Category Archives: Myths of Science

The West’s intellectual birthright!

The American cultural magazine, The Atlantic recently published an article by Daniel Foster entitled, In Defense of ‘The West’. This was a political article questioning the speech that Donald Trump had made in Warsaw and what the author sees, as what The Trump White means when they talk of ‘The West’. Amongst many other things the article contains the following paragraph encapsulating the authors view of what he sees as The West’s intellectual birthright in the history of science:

Likewise, Egypt hosted the first great repository of Western knowledge—the library at Alexandria—and for a millennium or so following that library’s destruction, it was Muslim metaphysicians who kept lit the flame of Greek ideas. The West’s intellectual birthright, then, was reborn in Latin and French and German and English because it was vouchsafed in Arabic, in the dark interregnum between Charlemagne and the Renaissance.

These sixty-six words made my hair stand on end, or would have done if I had any, for several different reasons that I shall attempt to explicate in what follows.

We will start off with the expression The West’s intellectual birthright. What is meant here is of course Greek science, which doesn’t actually exist and never did. However, how is Greek science The West’s intellectual birthright? The article’s author is trying to argue against a view of the West as being white and bordering the North Atlantic and he could start right here. Even the Greek’s were quite happy to admit that their scientific endeavours were based on those of their predecessors in Egyptian and Babylon, whereby Babylon is shorthand for the various cultures that occupied the so-called fertile crescent in antiquity. So why is Greek science not the intellectual birthright of North Africa or the Middle East, the areas that laid its foundations? Greek science is nobody’s intellectual birthright; the various schools of intellectual thought who developed scientific and proto-scientific ideas within Greek culture in the period between roughly 600 BCE and 600 CE sowed seeds in various cultures throughout the world some of which blossomed and some of which withered and the cumulative developments out of those seeds belong to the whole of humanity.

The author tries to argue against a white North Atlantic West by pointing out that it is geographically and culturally intertwined with much outside of this narrow concept viewed historically and so the opening sentence of the paragraph is supposed to imply a non European source for that intellectual birthright. This ignores the fact that although Alexandria lies in Egypt it was a Greek city and the library was a Greek institution and not an Egyptian one. The next problem is that the library in Alexandria was not the first, and by no means the only, great repository of Western knowledge and was not in any meaningful sense destroyed but declined over several centuries probably disappearing from the world stage around 300 CE. For full details of this story I direct you to Tim O’Neill’s recent excellent essay on the subject.

We now stumble over the next problem; Muhammad first fled from Mecca to Medina in 622 CE, this being the formal date of the establishment of Islam. The establishment of Islam as an intellectual culture begins first in the 8th century CE, so more than 400 years after the final collapse of the library of Alexandria. The Muslims, Christians, Jews and Zoroastrians who established the intellectual culture within the Islamic Empire collected their science and philosophy not only from various Greek sources but also from Persian, Indian and Chinese ones, so they are not just keeping the flame of Greek ideas lit but a melange of ideas from numerous sources. Even more important, they didn’t just keep a flame lit but analysed, criticised, commented upon and improved and expanded the knowledge that they had collected from those other cultures. They were not simply guardians of the flame but added fuel of their own to make it burn brighter.

This knowledge came back into Europe through the boundaries between the Islamic Empire and Christian Europe in Spain and Sicily in the 12th and 13th centuries through the efforts of the so-called translators. These were Christian scholars who worked together with Arabs and Jews to translate the Greek, Latin and Arabic works from Arabic into Latin. This means that the Islamic Empire had only had ‘exclusive’ access to this conglomeration of knowledge for five hundred years and not a millennium as claimed above. Note that this knowledge returned to Europe only in Latin and not also in French German and English as claimed. The introduction of the use of the vernacular for scientific texts only really began in the seventeenth century long after this knowledge had become established in Europe.

We now turn to the final and by far and away the worst piece of shoddy history in this strange paragraph, its final clause: in the dark interregnum between Charlemagne and the Renaissance. When I read this the first time I did more than a double take. I seriously couldn’t believe what I had just read. Let us be clear. We are not talking here about the Early Middle Ages, long known as The Dark Ages, a term that historians now shun but about the period that represents the emergence from the Early Middle Ages into what is generally known as the High Middle Ages and this is according to our author a ‘dark interregnum’. Sorry but this is just simple wrong.

There was a definable intellectual decline within the Roman Empire that begins gradually in the middle of the 2nd century CE and can be regarded as complete by around 400 CE with the collapse of the Western Empire. Over the next approximately 400 years there is little of no intellectual activity in Europe and it is first with Karl der Große (that’s Charlemagne) and the so-called Carolinian Renaissance that this situation begins to change. Far from being the start of a dark interregnum Charlemagne marks the end of one and the gradual climb out of the intellectual darkness into the sunshine of knowledge. Starting with Charlemagne’s own intellectual reformer, Alcuin of York, there is a long chain of medieval scholars including the translators mentioned above, the Oxford Calculatores, the Paris Physicists and many others who laid the foundations for the Renaissance and the so-called Scientific Revolution.

The rich world of medieval science and technology has been well documented beginning with the work of Pierre Duhem in the 19th and early 20th centuries over the substantial contributions of Alistair Crombie, Marshall Clagett, Edward Grant, John Murdoch, Toby Huff and David Lindberg amongst others. With the work of James Hannam and John Freely there are even two good popular books on the subject available for those who don’t want to plough through heavy academic texts, so there is really no excuse for the piece of arrant bullshit presented by Daniel Foster.

The scant paragraph that I have eviscerated above is unfortunately typical for the type of history of science, although to even call it history is a misnomer, that gets presented all too often by journalists, a collection of random myths, legends, clichés and ignorance that they have picked up somewhere down the line. Checking their facts or even consulting an expert on the subject seems to be too much trouble for these people, what does it matter, it’s just history of science seems to be their creed and that really pisses me off.


Filed under Myths of Science

Did Eratosthenes really measure the size of the earth?

Last Thursday was Summer Solstice in the Northern Hemisphere and The Guardian chose to mark the occasion with an article by astrophysicist turned journalist and novelist, Stuart Clark, who chose to regale his readers with a bit of history of science. The big question was would he get it right? He has form for not doing so and in fact, he succeeded in living up to that form. His article entitled Summer solstice: the perfect day to bask in a dazzling scientific feat, recounted the well know history of geodesy tale of how Eratosthenes used the summer solstice to determine the size of the earth.

Eratosthenes of Cyrene was the chief librarian at the great library of Alexandria in the third century BC. So the story goes, he read in one of the library’s many manuscripts an account of the sun being directly overhead on the summer solstice as seen from Syene (now Aswan, Egypt). This was known because the shadows disappeared at noon, when the sun was directly overhead. This sparked his curiosity and he set out to make the same observation in Alexandria. On the next solstice, he watched as the shadows grew small – but did not disappear, even at noon.

The length of the shadows in Alexandria indicated that the sun was seven degrees away from being directly overhead. Eratosthenes realised that the only way for the shadow to disappear at Syene but not at Alexandria was if the Earth’s surface was curved. Since a full circle contains 360 degrees, it meant that Syene and Alexandria were roughly one fiftieth of the Earth’s circumference away from each other.

Knowing that Syene is roughly 5000 stadia away from Alexandria, Eratosthenes calculated that the circumference of the Earth was about 250,000 stadia. In modern distance measurements, that’s about 44,000km – which is remarkably close to today’s measurement of 40,075km.

Eratosthenes also calculated that the tilt of the Earth’s polar axis (23.5 degrees) is why we have the solstice in the first place.

Illustration showing a portion of the globe showing a part of the African continent. The sunbeams shown as two rays hitting the ground at Syene and Alexandria. Angle of sunbeam and the gnomons (vertical pole) is shown at Alexandria, which allowed Eratosthenes’ estimates of radius and circumference of Earth.
Source: Wikimedia Commons

Whilst it is correct that Eratosthenes was chief librarian of the Alexandrian library one should be aware that the Mouseion (Shrine of the Muses, the origin of the modern word, museum), which housed the library was more akin to a modern academic research institute than what one envisages under the word library. Eratosthenes was according to the legends a polymath, astronomer, cartographer, geographer, mathematician, poet and music theorist.

From the information that during the summer solstice the sun was directly overhead in Syene at noon, and cast no shadows and that a gnomon in Alexandria 5000 stadia north of Syene did cast a shadow, Eratosthenes did not, and I repeat did not, realise that the Earth’s surface was curved. Eratosthenes knew that the Earth’s surface was curved, as did every educated Greek scholar in the third century BCE. Sometimes I get tired of repeating this but the first to realise that the Earth was a sphere were the Pythagoreans in the sixth century BCE. Aristotle had summarised the empirical evidence that showed that the Earth is a sphere in the fourth century BCE, in writings that Eratosthenes, as chief librarian in Alexandria, would have been well acquainted with. Put simply, Eratosthenes knew that he could, using trigonometry, calculate the diameter of the Earth’s sphere with the data he had accumulated, because he already knew that it was a sphere.

The next problem with the account given here is one that almost always turns up in popular version of the Eratosthenes story; there wasn’t just one measure of length in the ancient Greek world known as a stadium but quite a collection of different ones, all differing in length, and we have absolutely no idea which one is meant here. It is in the end not so important as all of them give a final figure with 17% or less error compared to the true value, which is for the method used quite a reasonable ball park figure for the size of the Earth. However this point is one that should be mentioned when recounting the Eratosthenes story. Eratosthenes may or may not have calculated the tilt of the Earth’s axis but this is of no real historical significance, as the obliquity of the ecliptic, as it is also known, was, like the spherical shape of the Earth, known well before his times.

An astute reader might have noticed that above I used the expression, according to the legends, when describing Eratosthenes’ supposed talents. The problem is that everything we know about Eratosthenes is hearsay. None of his alleged many writings have survived. We only have second hand reports of his supposed achievements, most of them centuries after he lived. This raises the question, how reliable are these reports? A comparable situation is the so-called theorem of Pythagoras, well known to other cultures well before Pythagoras lived and only attributed to him long after he had died.

The most extreme stance is elucidated by historian of astronomy, John North, in his one volume history of astronomy, Cosmos:

None of Eratosthenes’ writings survive, however, and some have questioned whether he ever found either the circumference of the Earth, or – as is often stated – the obliquity of the ecliptic, on the basis of measurements.

So what is our source for this story? The only account of Eratosthenes’ measurement comes from the book On the Circular Motions of the Celestial Bodies by the Greek astronomer Cleomedes and with that the next problems start. It is not actually known when Cleomodes lived. On the basis of his writings Thomas Heath, the historian of Greek mathematics, thought that text was written in the middle of the first century BCE. However, Otto Neugebauer, historian of ancient science, thought that On the Circular Motions of the Celestial Bodies was written around 370 CE. Amongst historians of science the debate rumbles on. North favours the Neugebauer date, placing the account six centuries after Eratosthenes’ death. What exactly did Cleomodes say?

The method of Eratosthenes depends on a geometrical argument and gives the impression of being slightly more difficult to follow. But his statement will be made clear if we premise the following. Let us suppose, in this case too, first, that Syene and Alexandria he under the same meridian circle, secondly, that the distance between the two cities is 5,000 stades; 1 and thirdly, that the rays sent down from different parts of the sun on different parts of the earth are parallel; for this is the hypothesis on which geometers proceed Fourthly, let us assume that, as proved by the geometers, straight lines falling on parallel straight lines make the alternate angles equal, and fifthly, that the arcs standing on (i e., subtended by) equal angles are similar, that is, have the same proportion and the same ratio to their proper circles—this, too, being a fact proved by the geometers. Whenever, therefore, arcs of circles stand on equal angles, if any one of these is (say) one-tenth of its proper circle, all the other arcs will be tenth parts of their proper circles.

Any one who has grasped these facts will have no difficulty in understanding the method of Eratosthenes, which is this Syene and Alexandria lie, he says, under the same mendian circle. Since meridian circles are great circles in the universe, the circles of the earth which lie under them are necessarily also great circles. Thus, of whatever size this method shows the circle on the earth passing through Syene and Alexandria to be, this will be the size of the great circle of the earth Now Eratosthenes asserts, and it is the fact, that Syene lies under the summer tropic. Whenever, therefore, the sun, beingin the Crab at the summer solstice, is exactly in the middle of the heaven, the gnomons (pointers) of sundials necessarily throw no shadows, the position of the sun above them being exactly vertical; and it is said that this is true throughout a space three hundred stades in diameter. But in Alexandria, at the same hour, the pointers of sundials throw shadows, because Alexandria lies further to the north than Syene. The two cities lying under the same meridian great circle, if we draw an arc from the extremity of the shadow to the base of the pointer of the sundial in Alexandria, the arc will be a segment of a great circle in the (hemispherical) bowl of the sundial, since the bowl of the sundial lies under the great circle (of the meridian). If now we conceive straight lines produced from each of the pointers through the earth, they will meet at the centre of the earth. Since then the sundial at Syene is vertically under the sun, if we conceive a straight line coming from the sun to the top of the pointer of the sundial, the line reaching from the sun to the centre of the earth will be one straight line. If now we conceive another straight line drawn upwards from the extremity of the shadow of the pointer of the sundial in Alexandria, through the top of the pointer to the sun, this straight line and the aforesaid straight line will be parallel, since they are straight lines coming through from different parts of the sun to different parts of the earth. On these straight lines, therefore, which are parallel, there falls the straight line drawn from the centre of the earth to the pointer at Alexandria, so that the alternate angles which it makes arc equal. One of these angles is that formed at the centre of the earth, at the intersection of the straight lines which were drawn from the sundials to the centre of the earth; the other is at the point of intersection of the top of the pointer at Alexandria and the straight line drawn from the extremity of its shadow to the sun through the point (the top) where it meets the pointer. Now on this latter angle stands the arc carried round from the extremity of the shadow of the pointer to its base, while on the angle at the centre of the earth stands the arc reaching from Syene to Alexandria. But the arcs are similar, since they stand on equal angles. Whatever ratio, therefore, the arc in the bowl of the sundial has to its proper circle, the arc reaching from Syene to Alexandria has that ratio to its proper circle. But the arc in the bowl is found to be one-fiftieth of its proper circle.’ Therefore the distance from Syene to Alexandria must necessarily be one-fiftieth part of the great circle of the earth. And the said distance is 5,000 stades; therefore the complete great circle measures 250,000 stades. Such is Eratosthenes’ method. (This is Thomas Heath’s translation) 

You will note that Cleomedes makes no mention of Eratosthenes determining the spherical shape of the Earth through his observations but writes very clearly of great circles on the globe, an assumption of spherical form. So where does Stuart Clark get this part of his story? In his article he tells us his source:

I first heard the story when it was told by Carl Sagan in his masterpiece TV series, Cosmos.

The article has a video of the relevant section of Sagan’s Cosmos and he does indeed devote a large part of his version of the story to explaining how Eratosthenes used his observations to determine that the Earth is curved. In other words Stuart Clark is just repeating verbatim a story, which Carl Sagan, and or his scriptwriters, made up in 1980 without taken the trouble to verify the accuracies or even the truth of what he saw more than thirty years ago. Carl Sagan said it, so it must be true. I have got into trouble on numerous occasions by pointing out to Carl Sagan acolytes that whatever his talents as a science communicator/populariser, his history of science was to put it mildly totally crap. Every week he pumped his souped-up versions of crappy history of science myths into millions of homes throughout the world. In one sense it is only right that Neil deGasse Tyson presented the modern remake of Cosmos, as he does exactly the same.



Filed under History of Astronomy, History of Mathematics, Myths of Science

The True Story of a Lone Genius Who Solved the Greatest Scientific Problem of His Time

The title of this post is the subtitle of Dava Sobel’s Longitude, her mega bestselling account of the life and work of the eighteenth-century clock maker John Harrison; probably the biggest selling popular #histSTM book of all time.

I’m quite happy to admit that when I first read it I was very impressed by her account of a man I didn’t know from a period of history with which I was not particularly well acquainted. However, because I was very impressed, I went looking for more information about the history of John Harrison and the marine chronometer. I found and read quite a lot of academic literature on both topics and came to the realisation that Sobel’s account was not really the true story and that she had twisted the facts to make for a more exciting story but quite far removed from the true narrative.

P.L. Tassaert’s half-tone print of Thomas King’s original 1767 portrait of John Harrison, located at the Science and Society Picture Library, London
Source: Wikimedia Commons

The next segment of the subtitle is also not true. Harrison was supported and encouraged in his endeavours by George Graham, possibly the greatest eighteenth-century English clockmaker, and James Short, almost certainly the greatest telescope maker in the world in the eighteenth century. Both men were important and highly influential figures in the scientific and technological communities of the period. Their support of Harrison rather gives the lie to the claim that Harrison was a lone genius.

George Graham
Source: Wikimedia Commons

The final segment of the subtitle is also highly inaccurate. The problem that Harrison and others were working on in the eighteenth century was a reliable method of determining longitude at sea. They were trying to solve a technological problem not a scientific one. The scientific problem had already been solved in antiquity. Scholars in ancient Greece already knew that to determine the difference in longitude between two locations, one ‘merely’ had to determine the local time difference between them; knowing this the problem was how to determine that time difference, as I said a technological problem.

In antiquity and up to the early modern period cartographers and astronomers (usually the same person) used astronomical phenomena such as solar or lunar eclipses. Observers determined the local time of the occurrence of a given astronomical phenomenon at two different locations and it was then possible to determine their longitudinal difference. Unfortunately eclipses are not very frequent occurrences and so this method has rather limited usefulness. Something else had to be developed.

In the early seventeenth century both Galileo Galilei and Simon Marius discovered the four largest moons of Jupiter and Galileo realised that the orbits of these moons and their appearances and disappearances as the circled Jupiter could, if tabulated accurately enough, be used as a clock to determine longitude. Towards the end of the seventeenth century Giovanni Domenico Cassini and Ole Rømer succeeded in producing the necessary tables and Galileo’s idea could be put into practice. Whilst this method was very successful for cartographers on land, on a rolling ship it was not possible to observe the Jupiter moons accurately enough with a telescope to be able to apply this method; something else had to be used.

The two solutions that came to be developed in the eighteenth century and form the backbone of Sobel’s book, the lunar distance method (lunars) and the marine chronometer, were both first suggested in the sixteenth century, the former by Johannes Werner and the latter by Gemma Frisius. Other methods were suggested but proved either impractical or downright impossible. For lunars you need accurate lunar orbit tables and an accurate instrument to determine the position of the moon. Tobias Mayer provided the necessary tables and John Hadley the instrument with his sextant. For the clock method you require a clock that has a high level of accuracy over a long period of time and which retains that accuracy under the often very adverse conditions of a sea voyage; this is the technological problem that Harrison solved. Sobel presents the two methods as in competition but for navigators they are in fact complimentary and they were both used. As my #histsci soul sister Rebekah ‘Becky’ Higgitt constantly repeats, with the marine chronometer you can carry longitude with you, but if you chronometer breaks down you can’t find it, whereas with lunars you can find longitude, as James Cook did in fact do on one of his voyages.

As I said above, I began to seriously doubt the veracity of Sobel’s account through my own study of the academic accounts of the story, these doubts were then confirmed as I began to follow the blog of the Longitude Board research project set up by Cambridge University and the Maritime Museum in Greenwich, of which Becky Higgitt was one of the lead researchers. For a more balanced and accurate account of the story I recommend Finding Longitude the book written by Becky and Richard Dunn to accompany the longitude exhibition at the Maritime Museum, one of the products of the research project.

Recently I have become fully aware of another aspect of the Harrison story that Sobel does not cover. I say fully aware because I already knew something of it before reading David S. Landes’ excellent Revolution in Time: Clocks and the making of the Modern World (Harvard University Press, 1983). Landes covers the whole history of the mechanical clock from the Middle Ages through to the quartz wristwatch. One of his central themes is the increasing accuracy of clocks down the ages in which the invention of the marine chronometer played a central role, so he devotes a whole chapter to Harrison’s endeavours.

Landes quite correctly points out that after a lifetime of experimentation and ingenious invention John Harrison did indeed produce a solution to the technological problem of determining longitude with a clock. An astute reader with a feel for language might have noticed that in the previous sentence I wrote ‘a solution’ and not ‘the solution’ and therein lies the rub. Over the years that he worked on the problem Harrison produced many ingenious innovations in clock making in order to achieve his aim, an accurate, reliable, highly durable timepiece, however the timepiece that he finally produced was too complex and too expensive to be practicable for widespread everyday service at sea. Harrison had, so to speak, priced himself out of the market.

Harrison’s “Sea Watch” No.1 (H4), with winding crank
Source: Wikimedia Commons

Harrison was by no means the only clock maker working on a viable marine chronometer in the eighteenth century and it is actually his competitors who in the end carried away the laurels and not Harrison. Two clockmakers who made important contributions to the eventual development of a mechanically and financially viable marine chronometer were the Frenchman Pierre Le Roy and Swiss Ferdinand Berthoud, who were bitter rivals.

Pierre Le Roy (1717–1785)
Source: Wikimedia Commons

Plans of Le Roy chronometer
Source: Wikimedia Commons

Ferdinand Berthoud (1727–1807)
Source: Wikimedia Commons

Berthoud marine clock no.2, with motor spring and double pendulum wheel, 1763
Source: Wikimedia Commons

Neither of them can be said to have solved the problem but the work of both of them in different ways led in the right direction. Another contributor was George Graham’s one time apprentice, Thomas Mudge, his highly praised marine chronometer suffered from the same problem as Harrison’s too complex and thus too expensive to manufacture.

The two English clock makers, who actually first solved the problem of a viable marine chronometer were John Arnold and Thomas Earnshaw, who also became bitter rivals. This rivalry involved accusations of theft of innovations and disputes over patents. In the end it was John Arnold and Thomas Earnshaw, who became the most successful of the early clock makers, who worked on the development of the marine chronometer.

Chronometer-maker John Arnold (1736–1799) (attributed to Mason Chamberlin, ca. 1767)
Source: Wikimedia Commons

Thomas Earnshaw (!749–1829)
Source: Wikimedia Commons

Earnshaw chronometer No. 506
Source: Wikimedia Commons

I don’t intend to go into the details of which innovations in clock manufacture each of the man listed above contributed to the development of the marine chronometer that would go on to become an essential navigation tool in the nineteenth century. What I wish to make clear is exactly the same point as my essay on the history of the reflecting telescope for AEON made. From its first conception by Gemma Frisius in the sixteenth century, through the failure of Christiaan Huygens to realise it with his pendulum clock in the late seventeenth century (not discussed here), over its first successful realisation by John Harrison and on to the creation of a viable model by a succession of eighteenth-century clock makers, the marine chronometer was not the product of a single man’s (John Harrison’s) genius but a tool that evolved through the endeavours of a succession of dedicated inventors and innovators. Scientific and technological progress is teamwork.


Filed under History of Navigation, History of Technology, Myths of Science

Why doesn’t he just shut up?

Neil deGrasse Tyson (NdGT), probably the most influential science communicator in the world, spends a lot of time spouting out the message that learning science allows you to better detect bullshit, charlatans, fake news etc. etc. However it apparently doesn’t enable you to detect bullshit in the history of science, at least judging by NdGT’s own record on the subject. Not for the first time, I was tempted recently to throw my computer through the window upon witnessing NdGT pontificating on the history of science.

On a recent video recorded for Big Think, and also available on Youtube and already viewed by 2.6 million sycophants, he answers the question “Who’s the greatest physicist in history?” His answer appears under the title My Man, Sir Isaac Newton. Thoughtfully, Big Think have provided a transcription of NdGT’s blathering that I reproduce below for your delectation before I perform a Hist_Sci Hulk autopsy upon it.

Question: Who’s the greatest physicist in history?DeGrasse Tyson:    Isaac Newton.  I mean, just look… You read his writings.  Hair stands up… I don’t have hair there but if I did, it would stand up on the back of my neck.  You read his writings, the man was connected to the universe in ways that I never seen another human being connected.  It’s kind of spooky actually.  He discovers the laws of optics, figured out that white light is composed of colors.  That’s kind of freaky right there.  You take your colors of the rainbow, put them back together, you have white light again.  That freaked out the artist of the day.  How does that work?  Red, orange, yellow, green, blue, violet gives you white.  The laws of optics.  He discovers the laws of motion and the universal law of gravitation.  Then, a friend of his says, “Well, why do these orbits of the planets… Why are they in a shape of an ellipse, sort of flattened circle?  Why aren’t… some other shape?”  He said, you know, “I can’t… I don’t know.  I’ll get back to you.”  So he goes… goes home, comes back couple of months later, “Here’s why.  They’re actually conic sections, sections of a cone that you cut.”  And… And he said, “Well, how did find this out?  How did you determine this?”  “Well, I had to invent integral and differential calculus to determine this.”  Then, he turned 26.  Then, he turned 26.  We got people slogging through calculus in college just to learn what it is that Isaac Newtown invented on a dare, practically.  So that’s my man, Isaac Newton. 


Let us examine the actual history of science content of this stream of consciousness bullshit. We get told, “He discovers the laws of optic…!” Now Isaac Newton is indeed a very important figure in the history of physical optics but he by no means discovered the laws of optics. By the time he started doing his work in optics he stood at the end of a two thousand year long chain of researchers, starting with Euclid in the fourth century BCE, all of whom had been uncovering the laws of optics. This chain includes Ptolemaeus, Hero of Alexandria, al-Kindi, Ibn al-Haytham, Ibn Sahl, Robert Grosseteste, Roger Bacon, John Pecham, Witelo, Kamal al-Din al-Farisi, Theodoric of Freiberg, Francesco Maurolico, Giovanni Battista Della Porta, Friedrich Risner, Johannes Kepler, Thomas Harriot, Marco Antonio de Dominis, Willebrord Snellius, René Descartes, Christiaan Huygens, Francesco Maria Grimaldi, Robert Hooke, James Gregory and quite a few lesser known figures, much of whose work Newton was well acquainted with. Here we have an example of a generalisation that is so wrong it borders on the moronic.

What comes next is on safer ground, “…figured out that white light is composed of colors…” Newton did in fact, in a series of groundbreaking experiment, do exactly that. However NdGT, like almost everybody else is apparently not aware that Newton was by no means the first to make this discovery. The Bohemian Jesuit scholar Jan Marek (or Marcus) Marci (1595–1667) actually made this discovery earlier than Newton but firstly his explanation of the phenomenon was confused and largely wrong and secondly almost nobody knew of his work so the laurels go, probably correctly, to Newton.

NdGT’s next statement is for a physicist quite simply mindboggling he says, “That freaked out the artist of the day.  How does that work?  Red, orange, yellow, green, blue, violet gives you white.” Apparently NdGT is not aware of the fact that the rules for mixing coloured light and those for mixing pigments are different. I got taught this in primary school; NdGT appears never to have learnt it.

Up next are Newton’s contributions to mechanics, “He discovers the laws of motion and the universal law of gravitation.  Then, a friend of his says, “Well, why do these orbits of the planets… Why are they in a shape of an ellipse, sort of flattened circle?  Why aren’t… some other shape?”  He said, you know, “I can’t… I don’t know.  I’ll get back to you.”  So he goes… goes home, comes back couple of months later, “Here’s why.  They’re actually conic sections, sections of a cone that you cut.””

Where to begin? First off Newton did not discover either the laws of motion or the law of gravity. He borrowed all of them from others; his crowing achievement lay not in discovering them but in the way that he combined them. The questioning friend was of course Edmond Halley in what is one of the most famous and well document episodes in the history of physics, so why can’t NdGT get it right? What Halley actually asked was, assuming an inverse squared law of attraction what would be the shape of aa planetary orbit? This goes back to a question posed earlier by Christopher Wren in a discussion with Halley and Robert Hooke, “would an inverse squared law of attraction lead to Kepler’s laws of planetary motion?” Halley could not solve the problem so took the opportunity to ask Newton, at that time an acquaintance rather than a friend, who supposedly answered Halley’s question spontaneously with, “an ellipse.” Halley then asked how he knew it and Newton supposedly answered, “I have calculated it.” Newton being unable to find his claimed calculation sent Halley away and after some time supplied him with the nine-page manuscript De motu corporum in gyrum, which in massively expanded form would become Newton’s Principia.

NdGT blithely ignoring the, as I’ve said, well documented historical facts now continues his #histsigh fairy story, “And he said, “Well, how did find this out?  How did you determine this?”  “Well, I had to invent integral and differential calculus to determine this.”” This is complete an utter bullshit! This is in no way what Newton did and as such he also never claimed to have done it. In fact one of the most perplexing facts in Newton’s biography is that although he was a co-discoverer/co-inventor of the calculus (we’ll ignore for the moment the fact that even this is not strictly true, read the story here) there is no evidence that he used calculus to write Principia.

NdGT now drops his biggest historical clangour! He says, “Then, he turned 26.  Then, he turned 26.  We got people slogging through calculus in college just to learn what it is that Isaac Newtown invented on a dare, practically.  So that’s my man, Isaac Newton.” Newton was twenty-six going on twenty seven when he carried out the optics research that led to his theory of colours in 1666-67 but the episode with Halley concerning the shape of planetary orbits took place in 1682 when he was forty years old and he first delivered up De motu corporum in gyrum two years later in 1684. NdGT might, as an astro-physicist, be an expert on a telescope but he shouldn’t telescope time when talking about historical events.


Filed under History of Optics, History of science, Myths of Science, Newton

Perpetuating the myths addendum – ‘The Copernican Shock

Frequent Renaissance Mathematicus commentator (comment-writer, commenter, commentor), Phillip Helbig, sent me an interesting email in response to my previous blog post. In skewering the Nadlers’ comic book I didn’t actually comment on every single detail of everything that was wrong with it, one of the things I left out was Galileo saying:

It is not the center of the cosmos it is a planet just like the others and they all orbit the sun.

As Phillip correctly pointed out in the Ptolemaic-Aristotelian geocentric model of the cosmos the Earth was not viewed as the centre of the cosmos but rather as the bottom. I wrote a brief post long ago quoting a wonderful passage by Otto von Guericke, the inventor of the vacuum pump on exactly this topic:

Since, however, almost everyone has been of the conviction that the earth is immobile since it is a heavy body, the dregs, as it were, of the universe and for this reason situated in the middle or the lowest region of the heaven

Otto von Guericke; The New (So-Called) Magdeburg Experiments of Otto von Guericke, trans. with pref. by Margaret Glover Foley Ames. Kluwer Academic Publishers, Dordrecht/Boston/London, 1994, pp. 15 – 16. (my emphasis)

Phillip then asks, “So what was the “shock” of the Copernican Revolution (how many even get that pun?)?  Was it demoting humanity from the centre of the universe, or promoting the Earth to be on par with the other heavenly bodies?”

Before I answer his question I would point out that the idea that Copernicus had demoted the Earth from the centre of the cosmos first emerged much later, sometime in the late eighteenth or early nineteenth century, as an explanation for the supposed irrational rejection of the heliocentric hypothesis. Of course as is now well known, or at least should be, the initial rejection of the heliocentric hypothesis was not irrational but was based on solid common sense and the available empirical scientific evidence nearly all of which spoke against it. For a lot, but by no means all, of the astronomical arguments read Chris Graney’s excellent Setting Aside All Authority.

So back to Phillip’s question, what was the real Copernican shock? The answer is as simple as it is surprising, there wasn’t one. The acknowledgement and acceptance of the heliocentric hypothesis was so gradual and spread out over such a long period of time that it caused almost no waves at all.

First up, there was nothing very new in Copernicus suggesting a heliocentric cosmos. As should be well known it had already been proposed by Aristarchus of Samos in the third century BCE and Ptolemaeus’ Syntaxis Mathematiké (Almagest) contains a long section detailing the counter arguments to it, which were well known to all renaissance and medieval astronomers. Also in the centuries prior to Copernicus various scholars such as Nicholas of Cusa had extensively discussed both geocentric models with diurnal rotation and full heliocentric ones. All that was new with Copernicus was an extensive mathematical model for a heliocentric cosmos.

At first this was greeted with some enthusiasm as a purely hypothetical model with the hope that it would deliver better predictions of the heavenly movements than the geocentric models for use in astrology, cartography, navigation etc. However it soon became apparent that Copernicus was not really any better than the older models, as it was based on the same inaccurate and oft corrupted data as Ptolemaeus, so the interest waned, although it was these inaccuracies in both model that inspired Tycho Brahe to undertake his very extensive programme of new astronomical observations on which Kepler would base his models.

As Robert Westman pointed out, in a now legendary footnote, between the publication of De revolutionibus in 1543 and 1600 there were only ten people in the whole world, who accepted Copernicus’ heliocentric cosmology, not exactly earth shattering. Even after 1600 the acceptance of a heliocentric worldview only increased very slowly and in gradual increments as the evidence for it accumulated.

The first two factors are the work of Kepler and the early telescopic discoveries. Because Kepler couldn’t or rather didn’t deal with the physical problems of a moving earth his work initially fell on deaf ears. The early telescopic discoveries only refuted a pure Ptolemaic geocentric model but were consistent with a Tychonic geo-heliocentric one and as this had a stationary earth, it became the model of choice. Of interest, and I think up till now not adequately explained, a Tychonic model with diurnal rotation, i.e. a spinning earth, became the preferred variation. A partial step in the right direction. Kepler’s publication of the Rudolphine Tables in 1627 led to an acceptance of his elliptical astronomy at least for calculations if not cosmologically. Then Cassini, with the help of Riccioli, demonstrated with a heliometer in the San Petronio Basilica in Bologna that the sun’s orbit around the earth or the earth’s orbit around the sun was indeed a Keplerian ellipse, but couldn’t determine which of the two possibilities was the right one. Another partial step in the right direction.

Both Kepler’s first and third laws, solidly empirical, were now accepted but his second law still caused problems. Around 1670 Nicholas Mercator provided a new solid proof of Kepler’s second law and it is about then that the majority of European astronomers finally accepted heliocentricity, although it was Kepler’s elliptical astronomy and not Copernicus’ model; the two models were regarded as competitors; also there was still a distinct lack of empirical proof for a heliocentric cosmos.

The developments in physics over the seventeenth century combined with the discovery of the physical reality of the atmosphere and Newton’s gravitation law finally solved the problems of why, if the earth is moving various disasters don’t occur: high winds, atmosphere blowing away etc., all of those arguments already listed by Ptolemaeus. The final empirical proofs of the annual orbit, Bradley and stellar aberration in 1727, and diurnal rotation, measuring the shape of the earth, around 1750, were delivered in the eighteenth century.

As can been seen by this very brief outline of the acceptance and confirmation of heliocentrism it was a process that took nearly two hundred years and proceeded in small increments so there was never anything that could possibly be described as a shock. As already stated above the concept that the ‘Copernican Revolution’ caused consternation or was a shock is a myth created sometime in the late eighteenth or early nineteenth century to explain something that never took place. One might even call it fake news!

Addendum: A lot of the themes touched on here are dealt with in greater detail in my The transition to heliocentricity: The Rough Guides series of blog posts


Filed under History of Astronomy, History of science, Myths of Science

Perpetuating the myths

Since the re-emergence of science in Europe in the High Middle Ages down to the present the relationship between science and religion has been a very complex and multifaceted one that cannot be reduced to a simple formula or a handful of clichés. Many of the practitioners, who produced that science, were themselves active servants of their respective churches and many of their colleagues, whilst not clerics, were devoted believers and deeply religious. On they other had there were those within the various church communities, who were deeply suspicious of or even openly hostile to the newly won scientific knowledge that they saw as a threat to their beliefs. Over the centuries positions changed constantly and oft radically and any historian, who wishes to investigate and understand that relationship at any particular time or in any given period needs to tread very carefully and above all not to approach their research with any preconceived conclusions or laden down with personal prejudices in one direction or another.

In the nineteenth century just such preconceived conclusions based on prejudice became dominant in the study of the history of science propagated by the publications of the English-American chemist John William Draper and his colleague the American historian and educator Andrew Dickson White. These two scholar propagated what is now know as the Conflict or Draper-White Thesis, which claims that throughout history the forces of science and religion have been in permanent conflict or even war with each other. Draper wrote in his provocatively titled, History of the Conflict between Religion and Science (1874)

The history of Science is not a mere record of isolated discoveries; it is a narrative of the conflict of two contending powers, the expansive force of the human intellect on one side, and the compression arising from traditionary faith and human interests on the other.

In 1876 in his equally provocative The Warfare of Science, White wrote:

In all modern history, interference with science in the supposed interest of religion, no matter how conscientious such interference may have been, has resulted in the direst evils both to religion and to science—and invariably. And, on the other hand, all untrammeled scientific investigation, no matter how dangerous to religion some of its stages may have seemed, for the time, to be, has invariably resulted in the highest good of religion and of science.

Twenty years later White ramped up the heat in his A History of the Warfare of Science with Theology in Christendom.

Draper’s and White’s polemics became widely accepted and Galileo, Darwin and other figures out of the history of science came to be regarded as martyrs of science, persecuted by the bigoted forces of religion.

Throughout the twentieth century historians of science have striven to undo the damage done by the Draper-White thesis and return the history of the relationship between science and religion to the complex and multifaceted reality with which I introduced this post. They were not helped in recent decades by the emergence of the so-called New Atheists and the ill considered and unfortunately often historically ignorant anti-religious polemics spewed out by the likes of Richard Dawkins and Sam Harris, supposedly in the name of freedom of thought. I have, although a life-long atheist myself, on more than one occasion taken up arms, on this blog, against the sweeping anti-religious generalisations with respect to the history of science spouted by the new atheist hordes.

So it was with more than slight sense of despair that I read the preview in The Atlantic of

A Graphic Novel About 17th-Century Philosophy with the title Heretics!

This is described by its publishers the Princeton University Press as follows:

An entertaining, enlightening, and humorous graphic narrative of the dangerous thinkers who laid the foundation of modern thought

The Atlantic’s review/preview confirmed my darkest suspicions. We get informed:

Dark spots across the sun, men burned at the stake, an all-powerful church that brooks no idea outside its dogma—there is no subject so imbued with drama, intrigue, and fast-paced action as 17th-century Western philosophy. And thus no medium does it justice like the graphic novel.

No, really.

Heretics!, a graphic novel by Steven and Ben Nadler, introduces readers to what is arguably the most interesting, important, and consequential period in the history of Western philosophy. While respecting recent scholarship on 17th-century thought, [my emphasis] the Nadlers sought to make these stories and ideas as accessible and engaging to as broad an audience as possible without condescension. At times, this called for some historical liberties and anachronism. (Full disclosure: there were no laptop computers or iPods in the 17th century.)

We are back in Draper-White territory with a vengeance! The last thing that the Nadlers do is to respect recent scholarship, in fact they turn the clock back a long way, deliberately avoiding all the work done by modern historians of science.

The sample chapter provided by The Atlantic starts with Giordano Bruno, who else, much loved as a martyr for science by the new atheist hordes.

Source: The Atlantic

We see here that, as usual, Bruno’s cosmology is featured large, whilst his theological views are tucked away in the corner. Just two comments, Bruno was by no stretch of the imagination a scientist, read this wonderful essay by Tim O’Neill if you don’t believe me, and his “highly unorthodox” theological views included denial of the trinity, denial of Jesus’ divinity and denial of the virgin birth any one of which would have got him a free roasting courtesy of the Catholic Church if he had never written a single word about cosmology.

Up next, prime witness for the prosecution, who else but our old friend Galileo Galilei. We get the hoary old cliché of him throwing rocks off the Leaning Tower of Pisa, which he almost certainly never did.

We now move on to Galileo the astronomer,

Source: The Atlantic

who having made his telescopic discoveries claims that, “Copernicus was right.”

Source: The Atlantic

Know what, in 1615 Galileo was very careful not to claim that because he knew that it was a claim that he couldn’t back up. What he did do, which brought him into conflict with the Church was to suggest that the Church should change its interpretations of the Bible, definitely not on for a mere mathematician in the middle of the Counter Reformation and for which he got, not unsurprisingly, rapped over the knuckles. In 1616 Pope Paul V did not condemn Copernicus’s theory as heresy, in fact no pope ever did.

We then have Galileo sulking in his room and he isgoing to show them! In fact Galileo courted the Catholic Church and was a favourite of the papal court in Rome; he received official permission from Pope Urban VIII to write his Diologo. I’m not going to go into the very complex detail as to why this backfired but a couple of short comments are necessary here. At that time the heliocentric theory did not do a much better job of explain the phenomena in the heavens and on earth. Galileo’s book is strong on polemic and weak on actual proofs. Also, and I get tired of pointing this out, Galileo was not condemned as a heretic but found guilty of grave suspicion of heresy. There is a massive legal difference between the two charges. Paying attention to the fine detail is what makes for a good historian. We close, of course with the classic cliché, “And yet the earth moves.” No, he didn’t say that!

Source: The Atlantic

We then get a comic book description of the differences between the philosophies of Aristotle and Descartes that unsurprisingly doesn’t do either of them justice. All of this is of course only a lead up to the fact that Descartes decided not to publish his early work explicating his philosophy including his belief in heliocentricity, Traité du monde et de la lumière, on hearing of Galileo’s trial and punishment. This is dealt with by the Nadlers with a piece of slapstick humour, “Zut alors! I don’t want to get into trouble too!” Has anybody ever actually heard a Frenchman say “Zut alors!”?

Source: The Atlantic

This episode in intellectual history is actually of great interest because as far as is known Descartes is the only author in the seventeenth century who withdrew a book from publication because of the Pope’s edict against teaching heliocentricity. He appears to have done so not out of fear for his own safety but out of respect for his Jesuit teachers, whom he did not wish to embarrass. This was rather strange as other Jesuits and students of Jesuit academies wrote and published books on heliocentrism merely prefacing them with the disclaimer that the Holy Mother Church in its wisdom has correctly condemned this theory but it’s still quite fun to play with it hypothetically. The Church rarely complained and appearances were maintained.

This very superficial and historically highly inaccurate comic book in no way does justice to its subject but will do a lot of damage to the efforts of historians of science to present an accurate and balanced picture of the complex historical relationship between science and religion.

For anybody who is interested in the real story I recommend John Hadley Brooke’s classic Science and Religion: Some Historical Perspectives (1991) and Peter Harrison’s, soon to be equally classic, The Territories of Science and Religion (2015). On reading The Atlantic review/preview Peter Harrison tweeted the following:

Oh dear…. Not the optimal format for communicating the complexities of history – Peter Harrison (@uqharri)

James Ungureanu another expert on the relations between science, religion and culture also tweeted his despair on reading The Atlantic review/preview:

When I saw this earlier, I died a little. It must be right because it’s funny! – James C Ungureanu (@JamesCUngureanu)


Filed under Book Reviews, History of science, Myths of Science

The problem with superlatives

I have on several occasions in the past written about the problems of the use of certain superlative terms in presentations of the history of science, in particular in popular ones, such as first, father of, founder of and the greatest, as they only lead to a distortion of what really happens in the historical evolution of the scientific disciplines.

The term the greatest reared its ugly head again last week in the form of a tweet by Professor Frank McDonough (@FXMC1957) (historian).

18 April 1955. Albert Einstein (aged 76) died. He was arguably the greatest scientist who ever lived.

If Einstein is arguably the greatest scientist who ever lived, it raises the question, who his competitors might possibly be for this obviously coveted accolade. A typical discussion would almost certainly immediately throw up the names Isaac Newton, Galileo Galilei and Archimedes, going backwards in time. This almost canonical list, including of course Einstein, throws up a whole series of problems.

For me personally the first problem is that the list almost never includes Johannes Kepler, although any serious and unbiased comparison of their achievements, and they were contemporaries, would show quite clearly that Kepler actually contributed significantly more to the evolution of the sciences than Galileo. However for various reasons Kepler lacks the historical nimbus that Galileo has acquired down the centuries.

The second problem is that one is not actually comparing like with like. The mathematician and maths historian Eric Temple bell, whose book Men of Mathematics ignited my interest in the history of mathematics as a teenager, asked the question, “who was the greatest mathematician of all times?” He came up with a list of three names Archimedes, Isaac Newton and Johann Carl Friedrich Gauss (Gauss was also an extraordinary polymath who made important and significant contributions to astronomy, geodesy, cartography, optics, mechanics and, and…, so why isn’t he ever on the greatest scientist lists?). Bell then argued that it was impossible to say, which of the three was the greatest in terms of their mathematical achievements but Archimedes was operating on a much smaller basis of pre-existing knowledge so his achievements should be judged as greater.

Bell’s argument has a certain historical validity and makes us very much aware of the problems and dangers of trying to compare the achievements of practitioners of science across the depths of time. Galileo’s achievements can only be judged against the background of the late sixteenth century and early seventeenth, Newton’s against the background of the late seventeenth, when the situation in physics and astronomy was very different to that at the beginning of the century. Both of them are separated by a vast gulf in time from Archimedes and although the gap between Newton and Einstein is smaller the difference in background situations is immense. In the end we can only really compare a given scientist with his contemporaries.

Another problem that the canonical list immediately calls to attention is that all four of our candidates are basically mathematical physicists, which displays a strong bias against all the other scientific disciplines. This bias has existed for a very long time and is one of the things that current historians of science try to combat. For a very long time the history of science was seen principally as the history of the exact sciences i.e. mathematics, astronomy and physics. All other disciplines tended to be treaded as somehow secondary. Also the philosophy of science tended to be defined as the philosophy of physics. Returning to our list and its built in bias, not a few life scientists on reading it would say, quite correctly, what about Charles Darwin? Is not the discovery of the principle of evolution equal or even superior to anything discovered by the physicists or the astronomers? Having opened that can of worms somebody might put in a vote for Watson and Crick, after all Matthew Cobb’s excellent book on the discovery of the structure of DNA is titled, Life’s Greatest Secret! Oh dear that nasty superlative has crept in again.

At this point the chemists, who always get left out of such discussions, could well chime in with claims for Joseph Priestley, Antoine Lavoisier, Humphry Davy, Justus von Liebig and of course Marie Curie (after all she got two Nobels whereas Albert only got one!). Having brought up Humphry Davy a self taught, brilliant scientist, one should immediately think of his famous assistant and successor, the equally self taught, Michael Faraday; now there is a serious candidate for the greatest.

Another problem with this form of historical deification of scientists, the greatest, is that it fosters and perpetuates the myth of the lone genius. Returning to Einstein, undoubtedly an incredibly productive physicist, who contributed substantially to two of the biggest fields in twentieth century physics, his work built on the work of many, many others and contributions were made to the development of his own major discoveries, Relativity and Quantum Theory, by a fairly large group of other mathematicians, physicists and astronomers. No scientist exists in a vacuum but is part of a collective endeavour pushing forward the boundaries of their discipline. Historians of science should not concern themselves with the irrelevant and uninformative question, who’s the greatest, but should rather try to embed individuals into the context in which they did their work and the nexus of others who contributed to that work and those effected by it in their own efforts. Context is everything could well be the motto of this blog.


Filed under History of science, Myths of Science