Posts Tagged ‘Isaac Newton’
“If you would be a real seeker after truth, it is necessary that at least once in your life you doubt, as far as possible, all things.”*…
René Descartes, the founder of modern philosophy, was furiously condemned by his contemporaries. Why did they fear him? Sandrine Parageau explains…
The French philosopher René Descartes (1596-1650) is generally presented as one of the founders of modern Western philosophy and science, the man who made reason the principle of the search for truth, and who formulated the cogito, ‘I think, therefore I am.’ His assertion of mind-body dualism has given rise to a great number of objections over time, from those of 17th-century theologians to those of 20th-century feminists. In France, even though the decision of the 1792-95 National Convention to transfer Descartes’s remains to the Pantheon in Paris was not followed through, the philosopher is nonetheless regarded as ‘un grand homme’, a national hero, and being labelled ‘Cartesian’ is still today a compliment that emphasises one’s common sense, good judgment and methodical use of reason.
Yet Descartes was not always the undisputed champion of reason that he is today. In 17th-century England and the Netherlands, he was publicly and repeatedly accused of being a fraud and of lying to his readers so as to manipulate them into becoming his disciples. Of course, as one would expect, many intellectual and scientific objections were raised by his contemporaries against Descartes’s philosophy. But those ad hominem allegations were of a different nature altogether: they implied that the French philosopher resorted to well-crafted and dishonest strategies to make his readers ignorant, and therefore gullible, with the aim of making them submit to his control. Thus, according to those critics, the founder of modern science was, in truth, a purveyor of ignorance.
Such an accusation was made for example by the Protestant scholar and theologian Meric Casaubon (1599-1671 [a classicist and the first translators of the Meditations of Marcus Aurelius into English]), a Geneva-born clergyman of the Church of England, in a long manuscript letter on ‘general learning’ written in 1668, in which he deplores what he perceives as the growing ignorance of his contemporaries. In this text, Casaubon accuses Descartes of deliberately encouraging his readers to make themselves ignorant by urging them to renounce their beliefs and forget all the knowledge that they have previously acquired: ‘a man must first strip himself of all that he has ever known, or believed.’
This accusation against the champion of rationalism may seem paradoxical at first, but it should not come as a complete surprise: if Descartes did not praise ignorance as such, and certainly not as an end in itself, he did encourage his readers to get rid of all their previous opinions, prejudices and false knowledge, as he himself had done after realising the uncertainty of the knowledge he had been taught as a child. Indeed, in the Discourse on Method (1637), Descartes relates how he initially loved philosophy, theology, poetry and mathematics, which he had been taught at the prestigious Collège Royal de La Flèche, before he became aware of the variety of opinions and the pervasiveness of error, which made him doubt all his knowledge and beliefs. In the Meditations (1641), a few years after the Discourse, Descartes further explains that, in the face of such doubt and uncertainty, he decided to get rid of all the opinions he had formed or acquired in order to rebuild science and knowledge on a firm basis. This experience of ‘radical’ or ‘hyperbolical’ doubt, as it has later been called, which results in the rejection of all knowledge, implying a form of self-induced ignorance, was unsurprisingly construed as an extreme stance by 17th-century commentators, and we may understand how it could be interpreted as a promotion of complete ignorance…
[Parageau unpacks Casaubon’s critique…]
… The 17th-century manipulation techniques here described by Casaubon are strikingly similar to what we now call ‘gaslighting’, a form of emotional and psychological abuse that leads the victim to question their own cognitive faculties and sometimes even their very sanity. As a matter of fact, the Dutch scholar and theologian Martin Schoock (1614-1669), Descartes’s contemporary, had, even more clearly than Casaubon and 25 years earlier, accused Descartes’s ‘new philosophy’ of leading to mental disorder, because choosing ignorance, according to Schoock in his Admirable Method (1643), amounts to deliberately putting off the light of reason in one’s mind: ‘A grown man who forgets everything is ignorant of everything, and where there is ignorance of everything, there is mental disorder.’ (My translation.)
As this passage makes clear, Schoock also thought that Descartes’s radical doubt could not but result in complete ignorance – Descartes’s philosophy was therefore a mere tool devised to spread ignorance. This call for radical doubt, as Schoock understood it, was based on the Cartesian idea that certain and evident truth can come only from within oneself. The French philosopher had allegedly ‘waged a war on books and reading’ and encouraged laziness, especially among young people, who were invited to spend all day lying down and ‘meditating’, in other words doing nothing. Descartes’s victims, Schoock adds, were primarily less-educated or naive people, who fell more readily for his deceptive arguments as they were dazzled by his reputation and influence. Indeed, the example of Descartes’s alleged use of ignorance also reveals the insidious domination of the intellectual elite over less-educated people. Thus, for Schoock as for Casaubon, the aim of Descartes’s so-called philosophy was to turn ignorant people into disciples and ensure their obedience.
If we are to believe Casaubon and Schoock, Descartes’s alleged manipulation was fairly successful, and a great number of people joined ‘the Cartesian sect’. So how come Descartes could so easily dupe his contemporaries? One answer might be that his deception did not rely on lying, but on the more strategic use and abuse of doubt. Doubt is indeed more subtle than crude lies, and therefore more efficient, provided the audience who is being manipulated is not entirely ignorant at first (otherwise, lies would work just as well), yet not educated or sagacious enough to be able to detect and expose the deception straight away. The efficiency of doubt as a strategy may also reside in its versatility. Doubt is indeed both an epistemic virtue, or the first step on the path to truth (the philosopher is always initially a doubter, someone who questions what they have been taught or what seems self-evident), and an epistemic vice, as it can lead to destabilisation and even dissolution of truth and knowledge altogether when it is excessive or misplaced…
… The condemnation of Descartes by Casaubon and Schoock should also be seen as the manifestation of a desperate effort to resist change in the intellectual context that led to the emergence of modern science. The conservative Casaubon feared and lamented the coming destruction of traditional knowledge, which he believed was brought forth by an undue insistence on method to the detriment of learning itself. One must admit that Cartesianism is indeed obsessed with method – Descartes’s famous Discourse is evidence enough. Moreover, Descartes’s call for the rejection by each individual of all their knowledge and opinions was not only interpreted as a means to get power over those who would make themselves ignorant, but also as the programmed extinction of established knowledge, which would give way to something new and therefore suspicious. Schoock shared those preoccupations but was probably even more worried about the psychological consequences of Descartes’s philosophy on his followers and the larger public if ever it managed to spread, which he seriously feared because the mere ‘novelty’ of this philosophy made it attractive to the ignorant multitude. Surprising as it may seem, Schoock’s fears about the sanity of Cartesians were not entirely unjustified. Indeed, if the allegation that Descartes deliberately produced ignorance to control people can be easily dismissed, the claim that his philosophy was likely to lead to madness is more convincing.
Most specialists of Descartes’s philosophy have ignored the affective experience described in the Discourse and the Meditations to focus instead on the order of reason in those texts. Radical doubt and the cogito have thus been interpreted as literary and rhetorical devices, or mere fables (the word is used by Descartes himself in the Discourse). They are generally seen as fictions or thought experiments, rather than as a cognitive process that Descartes actually experienced. If the autobiographical and emotional dimension of self-induced ignorance has been neglected so far, it might be because this aspect does not match the overarching interpretation of Cartesianism as the rule of reason. Descartes urged people to reject all their opinions and knowledge only as a temporary precondition to accessing truth, not as a permanent state. But still, he did encourage self-induced ignorance.
The epistemic anxiety that followed was described by Casaubon and Schoock, as mentioned above. But the origin of the search for truth is emotionally charged as well, as it is grounded in disillusionment and existential despair following the discovery that one was taught erroneous opinions as a child and was therefore deceived. This painful discovery gives rise to the need for purification through the rejection of one’s opinions and withdrawal from the world. The emotional impact of the search for truth is attested in Adrien Baillet’s late 17th-century biography of Descartes, which precisely describes Descartes’s physical and psychological distress.
As Tristan Dagron argues in his book Pensée et cliniques de l’identité (2019), or ‘Thoughts and Treatments of Identity’, the experience that Descartes relates in the First Meditation, where he describes the need for the purification of his mind, can be interpreted as a reappropriation of three dreams that he had in November 1619, which left him confused and mentally disturbed as he was confronted with radical doubt about the distinction between dreaming and waking. When he narrates those dreams, Baillet talks of Descartes’s violent agitations, exhaustion, despair and ‘enthusiasm’, some form of divine inspiration and madness (hence also Descartes’s association with religious sects by his opponents). Dagron shows that those dreams were a traumatic experience for Descartes, which is echoed in the First Meditation and its presentation of radical doubt.
The emotionally unsettling confrontation with radical doubt and madness should be acknowledged as the starting point of the search for truth in what is commonly hailed today as a radically rationalist, emotion-free system of thought – perhaps a consequence of Michel Foucault’s influential reading of the Meditations as a violent and successful attempt at muzzling madness, or a ‘coup de force’, in his book Madness and Civilization (1961). Thus, Casaubon and Schoock were right in arguing that radical doubt implied epistemic anxiety and madness, but madness is not rejected by Descartes – on the contrary, it is embraced and then healed, so to speak, by his philosophy. This might actually be the true reason why Descartes is indeed the founder of modern Western science and philosophy…
“The French Liar,” from @sparageau.bsky.social in @aeon.co.
* René Descartes
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As marshall our marbles, we might send magical birthday greetings to John Dee, the mathematician, astronomer, and geographer who was a consultant to Elizabeth I– and who was born on this date in 1527. Dee was a translator of Euclid, and a friend of both Gerardus Mercator and Tycho Brahe; he revolutionized navigation by applying geometry; and he coined the word “Brittannia” and the phrase “British Empire.” He had a tremendous impact on architecture and theater– and was the model for Shakespeare’s Prospero.
“So how come such a significant philosopher– one of very few in a country then considered an intellectual backwater– barely features in British history books? Because of his notorious links with magic” (observed BBC’s Discover). Dee was indeed involved (most heavily, toward the end of his life) in the Hermetic Arts: alchemy, astrology, divination, Hermetic philosophy and Rosicrucianism (the Protestant answer to the Jesuits, which Dee founded). Perhaps most (in)famously, Dee put a hex on the Spanish Armada, a spell widely credited at the time for the misfortunes that befell the Iberian fleet (which readers may recall).
In a way that presaged Isaac Newton, Dee’s work spanned the world’s of science and magic at just the point that those world’s began to separate.
“We must not forget that the wheel is reinvented so often because it is a very good idea”*…
… but when was it first discovered? And, and given its obvious and ubiquitous utility, why there (and not somewhere else)? Kai James offers an answer…
Imagine you’re a copper miner in southeastern Europe in the year 3900 B.C.E. Day after day you haul copper ore through the mine’s sweltering tunnels.
You’ve resigned yourself to the grueling monotony of mining life. Then one afternoon, you witness a fellow worker doing something remarkable.
With an odd-looking contraption, he casually transports the equivalent of three times his body weight on a single trip. As he returns to the mine to fetch another load, it suddenly dawns on you that your chosen profession is about to get far less taxing and much more lucrative.
What you don’t realize: You’re witnessing something that will change the course of history – not just for your tiny mining community, but for all of humanity.
Despite the wheel’s immeasurable impact, no one is certain as to who invented it, or when and where it was first conceived. The hypothetical scenario described above is based on a 2015 theory that miners in the Carpathian Mountains – in present-day Hungary – first invented the wheel nearly 6,000 years ago as a means to transport copper ore.
The theory is supported by the discovery of more than 150 miniaturized wagons by archaeologists working in the region. These pint-sized, four-wheeled models were made from clay, and their outer surfaces were engraved with a wickerwork pattern reminiscent of the basketry used by mining communities at the time. Carbon dating later revealed that these wagons are the earliest known depictions of wheeled transport to date.
This theory also raises a question of particular interest to me, an aerospace engineer who studies the science of engineering design. How did an obscure, scientifically naive mining society discover the wheel, when highly advanced civilizations, such as the ancient Egyptians, did not?…
Read on to find out: “How was the wheel invented? Computer simulations reveal the unlikely birth of a world-changing technology nearly 6,000 years ago,” from @us.theconversation.com.
* “We must not forget that the wheel is reinvented so often because it is a very good idea; I’ve learned to worry more about the soundness of ideas that were invented only once.” – David Parnas
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As we roll along, we might we might send a “Alles Gute zum Geburtstag” to man at the center of the question of the invention of another foundational “technology”: the polymathic Gottfried Wilhelm Leibniz, the philosopher, mathematician, inventor (of, among other things, an early calculator) and political adviser.
Leibnitz was important both as a metaphysician and as a logician, but who is probably best remembered for his independent invention of the calculus; he was born on this date in 1646. Leibniz independently discovered and developed differential and integral calculus, which he published in 1684; but he became involved in a bitter priority dispute with Isaac Newton, whose ideas on the calculus were developed earlier (1665), but published later (1687). Scholars largely agree that, in fact, Leibnitz and Newton independently developed “the greatest advance in mathematics that had taken place since the time of Archimedes.”
“Great minds think alike”*…
Brian Potter on the (perhaps surprising) frequency with which “heroic” inventors are in fact better understood as the winners of close races…
When Alexander Graham Bell filed a patent for the telephone on February 14th, 1876, he beat competing telephone developer Elisha Gray to the patent office by just a few hours. The resulting legal dispute between Bell Telephone and Western Union (which owned the rights to Gray’s invention) would consume millions of dollars before being resolved in Bell’s favor in 1879.
Such cases of multiple invention are common, and some of the most famous and important modern inventions were invented in parallel. Both Thomas Edison and Joseph Swan patented incandescent lightbulbs in 1880. Jack Kilby and Robert Noyce patented integrated circuits in 1959. Hans von Ohain and Frank Whittle independently invented the jet engine in the 1930s. In a 1922 paper, William Ogburn and Dorothy Thomas documented 150 cases of multiple discovery in science and technology. Robert Merton found 261 examples in 1961, and observed that the phenomenon of multiple discovery was itself a multiple discovery, having been described over and over again since at least the early 19th century.
But exactly how common is multiple invention? The frequency of examples suggests that it can’t be particularly rare, but that doesn’t tell us the rate at which it occurs. In “How Common is Independent Discovery?,” Matt Clancy catalogues several attempts to estimate the frequency of multiple discovery, and tentatively comes up with a frequency of around 2-3% for simultaneous scientific discoveries, and perhaps an 8% chance that a given invention will be reinvented in the next decade. But the evidence for inventions is somewhat inconsistent, and varies greatly between studies. Clancy estimates a reinvention rate of around 8% per decade, but another study he found that looked at patent interference lawsuits between 1998 and 2014 suggests an independent invention rate of only around 0.02% per year.
The frequency of multiple invention is a useful thing to know, because it can give us clues about the nature of technological progress. A very low rate of multiple invention suggests that progress might be driven by a small number of “genius” inventors (what we might call the Great Man Theory of technological progress), and that it might be highly historically contingent (if you re-rolled the dice of history, maybe you get a totally new set of inventions and a different technological palette). A high rate of multiple invention suggests that progress is more a function of broad historical forces (that inventions appear when the conditions are right), and that progress is less contingent (if you re-rolled the dice of history, you’d get a similar progression of inventions). And if the rate of multiple invention is changing over time, perhaps the nature of technological progress is changing as well…
[Potter reviews the history and concludes that “multiple invention was extremely common”…]
… My main takeaway is that the ideas behind inventions are often in some sense “obvious,” or at least not so surprising or unexpected that many people won’t think of them. In some cases, this is probably because once some new possibility comes along, lots of people think of similar things that could be done with it. Once the properties of electricity began to be understood, many people came up with the idea of using it to send signals (telephone, telegraph), or to create motion (engines and generators), or to generate light (arc lamps, incandescent lights). Once the steam engine came along, lots of people had the idea to use it to power various types of vehicles.
In other cases, multiple invention probably occurs because important problems will attract many people trying to solve them. Steel corrosion was a large problem inspiring many folks to look for ways to create a steel that didn’t rust, or notice the potential value if they stumbled across such a material. Lamps causing mine fires were a major problem, inspiring many people to come up with ideas for safety lamps. The smoke produced by gunpowder was a major problem, inspiring many efforts to develop smokeless powders. And because would-be inventors will all draw from the same pool of available technologies, materials, and capabilities when coming up with a solution, there will be a large degree of convergence in the solutions they come up with…
Fascinating: “How Common is Multiple Invention?” from @const-physics.blogsky.venki.dev.
* common idiom
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As we reconsider credit, we might recall that it was on this date in 1661 that Isaac Newton— a key figure in the Scientific Revolution and the Enlightenment that followed– entered Trinity College, Cambridge. Soon after Newton obtained his BA degree at Cambridge in August 1665, the university temporarily closed as a precaution against the Great Plague. Although he had been undistinguished as a Cambridge student, his private studies and the years following his bachelor’s degree have been described as “the richest and most productive ever experienced by a scientist.”
Relevantly to the piece above, Newton was party to a dispute with Gottfried Wilhelm Leibniz (who started, at age 14, at the University of Leipzig the same year that Newton matriculated at Cambridge) over which of them developed calculus– called “the greatest advance in mathematics that had taken place since the time of Archimedes.” The modern consensus is that the two men independently developed their ideas.
“Truth is ever to be found in the simplicity, and not in the multiplicity and confusion of things”*…
From Kim (Scott) Morrison‘s and Dror Bar-Natan‘s, The Knot Atlas, “a complete user-editable knot atlas, in the wiki spirit of Wikipedia“– a marvelous example of a wide-spread urge in mathematics to find order through classification. As Joseph Howlett explains, that quest continues, even as it proves vexatious…
Biology in the 18th century was all about taxonomy. The staggering diversity of life made it hard to draw conclusions about how it came to be. Scientists first had to put things in their proper order, grouping species according to shared characteristics — no easy task. Since then, they’ve used these grand catalogs to understand the differences among organisms and to infer their evolutionary histories. Chemists built the periodic table for the same purpose — to classify the elements and understand their behaviors. And physicists made the Standard Model to explain how the fundamental particles of the universe interact.
In his book The Order of Things, the philosopher Michel Foucault describes this preoccupation with sorting as a formative step for the sciences. “A knowledge of empirical individuals,” he wrote, “can be acquired only from the continuous, ordered and universal tabulation of all possible differences.”
Mathematicians never got past this obsession. That’s because the menagerie of mathematics makes the biological catalog look like a petting zoo. Its inhabitants aren’t limited by physical reality. Any conceivable possibility, whether it lives in our universe or in some hypothetical 200-dimensional one, needs to be accounted for. There are tons of different classifications to try — groups, knots, manifolds and so on — and infinitely many objects to sort in each of those classifications. Classification is how mathematicians come to know the strange, abstract world they’re studying, and how they prove major theorems about it.Take groups, a central object of study in math. The classification of “finite simple groups” — the building blocks of all groups — was one of the grandest mathematical accomplishments of the 20th century. It took dozens of mathematicians nearly 100 years to finish. In the end, they figured out that all finite simple groups fall into three buckets, except for 26 itemized outliers. A dedicated crew of mathematicians has been working on a “condensed” proof of the classification since 1994 — it currently comprises 10 volumes and several thousand pages, and still isn’t finished. But the gargantuan undertaking continues to bear fruit, recently helping to prove a decades-old conjecture that you can infer a lot about a group by examining one small part of it.
Mathematics, unfettered by the typical constraints of reality, is all about possibility. Classification gives mathematicians a way to start exploring that limitless potential…[Howlett reviews attempts to classify numbers by “type” (postive/negative, rational/irrational), and mathematical objects by “equivalency” (shapes that can be stretched or squeezed into the other without breaking or tearing, like a doughnut and and coffee cup (see here)…]
… Similarly, classification has played an important role in knot theory. Tie a knot in a piece of string, then glue the string’s ends together — that’s a mathematical knot. Knots are equivalent if one can be tangled or untangled, without cutting the string, to match the other. This mundane-sounding task has lots of mathematical uses. In 2023, five mathematicians made progress on a key conjecture in knot theory that stated that all knots with a certain property (being “slice”) must also have another (being “ribbon”), with the proof ruling out a suspected counterexample. (As an aside, I’ve often wondered why knot theorists insist on using nouns as adjectives.)
Classifications can also get more meta. Both theoretical computer scientists and mathematicians classify problems about classification based on how “hard” they are.
All these classifications turn math’s disarrayed infinitude into accessible order. It’s a first step toward reining in the deluge that pours forth from mathematical imaginings…
“The Never-Ending Struggle to Classify All Math,” from @quantamagazine.bsky.social.
* Isaac Newton
###
As we sort, we might spare a thought for the author of our title quote, Sir Isaac Newton; he died in this date in 1727. A polymath, Newton excelled in– and advanced– mathematics, physics, and astronomy; he was a theologian and a government offical (Master of the Mint)… and a dedicated alchemist. He was key to the Scientific Revolution and the Enlightenment that followed.
Newton’s book Philosophiæ Naturalis Principia Mathematica (Mathematical Principles of Natural Philosophy), first published in 1687, achieved the first great unification in physics and established classical mechanics (e.g., the Laws of Motion and the principle of universal gravitation). He also made seminal contributions to optics, and shares credit with German mathematician Gottfried Wilhelm Leibniz for formulating infinitesimal calculus. Indeed, Newton contributed to and refined the scientific method to such an extent that his work is considered the most influential in the development of modern science.
“There is only one world, the natural world, exhibiting patterns we call the ‘laws of nature’”*…
The quote above (in full, below) is the reigning substantive understanding of scientific naturalism that is commonplace today. Indeed, the modern era is often seen as the triumph of science over supernaturalism. But, as Peter Harrison explains, what really happened is far more interesting…
By any measure, the scientific revolution of the 17th century was a significant milestone in the emergence of our modern secular age. This remarkable historical moment is often understood as science finally liberating itself from the strictures of medieval religion, striking out on a new path that eschewed theological explanations and focused its attentions solely on a disenchanted, natural world. But this version of events is, at best, half true.
Medieval science, broadly speaking, had followed Aristotle in seeking explanations in terms of the inherent causal properties of natural things. God was certainly involved, at least to the extent that he had originally invested things with their natural properties and was said to ‘concur’ with their usual operations. Yet the natural world had its own agency. Beginning in the 17th century, the French philosopher and scientist René Descartes and his fellow intellectual revolutionaries dispensed with the idea of internal powers and virtues. They divested natural objects of inherent causal powers and attributed all motion and change in the universe directly to natural laws.
But, for all their transformative influence, key agents in the scientific revolution such as Descartes, Johannes Kepler, Robert Boyle and Isaac Newton are not our modern and secular forebears. They did not share our contemporary understandings of the natural or our idea of ‘laws of nature’ that we imagine underpins that naturalism…
[Harrison traces the history of the often contentious, but ultimately momentous rise of naturalism, then considers the historical acounts of that ascension– and what they gloss over or miss altogether. He then turns to whay that matters…]
… the contrived histories of naturalism that purport to show its victory over supernaturalism were fabricated in the 19th century and are simply not consistent with the historical evidence. They are also tainted by a cultural condescension that, in the past at least, descended into outright racism. Few, if any, would today endorse the chauvinism that attends these older, triumphalist accounts of the history of naturalism. Yet, it is worth reflecting upon the extent to which elements of cultural condescension necessarily colour scholarly endeavours that are premised on the imagined ‘neutral’ grounds of naturalism. Careful consideration of the contingent historical circumstances that gave rise to present analytic categories that enjoy significant standing and authority would suggest that there is nothing especially neutral or objective about them. Any clear-eyed crosscultural comparison – one that refrains from assessing worldviews in terms of how they measure up to the standard of the modern West – will reinforce this. We might go so far as to adopt a form of ‘reverse anthropology’, where we think how our own conceptions of the world might look if we adopted the frameworks of others. This might entail dispensing with the idea of the supernatural, and attempting to think outside the box of our recently inherited natural/supernatural distinction.
History [that is, the “actual” history that Harrison recounts] suggests that our regnant modern naturalism is deeply indebted to monotheism, and that its adherents may need to abandon the comforting idea that their naturalistic commitments are licensed by the success of science. As for the idea of the supernatural, ironically this turns out to be far more important for the identity of those who wish to deny its reality than it had ever been for traditional religious believers…
Fascinating and provocative: “The birth of naturalism,” from @uqpharri in @aeonmag.
* “There is only one world, the natural world, exhibiting patterns we call the ‘laws of nature’, and which is discoverable by the methods of science and empirical investigation. There is no separate realm of the supernatural, spiritual, or divine; nor is there any cosmic teleology or transcendent purpose inherent in the nature of the universe or in human life.” – Sean Carroll, The Big Picture
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As we rethink reality, we might recall that it was on this date in 1588 that Tycho Brahe first outlined his “Tychonic system” concept of the structure of the solar system. The Tychonic system was a hybrid, sharing both the basic idea of the geocentric system of Ptolemy, and the heliocentric idea of Nicholas Copernicus. Published in his De mundi aethorei recentioribus phaenomenis, Tycho’s proposal, retaining Aristotelian physics, kept the the Sun and Moon revolving about Earth in the center of the universe and, at a great distance, the shell of the fixed stars was centered on the Earth. But like Copernicus, he agreed that Mercury, Venus, Mars, Jupiter, and Saturn revolved about the Sun. Thus he could explain the motions of the heavens without “crystal spheres” carrying the planets through complex Ptolemaic epicycles.
On this same date, in 1633, Galileo Galilei arrived in Rome to face trial before the Inquisition. His crime was professing the belief that the earth revolves around the sun– based on observations that he’d made further to Copernicus and Tycho.
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