Guest Author - Lea Terry

Isaac Newton (Jan. 4, 1643 - March 31, 1727)

One of the founders of classical physics, and one of the greatest known scientists of all time, Isaac Newton dabbled in everything from math to astronomy to alchemy to religion. He developed laws that formed the basis of classical mechanics, and his work helped shape our view of both the physical world and what we saw in the heavens.

Born prematurely, Newton was not expected to live. His family were wealthy farmers; his father died three months before his birth, and when he was three, his mother remarried and left him in the care of his maternal grandmother. He did well in school, and in June 1661 was admitted to Trinity College, Cambridge, which focused heavily on the teachings of philosophers like Aristotle. However, Newton’s interests lie in the sciences, with the work of astronomers such as Galileo Galilei, Nicolaus Copernicus and Johannes Kepler. By 1665 he was working on his own mathematical theory, which would later become the calculus. Soon after Newton received his degree in 1665, the university closed down because of the Plague, and Newton returned home, where he continued to work, concentrating on the calculus, optics and gravitation.

It was here that Newton make a theoretical breakthrough that changed science, in his theory of universal gravitation. The long-told story behind this theory is that Newton witnessed an apple fall from a tree, and began contemplating why the apple, and any falling object, always fell downward, instead of veering off to the side or even ascending toward the sky. He theorized that the force that pulled objects toward the center of the Earth was the very same thing that held the Moon in orbit around the Earth; thus, he connected what people saw around them with the mysterious movements of the planets and other celestial bodies.

Newton’s lifelong passion for astronomy is evident in much of his mathematical work, with several of his findings shedding light on the behavior of celestial objects. His book, Philosophiae naturalis principia mathematica, usually just called the Principia, published in 1687, was written at the urging of astronomer Edmund Halley, who urged Newton to publish his work and his applications to astronomy. The Principia is widely regarded the greatest scientific work ever written, and analyzed the behavior of bodies in motion. In it, Newton explained why the planets were attracted to the Sun, and he stated that all heavenly bodies were attracted to each other. He explained a number of other astronomical phenomena, including the orbits of comets, the precession of Earth’s axis, and the impact of the Sun’s gravity on the movement of the Moon.

The Principia brought Newton worldwide recognition and admiration, and he held several high-profile positions throughout his career, including president of the Royal Society, a post he was first elected to in 1703, and to which he was re-elected every year until his death. In 1705, he became the first scientist to be knighted. However, his later years were also fraught with illness and distress. It has been suggested that he suffered from depression throughout his life, and after his second nervous breakdown in 1693, he retired from research. He was also embroiled in a controversy with fellow mathematician Leibnitz over who invented the calculus. He was known for having a temper, often flying into a rage when criticized, and was feared even by his own assistant. He never married and had no children, and divided his estate among his eight half-nieces and half-nephews. After his death, massive amounts of mercury were discovered in his body, perhaps from his alchemy experiments, and it has been speculated that mercury poisoning was the cause of much of his odd behavior in his later years.