16 Examples of the Madness of Sir Isaac Newton

2. He may have been searching for the philosopher’s stone

During Newton’s lifetime he devoted decades to alchemy, known in his day in England as “chymistry”, much of which was illegal at the time, considered to be heretical. Alchemists sought a material known among them as the philosopher’s stone, a mythical substance believed to be capable of transmuting metals into gold and silver, and to give its possessor eternal life, as well as acting to restore youth and vitality. Alchemists referred to the search for the philosopher’s stone as the “Magnum Opus”, Latin for the Great Work. Because it was heretical and in some respects illegal, alchemists used various linguistic tricks in communicating with each other, including puns and other wordplays as well as outright code, Newton among them.

During Newton’s lifetime, the distinction between science and superstition was vague, and literal interpretation of the Christian Bible was the dominant worldview. As part of his occult studies and alchemy experiments, Newton, besieged by deteriorating mental health, spent much of his time poring over the Book of Revelation in the belief that it contained clues which would lead him to the discoveries which were the goal of the Magnum Opus. He did not publish his works on alchemy during his lifetime, and though some believe that much of his work was destroyed in a fire accidentally started by his dog (the story is probably apocryphal), most of his work was published in 1936, and was later published online.

3. Newton may have been ill all of his life

While some biographers limit his mental illness to the 18 month period during 1692-93, others argue that Isaac Newton suffered from bipolar disorder for most of his life, exhibiting symptoms in early childhood. Newton was a loner as a child, seldom playing with other children his age, instead of engaging in solitary pursuits such as building models of machines and studying their mechanics. His natural father died before he was born, and when his mother remarried he did not get along with his new stepfather. The dislike was returned, and Newton grew to resent his mother for having remarried. He was then sent to live with his maternal grandmother and remained remote from his half-siblings from his mother’s second marriage.

Newton developed a domineering personality, his few friendships throughout his life were with those whom he could overwhelm with his opinions. He also exhibited periods of remorse, during which he wrote out lists of his “sins”, beginning when he was still a child. He was quick to anger, and often violent when angry, lashing out with words and sometimes fists. During his years as a student at Cambridge, Newton wrote in his notes of suicidal thoughts, feelings of isolation, and his readily evident lack of self-esteem. He resented criticism by any other than himself, a feature of his personality which continued through his career when his theories were subject to questioning. The cycle of manic behavior and depression continued throughout his long life.

4. Newton suffered from delusions of grandeur

During his extensive studies of the bible and concurrent with his work in alchemy, which he believed required secrets extracted from the bible in order to succeed, Newton kept notes in which he designated himself to have been selected by God to reveal the secrets of His mysteries to the world. Newton came to believe that the worship of Jesus as divine was heretical, though he did not publish his beliefs during his lifetime. To do so would have placed him a heretic at a time when heretics could be executed under certain circumstances. He considered Jesus to have been a man who, like himself, had been chosen to reveal certain truths, but was subservient to God. Thus Newton rejected the idea of the Trinity.

Newton’s self-appointed status as a messenger chosen to reveal God’s secrets was what drove him to examine the bible, including the geometric dimensions of the Temple, which he found to have been a code for the dimensions of the earth and the heavens. Newton’s personality was such that he avoided even casual conversation with most people other than those who demonstrated marked respect for him, to whom he was often condescending. While a fellow at Trinity College, a position which required ordination as a priest of the Anglican Church, Newton avoided the requirement by arguing that the Mathematics chair should be free from the distractions of church duties in order to concentrate on science, and was granted a dispensation by the King.

5. Newton’s eighteen-month breakdown was recognized by contemporaries

One of the only two close personal relationships developed by Newton during his lifetime was with Nicholas Fatio de Duillier, a protégé with whom he maintained a warm correspondence. The relationship led to speculation among some that since Newton never married he was involved in a homosexual relationship with Fatio. There has never been any evidence of such a relationship revealed in Newton’s voluminous works and correspondence, and there is much evidence that Newton had no interest in either sex, preferring to remain chaste and free from emotional encumbrances. He often wrote complaining of others who attempted to present him to eligible women.

During the period of his breakdown, during which he suffered from tremors, insomnia (in one letter he claimed to have not slept for five days), an inability to eat, delusions and possibly hallucinations, he also sent letters which appeared to his correspondents to be irrational in nature. One of these was to Fatio, and the former regard in which his protégé had held him vanished. Newton claimed in a letter to Samuel Pepys to have lost “my former consistency of mind” and he was struck by apathy and what was referred to by others as melancholia. His evident illness included him being reported to have conversations with persons not present, seemingly responding to voices heard in empty rooms.

6. Newton’s personality led to lengthy disputes with fellow mathematicians

Newton was possessed with a lifelong suspicion that the credit for his work and his discoveries would be stolen by others, both of his contemporaries and those who came later. The obsession led him into a controversy over the development of calculus beginning in 1699, which by 1711 had grown to include claims of plagiarism leveled by Newton toward Gottfried Leibniz. Newton claimed that Leibniz had stolen his work which he began in 1666, but which he did not publish until much later. Leibniz published his work beginning in 1684. Newton’s earlier work did not become published until after his death. The controversy led to Leibniz becoming something of a pariah in the last decade of his life.

Newton created the controversy and used the followers of his version to discredit Leibniz. The controversy was entirely based on Newton’s fear that work similar to his had been arrived at independently and that he was thus not the greatest mathematical mind of his age. The Royal Society established a committee to independently investigate the controversy in 1713, which listened to Newton’s assertions without offering Leibniz an opportunity to present his version, finding in favor of Newton late that year. Newton later claimed that the controversy wasn’t about his fame, which he shunned, but was based instead on his reputation for honesty. In 1716 Leibniz died, and in the twentieth century, most historians agree that the two mathematicians arrived at their discoveries independently.

7. Newton could be vindictive, petty, and vicious

When Gottfried Leibniz died the controversy over the discovery of calculus did not die with him, as Newton continued to use his influence within the Royal Society to enhance his own reputation at the expense of his fellow mathematician, who could no longer offer a defense. Nor was Leibniz the only fellow scientist to feel Newton’s wrath. Robert Hooke developed a theory of gravity controlling the motion of the planets similar to Newton’s, and independently of Newton’s work, which Newton attempted to obscure after Hooke’s death when Sir Isaac assumed Hooke’s former role as head of the Royal Society in London.

Newton and Hooke also clashed over Newton’s work with optics and light, which Hooke offered criticism on, and once Newton was in a position to do so he systematically took steps to move Hooke into obscurity. When Newton took over as the head of the Royal Society Hooke’s papers vanished, including copies of correspondence between Newton and Hooke, between Hooke and architect Christopher Wren, and minutes of the Royal Society, 520 papers in all. They were not rediscovered until the twenty-first century. There was also a story, possibly apocryphal, that when the Royal Society moved to new quarters, Newton removed the only portrait of Hooke done from life, though there is no hard evidence that such a portrait ever existed.

8. Newton prosecuted counterfeiters relentlessly

Newton is remembered primarily as a scientist and mathematician today, with an emerging reputation as a biblical scholar, but for more than half of his adult life he was a government functionary, as first Warden, and later as Master, of the Royal Mint. The positions were obtained for him as sinecures, as a source of income. Newton waited some time for the appointment, at one point claiming that Charles Montagu, responsible for the appointment, bore a grudge against him. When Montagu became Chancellor of the Exchequer he made the appointment, noting that the duties were less than onerous and should not require much of Newton’s time away from his scientific work.

Newton threw himself into the role, investigating counterfeiting and the clipping of coins with enthusiasm, even disguising himself in taverns to uproot counterfeiters, and prosecuting them vigorously. One such counterfeiter was convicted by Newton and after his high-ranking friends succeeded in gaining his release from prison Newton prosecuted him a second time. The evidence which Newton presented and the vigor of his prosecution led to the counterfeiter being convicted and sentenced to death by hanging, after which he was taken down still alive and drawn and quartered. Newton’s zeal led to another 28 convictions and executions for counterfeiting, all of which he pursued with pious glee.

9. The argument that Newton had Asperger’s syndrome

Three of the clinical features of Asperger’s syndrome have been studied as features of Newton’s personality, and other supportive evidence has led some to conclude that Newton suffered from the syndrome. These are social impairment which inhibits developing friendships and which displays a lack of empathy for others; lack of any desire to communicate with others; and complete self-absorption with routine and dominant interests. The observations of others of Newton’s day are often used to support the opinion, including his indifference to his appearance in his days at school, as reported by fellow students at Trinity College.

That the symptoms were present during different times throughout Newton’s career is clear from contemporary writings about him. During his school days at Trinity, the sloppiness of his appearance was noted by several students, as was his all-absorbing focus on his studies and later work. Often he would, by his own admittance, be so absorbed that he would forget to eat. But all three of the symptoms, as well as indifference as to his appearance, are readily explained by other possibilities as well, and diagnosing a condition across three centuries is not an easy exercise. Newton maintained many relationships in writing over his lifetime, and communicated his thoughts with clarity in them, rather than doing so in small talk or lectures.

10. The argument that Newton did not have Asperger’s syndrome

Isaac Newton was small and slightly built as a child, a target for bullying, without the support of parents or siblings. In one of his early notebooks, he wrote of his determination to be the best student in school, the King’s School at Grantham (which remains in operation as of 2018). As with many slight and scholarly boys, he was subject to being ostracized, teased, and bullied, which was the impetus for his being determined to outperform the other boys in schoolwork. No doubt his imperious and dominating nature also contributed to his lack of social acceptance. But there is another possible explanation rather than Aspergers, or some other form of developmental disorder.

Isaac Newton was a stutterer, an affliction with which he struggled for most of his life, which readily explains his lifelong avoidance of social conversation. Even as a Member of Parliament later in life, he avoided public speaking. The affliction could also explain his reluctance to tutor students while holding the Lucasian mathematics chair at Trinity College. His later expressed overreactions to criticism may have been because of an increased embarrassment over his stuttering. Another argument against Asperger’s syndrome was his deft use of his hands; as a student he designed and built working models of windmills and other machinery, demonstrating hand-eye coordination and the proper use of tools, self-taught.

11. He was described as having a difficult personality by his contemporaries

One of the arguments put forth to support the theory that Isaac Newton suffered from what is now known as bipolar disorder is the difficult nature of his personality. Newton’s contemporaries, both friend and foe, described him in less than flattering terms when discussing his social skills. “The most fearful, cautious, and suspicious temper, than I ever knew,” wrote William Whiston, who served as Newton’s deputy in 1701, when Newton held the Lucasian Mathematics chair at Trinity College. Whiston also performed the majority of the duties associated with the position, which Newton turned into a sinecure, not tutoring students or concentrating on the performance of the students in the department. His personality wouldn’t allow him to teach.

When Newton attained his status as a Master of Arts and Major Fellow at Trinity College he began receiving a small stipend from the college, and continued to receive annual support from his mother, which he used beginning in early 1668 to refurbish his rooms. After the college itself took care of the heavy construction Newton had the interior redone to his taste, and went on a spending spree, purchasing carpets, leather chairs, ten additional chairs, several tables and desks, chests, a sofa, glasses, table linens, and a new bed. The spending on his refurbished home has been described by those supporting the theory of bipolar disorder as being symptomatic of a manic phase.

12. Newton’s concentration was such that he often forgot to eat and sleep

Newton demonstrated powers of concentration which served to make him in many ways the prototype of the “absent-minded professor” of later ages. He often breakfasted on the cold dishes which had been set out for him as his supper the night before, having been so deep in thought throughout the night that he forgot to either eat or sleep. Late in life, he told his half-niece that during his days at Cambridge his cat had become fat through eating the meals which sat on his side table as he worked on some problem or another, unnoticed by him. On being reminded of his meal sitting unattended, he would often take one or two bites of the repast while standing, before being drawn away again by whatever was occupying his attention, according to his secretary at Cambridge.

John Locke, who like Newton was a Fellow of the Royal Society, once wrote that though he considered Newton a friend, he was concerned that he was difficult at times to deal with, “and a little too apt to raise in himself suspicions where there is no ground”. This and similar observations by contemporaries and later biographers led to Newton being described as withdrawn and forgetful due to a disturbed mind, afraid to engage in social activity because of a suspicious and paranoid personality. His fears of criticism led to his delays in publishing much of his work until they were overridden by the fear that another would receive the credit for his discoveries. At his death, much of his work remained unpublished.

13. Newton answered criticism with acrimony as much as he did with reason

When Newton’s thoughts and discoveries on the nature of light were published he received criticism on both his theories and his lack of acknowledging the contributions of others on which he had relied to form his conclusions. The failure to acknowledge contributions from others was a frequent accusation directed at Newton throughout his career. When John Flamsteed, an English astronomer whose work had been used by Newton while forming his postulations on gravity, complained that Newton had failed to properly cite his contributions it started a long quarrel between the two scientists. Flamsteed complained in writing to another member of the Royal Society.

Flamsteed’s complaint was that Newton, in arriving at his conclusions over gravity, had “used the ore he had dug”. Newton responded with a comment along the lines of if Flamsteed had dug the ore it was he (Newton) who had formed the useless rock into a gold ring. Still, the comments must have stung Newton, for he began to exhibit an aversion to publishing his work, despite his promises to support the Royal Society by diligently doing so as regularly as possible. Newton once wrote to Leibniz of his hesitation to publish (before their quarrel), “…I conceive myself to have discovered the surest of explanations, but I refrain from publishing books for fear that disputes and controversies may be raised against me by ignoramuses.” Newton was referring to his discoveries of the properties of light.

14. Newton was undistracted by the arts

Isaac Newton acquired a library of 1,896 books by the time of his death, none of which were the works of Geoffrey Chaucer, Edmund Spenser, or William Shakespeare, though copies of two of the latter’s works, Hamlet and The Tempest, were in his collection. He did own copies of epic poems by John Milton, but referred to poetry itself as “ingenious nonsense”. According to William Stukeley, Newton once admitted to attending an opera, and said of it, “The first act I heard with pleasure, the second stretched my patience, at the third I ran away”. Once when listening to a harpsichord being played by Handel, Newton had no comment about the music. Instead, he observed the mechanics of the musician’s hands as he played.

Perhaps because of his avoidance of the arts Newton’s interactions with peers were curtailed. He was unable to join in the discussions in drawing rooms and parlors of the latest book, the latest play, the latest composition because he had not read, seen, or heard them. Already inexperienced in the social grace of conversation, his lack of knowledge would have made him appear uninformed and possibly even ill-bred in that time of class distinctions. In his publications, and even in his private letters Newton’s writing was spare in its use of adjectives and other tools of the writer. Newton’s indifference to the arts did not extend to landscaped gardens, one of which he meticulously kept while at Cambridge.

15. Newton has been described as being a hypochondriac

Isaac Newton, other than the period in which he suffered a breakdown during his alchemy experiments, lived a long and relatively healthy life, with few periods of sickness noted in his letters and those of his contemporaries. Yet he was described by many supporting the idea of mental health issues affecting him as suffering from hypochondria. The accusations are based on Newton’s alchemy experiments, in which he also mixed various medicinal potions along with his search for the elixir of life, and his reliance on a balm of the day known as Lucatello’s Balsome, which promised relief for many ailments, including measles, dog bite, and the illness for which Newton allegedly took it, consumption.

Newton did write of being confined to his, “Chamber by a cold” at one juncture, though he was about his business again within a week and it would be improbable that during such a long life he would not have suffered many colds, especially given the knowledge of medicine and contagion at the time. The use of such balms and nostrums was commonplace during Newton’s lifetime. If Newton did believe that he had consumption there are no records of his consulting a physician for relief, nor of him participating in the taking of healthful waters then believed to relieve the condition.

16. He was a solitary and reclusive, preferring his own company to that of others

Over time, Isaac Newton developed the personality which led him to prefer to be alone, avoiding social contacts except when necessary for the advancement of his work. In his writings and those of his contemporaries, he exhibited little in the way of a sense of humor, and he did not easily share his achievements with others by making note of their contributions. He did not express his emotions other than in bursts of anger; other feelings remained under strict self-control. He did not speak or write of his own desires, and the only indications of his possessing a sense of remorse were in the lists of “sins” he prepared for himself while in his youth.

He was not free from a sense of sexual desire, since he wrote of the means to control it, and thus remain chaste, a condition in which he apparently remained throughout his life. “The way to chastity is not to struggle with incontinent thoughts but to avert the thoughts by some imployment (sic), or by reading, or by meditating on other things, or by convers”, Newton told a relative late in his lifetime. The only record of any potential romantic involvement was an adolescent one, before he began his academic career. Probably the best description of Newton’s personality comes from Humphrey Newton, who served as his secretary for a time at Trinity College. “His behavior was mild and meek, without anger, peevishness, or passion, so free from that, that you might take him for a stoic.” But clearly, he was not without his demons, as human as are all.

Where do we find this stuff? Here are our sources:

“Mercury Poisoning: A probable cause of Isaac Newton’s physical and mental ills”. L. W. Johnson, M. L. Wobarsht, Notes and Records, The Royal Society Journal of the History of Science. July 1, 1979

“Isaac Newton: The Last Sorcerer”. Michael White. 1997

“Isaac Newton’s Personal Life”. The Newton Project, Oxford University. 2018. Online

“Priest of Nature: The Religious Worlds of Isaac Newton”. Rob Iliffe. 2017

“Balancing Newton’s Mind: his singular behavior and his madness of 1692-93”. Milo Keynes, Notes and Records, The Royal Society Journal of the History of Science. September 20, 2008

“The Newton-Leibniz Controversy”. Gerald L. Alexanderson, Leonard F. Klosinski, Bulletin of the American Mathematics Society. February 1, 2016

“Robert Hooke, Britain’s Leonardo, papers go online”. Roger Highfield, The Telegraph. October 8, 2007

“Newton and the Counterfeiter: The Unknown Detective Career of the World’s Greatest Scientist”. Thomas Levenson. 2009

“Isaac Newton Used This Recipe in His Hunt to Make a Philosopher’s Stone”. Danny Lewis, Smithsonian Magazine, April 11, 2016

“Notes In Which Isaac Newton Sought to Unlock Secrets Of Bible Sold At Auction”. TOI STAFF, Times Of Israel, 13 December 2020

“Isaac Newton: Was He a Jerk Due to Asperger’s?”. Ross Pomeroy, Real Clear Science, October 31, 2013

“Einstein and Newton showed signs of Autism”. Hazel Muir, New Scientist. April 30, 2003

“The Personality of Isaac Newton”. Milo Keynes, The Royal Society. 1995

“Why Was Isaac Newton Such a Jerk?” Stephen Ross Pomeroy, Forbes Online. November 4, 2013

“Celebrity Meltdown: Isaac Newton (1642-1727)”. Staff of Psychology Today. November 1999

“Flaws of Gravity”. Christopher Hitchens, Vanity Fair. April 2008

“In the Presence of the Creator: Isaac Newton and his Times”. Gale Christianson. 1984

“How Isaac Newton Lost His Marbles and more medical mysteries, marvels, and mayhem”. Dr. Jim Leavesley and George Biro. 2010

“The Cambridge Companion to Newton”. Bernard I. Cohen, George E. Smith, editors. 2002