 |
| Isaac Newton |
Born on January 4, 1643, in
Woolsthorpe, England, Isaac Newton
was an established physicist and mathematician, and is credited as one of the
great minds of the 17th century Scientific Revolution. With discoveries in
optics, motion and mathematics, Newton developed the principles of modern
physics. In 1687, he published his most acclaimed work, Philosophiae,
Natrualis, Principia Mathematica (Mathematical Principles of Natural
Philosophy), which has been called the single-most influential book on
physics. Newton died in London on March 31, 1727.
On January 4, 1643, Isaac Newton was
born in the hamlet of Woolsthorpe, Lincolnshire, England. He was the only son
of a prosperous local farmer, also named Isaac Newton, who died three months
before he was born. A premature baby born tiny and weak, Newton was not
expected to survive. When he was 3 years old, his mother, Hannah Ayscough
Newton, remarried a well-to-do minister, Barnabas Smith, and went to live with
him, leaving young Newton with his maternal grandmother. The experience left an
indelible imprint on Newton, later manifesting itself as an acute sense of
insecurity. He anxiously obsessed over his published work, defending its merits
with irrational behavior.
At age 12, Newton was reunited with
his mother after her second husband died. She brought along her three small
children from her second marriage. Newton had been enrolled at the King's
School in Grantham, a town in Lincolnshire, where he lodged with a local
apothecary and was introduced to the fascinating world of chemistry. His mother
pulled him out of school, for her plan was to make him a farmer and have him
tend the farm. Newton failed miserably for he found farming monotonous.
He soon was returned to King's School
to finish his basic education. Perhaps sensing his innate intellectual
abilities, his uncle, a graduate of the University of Cambridge's Trinity
College, persuaded Newton's mother to have him enter the university. Newton
enrolled in a program similar to a work study in 1661, and subsequently waited
on tables and took care of wealthier students' rooms.
When Newton arrived at Cambridge, the
Scientific Revolution of the 17th century was already in full force. The
heliocentric view of the universe—theorized by astronomers Nicolaus
Copernicus and Johannes Kepler, and later refined by Galileo—was well
known in most European academic circles. Philosopher René Descartes
had begun to formulate a new conception of nature as an intricate, impersonal,
and inert machine. Yet, as with most universities in Europe, Cambridge was
steeped in Aristotelian philosophy and view of nature resting on a geocentric
view of the universe and dealing with nature in qualitative rather than
quantitative terms.
During his first three years at
Cambridge, Newton was taught the standard curriculum, but was fascinated with
the more advanced science. All his spare time was spent reading from the modern
philosophers. The result was a less-than-stellar performance, but one that is
understandable given his dual course of study.
It was during this time that Newton
kept a second set of notes, entitled "Quaestiones Quaedam
Philosophicae" ("Certain Philosophical Questions"). The
"Quaestiones" reveal that Newton had discovered the new conception of
nature that provided the framework for the Scientific Revolution.
Though Newton graduated with no honors
or distinctions, his efforts won him the title of scholar and four years of
financial support for future education. Unfortunately, in 1665, the Great
Plague that was ravaging Europe had come to Cambridge, forcing the university to
close. Newton returned home to pursue his private study. It was during this
18-month hiatus that he conceived the method of infinitesimal calculus, set
foundations for his theory of light and color, and gained significant insight
into the laws of planetary motion—insights that eventually led to the
publication of his Principia in 1687. Legend has it that, at this time,
Newton experienced his famous inspiration of gravity with the falling apple.
With the threat of plague subsided in
1667, Newton returned to Cambridge and was elected a minor fellow at Trinity
College, still not considered a standout scholar. However, in the ensuing
years, his fortune improved. Newton received his Master of Arts degree in 1669,
before he was 27. During this time, he came across Nicholas Mercator's
published book on methods for dealing with infinite series. Newton quickly
wrote a treatise, De Analysi, expounding his own wider ranging results. He
shared this with friend and mentor Isaac Barrow, but didn't include his name as
author.
In June 1669, Barrow shared the
unaccredited manuscript with British mathematician John Collins. In August
1669, Barrow indentified its author to Collins as "Mr. Newton ... a very
young ... but of an extraordinary genius and proficiency in these things."
Newton's work was brought to the attention of the mathematics community for the
first time. Shortly afterward, Barrow resigned his Lucasian Professorship at
Cambridge, and Newton assumed the chair.
As professor, Newton was exempted from
tutoring but required to deliver an annual course of lectures. He chose to
deliver his work on optics as his initial topic. Part of Newton's study of
optics was aided with the use of a reflecting telescope that he designed and
constructed in 1668—his first major public scientific achievement. This
invention helped prove his theory of light and color. The Royal Society asked
for a demonstration of his reflecting telescope in 1671, and the organization's
interest encouraged Newton to publish his notes on light, optics and color in
1672; these notes were later published as part of Newton's Opticks: Or, A
treatise of the Reflections, Refractions, Inflexions and Colours of Light.
However, not everyone at the Royal
Academy was enthusiastic about Newton's discoveries in optics. Among some of
the dissenters was Robert Hooke,
one of the original members of the Royal Academy and a scientist who was
accomplished in a number of areas, including mechanics and optics.
In his paper, Newton theorized that
white light was a composite of all colors of the spectrum, and that light was
composed of particles. Hooke believed that light was composed of waves. Hooke
quickly condemned Newton's paper in condescending terms, and attacked Newton's
methodology and conclusions.
Hooke was not the only one to question
Newton's work in optics. Renowned Danish scientist Christiaan Huygens and a
number of French Jesuits also raised objections. But because of Hooke's
association with the Royal Society and his own work in optics, his criticism
stung Newton the worst. Unable to handle the critique, he went into a rage—a
reaction to criticism that was to continue throughout his life.
Newton denied Hooke's charge that his
theories had any shortcomings, and argued the importance of his discoveries to
all of science. In the ensuing months, exchange between the two men grew more
acrimonious and soon Newton threatened to quit the Society altogether. He
remained only when several other members assured him that the Fellows held him
in high esteem.
However, the rivalry between Newton
and Hooke would continue for several years thereafter. Then, in 1678, Newton
suffered a complete nervous breakdown and the correspondence abruptly ended.
The death of his mother the following year caused him to become even more
isolated, and for six years he withdrew from intellectual exchange except when
others initiated correspondence, which he always kept short.
During his hiatus from public life,
Newton returned to his study of gravitation and its effects on the orbits of
planets. Ironically, the impetus that put Newton on the right direction in this
study came from Robert
Hooke. In a 1679 letter of general correspondence to Royal Society members
for contributions, Hooke wrote to Newton and brought up the question of
planetary motion suggesting that a formula involving the inverse squares might
explain the attraction between planets and the shape of their orbits.
Subsequent exchanges transpired before
Newton quickly broke off the correspondence once again. But Hooke's idea was
soon incorporated into Newton's work on planetary motion and from his notes it
appears he had quickly drawn his own conclusions by 1680, though he kept his
discoveries to himself.
In early 1684, in a conversation with
fellow Royal Society members Christopher Wren and Edmond Halley, Hooke made is
case on the proof for planetary motion. Both Wren and Halley thought he was on
to something, but pointed out that a mathematical demonstration was needed. In
August 1684, Halley traveled to Cambridge to visit with Newton, who was coming
out of his seclusion. Halley idly asked him what shape the orbit of a planet
would take if its attraction to the sun followed the inverse square of the
distance between them (Hooke's theory).
Newton knew the answer due to his
concentrated work for the past six years and replied "an ellipse."
Newton claimed to have solved the problem some eighteen years ago during his
hiatus from Cambridge and the plague, but he was unable to find his notes. Halley
persuaded him to work out the problem mathematically and offered to pay all
costs so that the ideas might be published.
Publishing 'Principia'
In 1687, after 18 months of intense
and effectively non-stop work, Newton published Philosophiae, Natrualis,
Principia Mathematica (Mathematical Principles of Natural Philosophy).
Said to be the single-most influential book on physics and possibly all of
science, it is most often known as Principia and contains information on
nearly all of the essential concepts of physics, except energy.
The work offers an exact quantitative
description of bodies in motion in three basic laws: 1) A stationary body will
stay stationary unless an external force is applied to it; 2) Force is equal to
mass times acceleration, and a change in motion is proportional to the force
applied; and 3) For every action, there is an equal and opposite reaction.
These three laws not only helped explain elliptical planetary orbits but nearly
every other motion in the universe: how the planets are kept in orbit by the
pull of the sun’s gravity; how the moon revolves around earth and the moons of
Jupiter revolve around it; how comets revolve in elliptical orbits around the
sun.
The laws also allowed Newton to
calculate the mass of each planet, calculate the flattening of the Earth at the
polls and the bulge at the equator, and how gravitational pull of the sun and
moon create the Earth’s tides. In Newton's account, gravity kept the universe
balanced, made it work, and brought heaven and earth together in one great
equation.
Upon the publication of the first
edition of Principia, Robert Hooke
immediately accused Newton of plagiarism, claiming that he had discovered the
theory of inverse squares and that Newton had stolen his work. The charge was
unfounded, as most scientists knew, for Hooke had only theorized on the idea
and had never brought it to any level of proof. However, Newton was furious and
strongly defended his discoveries.
He withdrew all references to Hooke in
his notes and threatened to withdraw from publishing the subsequent edition of Principia
altogether. Halley, who had invested much of himself in Newton's work, tried to
make peace between the two men. While Newton begrudgingly agreed to insert a
joint acknowledgement of Hooke's work (shared with Wren and Halley) in his
discussion of the law of inverse squares, it did nothing to placate Hooke.
As the years went on, Hooke's life
began to unravel. His beloved niece and companion died the same year that Principia
was published, in 1687. As Newton's reputation and fame grew, Hooke's declined,
causing him to become even more bitter and loathsome toward his rival. To the
bitter end, Hooke took every opportunity he could to offend Newton. Knowing
that is rival would soon be elected president of the society, Hooke refused to
retire until the year of his death, in 1703.
International Prominence
Principia immediately raised Newton to
international prominence, and he thereafter became more involved in public
affairs.
Consciously or unconsciously, he was
ready for a new direction in life. He no longer found contentment in his
position at Cambridge and he was becoming more involved in other issues. He
helped lead the resistance to King James II's attempts to reinstitute Catholic
teaching at Cambridge and in 1689, he was elected to represent Cambridge in
Parliament.
While in London, Newton acquainted
himself with a broader group of intellectuals and became acquainted with
political philosopher John Locke.
Though many of the scientists on the continent continued to teach the
mechanical world according to Aristotle, a young
generation of British scientists became captivated with Newton's new view of
the physical world and recognized him as their leader. One of these admirers
was Nicolas Fatio de Duillier, a Swiss mathematician who Newton befriended
while in London.
However, within a few years, Newton
fell into another nervous breakdown in 1693. The cause is open to speculation:
his disappointment over not being appointed to a higher position by England's
new monarchs, William III and Mary II, or the
subsequent loss of his friendship with Duillier; exhaustion from being
overworked; or perhaps chronic mercury poisoning after decades of alchemical
research. It's difficult to know the exact cause, but evidence suggests that
letters written by Newton to several of his London acquaintances and friends,
including Duillier, seemed deranged and paranoiac, and accused them of betrayal
and conspiracy.
Oddly enough, Newton recovered
quickly, wrote letters of apology to friends, and was back to work within a few
months. He emerged with all his intellectual facilities intact, but seemed to
have lost interest in scientific problems and now favored pursuing prophecy and
scripture and the study of alchemy. While some might see this as work beneath
the man who had revolutionized science, it might be more attributed to Newton
responding to the issues of the time in turbulent 17th century Britain. Many
intellectuals were grappling with the meaning of many different subjects, not
least of which were religion, politics and the very purpose of life. Modern
science was still so new, no one knew for sure how it measured up against older
philosophies.
In 1696, Newton was able to attain the
governmental position he had long sought: warden of the Mint; after acquiring
this new title, he permanently moved to London and lived with his niece,
Catherine Barton. She was the mistress of Lord Halifax, a high-ranking
government official who was instrumental in having Newton promoted, in 1699, to
master of the Mint—a position that he would hold until his death. Not to be
considered a mere honorary position, Newton approached the job with earnest,
reforming the currency and severely punishing counterfeiters. As Master of the
Mint, Newton moved the British currency, the Pound Sterling, from the silver to
the gold standard.In 1703, Newton was elected president of the Royal Society
upon Robert
Hooke's death.
In 1705, he was knighted by Queen Anne
of England. At this point in his life, Newton's career in science and discovery
had given way to a career of political power and influence.
Newton never seemed to understand the
notion of science as a cooperative venture, and his ambition and fierce defense
of his own discoveries continued to lead him from one conflict to another with
other scientists. By most accounts, Newton's tenure at the society was
tyrannical and autocratic; he was able to control the lives and careers of
younger scientists with absolute power.
In 1705, in a controversy that had
been brewing for several years, German mathematician Gottfried Liebniz
publically accused Newton of plagiarizing his research, claiming he had
discovered infinitesimal calculus several years before the publication of Principia.
In 1712, the Royal Society appointed a committee to investigate the matter. Of
course, with Newton as president, he was able to appoint the committee members
and oversee its investigation. Not surprisingly, the committee concluded
Newton's priority over the discovery.
That same year, in another of Newton's
more flagrant episodes of tyranny, he published without permission the notes of
astronomer John Flamsteed. It seems the astronomer had collected a massive body
of data from his years at the Royal Observatory at Greenwich, England. Newton
had requested a large volume of Flamsteed's notes for his revisions to
Principia. Annoyed when Flamsteed wouldn't provide him more information as
quickly as he wanted it, Newton used his influence as president of the Royal
Society to be named the chairman of the body of "visitors"
responsible for the Royal Observatory.
He then tried to force the immediate
publication of Flamsteed's catalogue of the stars, as well as all of
Flamsteed's notes, edited and unedited. To add insult to injury, Newton
arranged for Flamsteed's mortal enemy, Edmund Halley, to prepare the notes for
press. Flamsteed was finally able to get a court order forcing Newton to cease
his plans for publication and return the notes—one of the few times that Newton
was bested by one of his rivals.
Toward the end of this life, Newton
lived at Cranbury Park, near Winchester, England, with his niece, Catherine
(Bancroft) Conduitt, and her husband, John Conduitt. By this time, Newton had
become one of the most famous men in Europe. His scientific discoveries were
uchallenged. He also had become wealthy, investing his sizeable income wisely
and bestowing sizeable gifts to charity. Despite his fame, Newton's life was
far from perfect: He never married or made many friends, and in his later
years, a combination of pride, insecurity and side-trips on peculiar scientific
inquiries led even some of his few friends to worry about his mental stability.
By the time he reached 80 years of
age, Newton was experiencing digestion problems, and had to drastically change
his diet and mobility. Then, in March 1727, Newton experienced severe pain in
his abdomen and blacked out, never to regain consciousness.
He died the next day, on March 31,
1727, at the age of 85.
Isaac Newton's fame grew even more
after his death, as many of his contemporaries proclaimed him the greatest
genius that ever lived. Maybe a slight exaggeration, but his discoveries had a
large impact on Western thought, leading to comparisons to the likes of Plato, Aristotle and Galileo.
Although his discoveries were among
many made during the Scientific Revolution, Isaac Newton's universal principles
of gravity found no parallels in science at the time. Of course, Newton was
proven wrong on some of his key assumptions. In the 20th century, Albert Einstein
would overturn Newton's concept of the universe, stating that space, distance
and motion were not absolute but relative, and that the universe was more
fantastic than Newton had ever conceived.
Newton may not have been surprised: In
his later life, when asked for an assessment of his achievements, he replied,
"I do not know what I may appear to the world; but to myself I seem to
have been only like a boy playing on the seashore, and diverting myself now and
then in finding a smoother pebble or prettier shell than ordinary, while the
great ocean of truth lay all undiscovered before me."
Tiada ulasan:
Catat Ulasan