Isaac Newton

Isaac Newton

The lifelong quest of Kepler, to understand the motions of the planet, to seek a harmony in the heavens culminated thirty-six years after his death in the work of Isaac Newton.

Newton was born on Christmas Day, 1642, so tiny, that, as his mother told him years later, he would have fit into a quart mug. Sickly, feeling abandoned by his parents, quarrelsome, unsociable, a virgin to the day he died, Isaac Newton was perhaps the greatest scientific genius who ever lived.

Even as a young man, he was impatient with insubstantial questions, such as whether light was “a substance or an accident”, or how gravitation could act over an intervening vacuum. He early decided that the conventional Christian belief in the Trinity was a misreading of Scripture. According to his biographer John Maynard Keynes, “he was rather a Judaic Monotheist of the school of Maimonides. He arrived at this conclusion, not on so-to-speak rational or sceptical grounds, but entirely on the interpretation of ancient authority. He was persuaded that the revealed documents gave no support to the Trinitarian doctrines which were due to late falsifications. The revealed God was one God. But this was a dreadful secret, which Newton was at desperate pains to conceal all his life.

I accomplished my discoveries by thinking upon them. Image: © Megan Jorgensen (Elena)

Like Kepler, Newton was not immune to the superstitions of his day and had many encounters with mysticism. Indeed, much of Newton’s intellectual development can be attributed to this tension between rationalism and mysticism. At the Stourbridge Fair in 1663, at age twenty, he purchased a book on astrology, “out of a curiosity to see what there was in it”. He read it until he came to an illustration which he could not understand, because he was ignorant of trigonometry. So he purchased a book on trigonometry, but soon found himself unable to follow the geometrical arguments. So he found a copy of Euclid’s Elements of Geometry, and began to read. Two years later he invented the differential calculus.

As a student Newton was fascinated by light and transfixed by the Sun. He took to the dangerous practice of staring at the Sun’s image in a looking glass:

In a few hours I had brought my eyes to such a pass that I could look upon no bright objects with neither eye, but I saw the Sun before me, so that I durst neither write nor read but to recover the use of my eyes shut my self up in my chamber made dark three days together and used all means to divert my imagination from the Sun. For if I thought upon him I presently saw his picture though I was in the dark.

In 1666, at the age of twenty-three, Isaac Newton was an undergraduate at Cambridge University when an outbreak of plague forced him to spend a year in idleness in the isolated village of Woolsthorpe, where he had been born. He occupied himself by inventing the differential and integral calculus, making fundamental discoveries on the nature of light and laying the foundation for the theory of universal gravitation. The only other year lit it in the history of physics was Einstein’s “Miracle Year” of 1905. When asked how he accomplished his astonishing discoveries, Newton replied unhelpfully, “By thinking upon them”. His work was so significant that his teacher at Cambridge, Isaac Barrow, resigned his chair of mathematics in favor of Newton five years after the young student returned to college.