence of gravity, all objects will fall directly towards the center of the earth; after one second it will have fallen by sixteen feet, two seconds by sixty-four feet, etc. Based upon Kepler’s laws of planetary motion, Newton deduced that the effects of gravity must be proportional to the inverse square of the distance between objects. The moon, then, should be attracted to the earth at a strength that is one divided by sixty-squared. Using universal gravitation then, the moon should fall by sixteen feet divided by sixty-squared or 1/20th of an inch.
Newton’s genius extended also to mathematics, where he invented the calculus in order to adequately describe the physical laws he illuminated. Using the concept of a mathematical limit, he was able to solve two problems that had long perplexed mathematicians: how to find the slope of an arbitrary tangent line to a curve and a general method for finding the areas under curves. As it turns out and is recorded as the Fundamental Theorem of Calculus, these two processes are inverses of each other.
What is the point of rehashing these old discoveries by Isaac Newton? In order to fully appreciate Rob Iliffe’s new book Priest of Nature, it is important to understand just how much Isaac Newton meant to science and mathematics. His achievements in these areas probably surpass anyone else who has ever lived. Alexander Pope appropriately said,
“Nature and nature’s laws
Lay hid in night
God said, ‘Let Newton be,’
And all was light.”
Historians of science and of the enlightenment have been well aware for a long time that Newton’s intellect was not solely, or even primarily, directed towards the physical universe. He seemed much more fascinated by subjects like alchemy and the metaphysics of the bible. His views were heretical to the Church of England at the time and have been something of an embarrassment to the scientific establishment since, which may be why no one has examined these viewpoints so exhaustively until Iliffe. The identity of the “whore of Babylon,” the Unitarian origins of the Christian Church, the biblical chronology pointing to the end times, and a general method of converting elements to gold were far more fascinating endeavors to Newton than the law of universal gravitation.
Newton was inculcated with religious teaching from a very young age, as were most children of his time. He would have been taught the fundamental teachings of the Church and been required to memorize various biblical passages. Between 1655 and 1660 (when Newton was between ages twelve and seventeen) he attended the Free Grammar School at Grantham where he excelled. His father died before he was born and his stepfather was a Reverend, whom Newton despised. His schooling gave him an outlet for his unhappy life at home.
Newton’s scientific discoveries were largely in the 1660s and by the 1670s, his notebooks reveal an absorption with the religious doctrine of the Trinity. He believed that the first Christians had no conception of the teaching and that it was only added to Christian teaching in the fourth century. He further believed that Catholic theologians had corrupted the Bible rather than come to terms with this fact.
Among the fascinating sections in Mr. Iliffe’s book is a chapter entitled “Methodising the Apocalypse.” Newton’s proficiency with mathematics and obsession with the Bible made it all but certain that he would turn his attention at some point to the mathematical mysteries of biblical prophecy. At the end of the 1670s, by that point far removed from the twenty-four-year-old man who unlocked the secrets of the heavens, he had developed a sophisticated and original viewpoint on how biblical prophecies had been fulfilled in history. He did not believe the scriptures made literal claims about the physical world, but were instead deeply figurative. He saw the office of the Pope as the biblical Antichrist and calculated based upon that that the world “could” end by the year 2060, although Newton believed it was not possible to affix a precise date to the end of the world.
He interpreted the biblical language of a “remnant” as meaning that only a few people scattered throughout the earth would have the ability to understand the secrets contained within the Bible after centuries of obfuscation and that these men would spread this truth throughout the earth before the end of the world. That was ultimately the driving force behind Newton’s quest: the belief that the once true and pure faith of Christianity had become concealed and hidden to almost all. In that sense, his religious quest was in the same vein as his scientific quest, to unlock the secrets of the universe.
Why has Newton’s religious writings and beliefs not been given much attention until now? Partially it is because they are hard to categorize and still find an audience. They are not scientific and so are discarded by scientists as superfluous. They are eschatological in nature but are so heretical that most movements would turn aside from them.
In reality, Newton’s quest to understand God’s thoughts, can at times seem like a great adventure despite the seriousness and complexity of the work. That’s a tribute to Mr. Iliffe. But, perhaps the greatest thing to come out of the book is an illumination of how Newton saw his scientific advancements. As far back as the Greeks, heliocentric models of the solar system were proposed. Newton saw men like Copernicus leading up to himself as not discovering new truths of the world, but illuminating hidden truths that falsehood had buried. His view of religious truth was identical.
Priest of Nature does a miraculous job of placing Newton’s religious beliefs in the context of both existing Protestant beliefs and Newton’s scientific advances. That is not an easy thing to do and it does so in a way that makes subjects not traditionally enjoyable a true fascination to read.
We ultimately are likely to accept the scientific teachings of Newton and reject his religious writings as the ravings of an unbalanced man. Yet, each one of us confronts some of the same questions that Newton confronted and we often do so with two minds, exploring our surroundings in the language of both the physical and the metaphysical. Science and religion may have moved into two very different disciplines as the centuries have passed but within each heart and mind, they continue to mingle. Four-hundred years later, all of us set off on the same adventure as Isaac Newton.