Monday July 5, 2021’s Smile of the Day: The Principia

On this Day:

In 1687, Isaac Newton’s great work, Principia, was published by the Royal Society in England, outlining his laws of motion and universal gravitation.

Philosophiæ Naturalis Principia Mathematica (Mathematical Principles of Natural Philosophy) by Isaac Newton, often referred to as simply the Principia, is a work in three books written in Latin, first published 5 July 1687. After annotating and correcting his personal copy of the first edition, Newton published two further editions, during 1713 with errors of the 1687 corrected, and an improved version of 1726.

The Principia states Newton’s laws of motion, forming the foundation of classical mechanics; Newton’s law of universal gravitation; and a derivation of Johannes Kepler’s laws of planetary motion (which Kepler had first obtained empirically).

The Principia is considered one of the most important works in the history of science. The French mathematical physicist Alexis Clairaut assessed it in 1747: “The famous book of Mathematical Principles of Natural Philosophy marked the epoch of a great revolution in physics. The method followed by its illustrious author Sir Newton … spread the light of mathematics on a science which up to then had remained in the darkness of conjectures and hypotheses.” (per Wikipedia).

Isaac Newton’s (1642-1725) most influential writing was his Philosophiae Naturalis Principia Mathematica (The Mathematical Principles of Natural Philosophy), published in sections between the years 1667-86. It united two competing strands of natural philosophy—experimental induction and mathematical deduction—into the scientific method of the modern era. His emphasis on experimental observation and mathematical analysis changed the scope and possibilities of science.

Throughout the medieval period European scholars had relied heavily on the teachings of Aristotle (384-322 b.c.) and the works of a few Christian philosophers. Then, in the late fifteenth century, there was a rediscovery and popularization of other ancient writers, such as Plato (427-347 b.c.), who opposed many of Aristotle’s ideas. The intellectual community began to debate the works of these and other ancient writers, often challenging firmly held academic and religious beliefs. However, these debates were framed by the question of which of the ancient writers was correct. Some thinkers began to question the basis of such debate, arguing that new forms of thinking could go beyond the works of the ancients.

René Descartes (1596-1650) found the Aristotelian methods he was taught to be entirely unsatisfactory. He considered them to be based on false assumptions. The only knowledge he found certain was mathematics, and so he used mathematical deduction as the basis of his entire scientific method and philosophy. Descartes’ most comprehensive work was his Principia Philosophiae (1644), which attempted to put the whole universe on a mathematical foundation, reducing the study of everything to that of mechanics. For Descartes, knowledge could only be gained from deduction from fundamental principles.

Deduction is the method by which consequences are derived from established premises. From the observed or established facts predictions of future events or possible consequences can be deduced. In a sense it is an educated guess. For example, from the premise that all swans are white, if the bird you observe is a swan, then deductively the bird must also be white. As long as the premise and observation are correct then the conclusion must be true. However, deduction can never prove the premise, no matter how much supporting evidence is gathered, as a single contradictory result will overturn the rule. Black swans were discovered in Australia, and so the deduction was incorrect.

Galileo Galilei (1564-1642) also championed the notion of deduction, although in his case from experimental observations. He found the academic focus on ancient knowledge to be suffocating and limiting. He used experimental deduction to show that the universe was not as he had been taught. He observed the mountains and craters of the Moon, which tradition held was a perfect sphere. He saw moons orbiting Jupiter, and observed that the Milky Way was made up of tiny stars. From these observations he deduced that Earth was not the center of the universe, that the planets were not perfect and unchanging, and that the Copernican theory (that Earth revolved around the Sun, not vice versa) was correct.

An alternative to both the reliance on ancient writings and the deductive method was proposed by Francis Bacon (1561-1626). Bacon dismissed deduction as merely the logic of argumentation. He preferred induction, which is the process of reasoning from particular events to general rules. For example, when numerous observations of swans also gave the result that all observed swans are white, then it was induced that all swans were white. As we have seen, this is not correct.

Bacon did not think that scientists should seek to prove particular theories as Galileo had done. He proposed that scientists should unselectively and objectively collect facts from experiment and observation and then organize and classify them. When enough facts had been collected, then they would be generalized to create a universal theory.

Another inductive thinker was Robert Boyle (1627-1691). His 1661 work The Sceptical Chemist argued against Aristotle’s views on the composition of matter. His experimental work was wide and varied, and only when he had performed numerous variations of an experiment would he then induce general rules to explain the results.

Like these other scientists, Newton also found the stale debates over ancient writings to be frustrating. Initially he turned to the mathematical deduction of Descartes as an escape from Aristotle. However, the more he considered Descartes’s ideas the more he disagreed. He was also influenced by the works of Nicolaus Copernicus (1473-1543), Johannes Kepler (1571-1630), and Galileo, and began to combine them all together. The work that resulted was his Principia Mathematica.

Newton’s Principia was mainly a description of the laws of planetary motion. However, it also contained more universal material that was to influence the way all science developed. In effect it combined the methods of induction and deduction. Newton agreed with the inductionists that first a scientist should establish the facts by careful observation and experiment. However, he then proposed using deduction from already known principles to formulate new hypothetical principles. Then laws of nature could then be induced. These new laws could be tested by further experiment and observation, and so on.

The Principia received good reviews, perhaps because some were written by close friends of Newton. The book was an all-encompassing explanation of physics, starting with definitions of mass, force, and motion, providing mathematical explanations of these principles, and going on to explain planetary motion, lunar motion, the ocean tides, and many other things besides.

Descartes had stressed the importance of mathematics, and on this point Newton agreed. The Principia established mathematics as the language of science. Mathematics became a means of knowing about the universe. However, the Principia was directly, and deliberately, opposed to Descartes’ philosophy. Newton fundamentally disagreed with the separation of spirit from matter that existed in Descartes’ mechanical view of the world. In part Newton’s work was an attempt to restore the place of God in science. Newton used his mathematical method to show that Descartes’ system of mechanics was impossible.

However, despite the problems with Descartes’ theories they remained popular on the European continent, particularly in France, for nearly one hundred years. There were, however, a number of non-British scientists who followed Newton’s ideas. The prominent French intellectual Voltaire (1694-1778) was in England at the time of Newton’s funeral, and was impressed with the scientific culture he found there. He wrote a glowing description of the British intellectual climate, but these writings were immediately banned in France.

The Principia provided a standard for doing scientific investigations, and with his other published works, such as Opticks (1704), formed the cornerstone for the modern scientific method. It offered a coherent method that seemed free of the occult and reliance on the ancients. However, Newton’s influences included alchemy, unorthodox religious ideas, and a belief that God had given the ancients the true secrets of science and religion.

The Principia’s focus on experiment and observation seems to owe much to the ideas of Bacon. Yet Newton had been more strongly affected by alchemical philosophy, partly because of its mystical and religious elements. He found alchemy’s reliance on experiment to be more solid than many other forms of study. He also preferred its description of the universe as a living force over the mechanical philosophy of Descartes. Newton wrote over a million words on his alchemical studies, but published nothing.

Newton had been careful to include God in his overall plan of the universe. Against Newton’s wishes later followers of his ideas tended to reduce, or eliminate completely, the religious aspect of his theories. Later editions of the Principia often edited out the philosophical sections, and emphasized Newton’s mechanics. In a sense the mechanical views of Descartes were eventually triumphant, but only within the setting of Newton’s theories.

Newton’s success enabled him to wield great influence in British scientific affairs. He was careful to promote the careers of those who supported his ideas, and obstruct those who opposed him. A culture of Newtonianism grew, helping to spread the ideas and changing the way science was performed. Britain developed a more practical and hands-on scientific approach than the rest of Europe. The emphasis on experiments was different from the contemplative, hands-off philosophy that remained popular elsewhere.

Newton’s methods lent themselves easily to everyday applications in mining, agriculture, and industry. Newtonian mechanics could be applied to drain swamps, construct bridges, and pump air into deep mines. Newton’s writings helped change the perspective of his followers, and they saw the world with practical, and mechanical, eyes.

The ideas of the Principia were used outside of science as well. Indeed, Newtonian mechanics was applied to almost anything, including society itself. John Locke’s (1632-1704) democratic philosophy, one of the sparks of the revolutionary period, used Newtonian concepts. Newton even revolutionized the Freemasons (a fraternal order who adopted the rites of ancient religious orders), who introduced new rituals modeled on his philosophy.

Newton’s writings took on the form of doctrine to many later scientists, particularly in England. His findings were often held to be unshakable, even when experiments and analysis using his own method showed them to be wrong. In the eighteenth century many physicists insisted that there were only seven colors, the ones Newton had shown with his prisms. Work that contradicted the old master was discouraged or denied. In nineteenth-century England there was fierce resistance to the wave-theory of light, as it opposed Newton’s corpuscular model. While the culture of Newtonianism helped spark the Industrial Revolution, it later held back research into new areas.

Newton’s ideas were practical, and his method allowed predictions and discoveries to be made. Perhaps the most spectacular use of Newton’s laws of planetary motion were the calculations made by U. J. J. Le Verrier (1811-1877). On the basis of slight variations from Newtonian calculations of the orbit of Uranus he predicted the existence of a new planet, Neptune. However, a similar wobble in the orbit of Mercury was shown by Albert Einstein (1879-1955) not to be caused by another planet, but rather due to effects of relativity, which was to supersede Newtonian mechanics in the twentieth century (per David Tulloch –

First, a Story:

Isaac Newton was an amazing guy, with his discovery of the laws of gravity and such…

But his brother Fig was a bit fruity…

Second, a Song:

Neil deGrasse Tyson (born October 5, 1958) is an American astrophysicist, planetary scientist, author, and science communicator. Tyson studied at Harvard University, the University of Texas at Austin, and Columbia University. From 1991 to 1994, he was a postdoctoral research associate at Princeton University. In 1994, he joined the Hayden Planetarium as a staff scientist and the Princeton faculty as a visiting research scientist and lecturer. In 1996, he became director of the planetarium and oversaw its $210 million reconstruction project, which was completed in 2000. Since 1996, he has been the director of the Hayden Planetarium at the Rose Center for Earth and Space in New York City. The center is part of the American Museum of Natural History, where Tyson founded the Department of Astrophysics in 1997 and has been a research associate in the department since 2003.

From 1995 to 2005, Tyson wrote monthly essays in the “Universe” column for Natural History magazine, some of which were later published in his books Death by Black Hole (2007) and Astrophysics for People in a Hurry (2017). During the same period, he wrote a monthly column in StarDate magazine, answering questions about the universe under the pen name “Merlin”. Material from the column appeared in his books Merlin’s Tour of the Universe (1998) and Just Visiting This Planet (1998). Tyson served on a 2001 government commission on the future of the U.S. aerospace industry and on the 2004 Moon, Mars and Beyond commission. He was awarded the NASA Distinguished Public Service Medal in the same year. From 2006 to 2011, he hosted the television show NOVA ScienceNow on PBS. Since 2009, Tyson has hosted the weekly podcast StarTalk. A spin-off, also called StarTalk, began airing on National Geographic in 2015. In 2014, he hosted the television series Cosmos: A Spacetime Odyssey, a successor to Carl Sagan’s 1980 series Cosmos: A Personal Voyage. The U.S. National Academy of Sciences awarded Tyson the Public Welfare Medal in 2015 for his “extraordinary role in exciting the public about the wonders of science” (per Wikipedia).

Big Think is a multimedium web portal founded in 2007 by Victoria Brown and Peter Hopkins. The website is a collection of interviews, presentations, and roundtable discussions with experts from a wide range of fields. Victoria Brown is the acting CEO. Peter Hopkins is the acting president of the company.

The company began when the pair met while working with Google Video to digitize the VHS archives of the Charlie Rose show in 2006. Brown and Hopkins began contemplating how to organize information into “short-form intellectual videos targeting online audiences”. They envisioned “an online platform where the world’s leading experts could weigh in on current issues”. Hopkins envisioned the platform as being a YouTube for intellectuals.

In 2008 they launched with only video content. The materials involve short clips but with enough content so that they foster thinking, learning, and debate.

In 2009, they branched into blogs and written content. Their first notable blogger was Dr. Michio Kaku. Other personalities include Angelina Jolie, who joined a panel of experts in a discourse over displaced children in Iraq, and Esther Dyson who talked about the opportunities from space exploration.

In 2012, Big Think started live-streaming and providing individuals and companies with “real-time interaction with notable guests”. The platform also serves as a resource for educators and researchers, facilitating online learning. As of March 2012, the Big Think YouTube channel passed 20 million views, and the video archive of the website included more than 12,000 clips from 2000+ experts.

Big Think has created video series on ‘Courageous Collaborations’, ‘Academic Freedom’ and ‘Education Innovation’ sponsored by The Charles Koch Foundation. (per Wikipedia).

Here is Neil deGrasse Tyson in his Big Think video on Sir Isaac Newton.  I hope you enjoy this!


Thought for the Day:

“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 in now and then finding a smoother pebble or a prettier shell than ordinary, whilst the great ocean of truth lay all undiscovered before me.” – Isaac Newton

Have a great day!

Dave & Colleen

© 2021 David J. Bilinsky and Colleen E. Bilinsky

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