Category Archives: Myths of Science

Repeat after me! – They knew it was round, damn it!

Last week saw various reports about a rare stolen copy of a Columbus letter that had turned up in the Library of Congress and has now been restored to its Italian owners; a comparatively happy end to one of a series of recent stories about the theft of precious books and documents from archives and libraries. Unfortunately the report on the website of NPR (that’s National Public Radio a non-commercial public American educational radio network) opened with the following paragraph:

The heist of a major historical document apparently went undiscovered for more than 20 years. Now, a stolen letter from Christopher Columbus spreading the news that the world isn’t flat has been returned from the U.S. to Italy.

As some readers might already have guessed the second sentence, specifically the phrase spreading the news that the world isn’t flat, had me screaming and banging my head against the wall to relieve the pain. This is just horrendously wrong in several different ways.

Posthumous portrait of Christopher Columbus by Sebastiano del Piombo, 1519. There are no known authentic portraits of Columbus. Source: Wikimedia Commons

Posthumous portrait of Christopher Columbus by Sebastiano del Piombo, 1519. There are no known authentic portraits of Columbus.
Source: Wikimedia Commons

On his first voyage Columbus set sail from Spain in September 1492 and after approximately a month of sailing westward he landed on a set of previous unknown islands, unknown to the Europeans that is. This voyage proves or disproves absolutely nothing about the shape of the earth. To even contemplate a voyage proving the earth to be spherical and not flat we would have to fast forward thirty years to the return to Spain of the one ship and eighteen men from Ferdinand Magellan’s disastrous circumnavigation in 1522; just for the record Magellan was not one of the eighteen survivors, so to call him the first man to circumnavigate the world, as many people do, is simply false. Some flat-earthers could, and probably do/did, argue that Magellan’s fleet just sailed round in a circle on a flat disc and not around a spherical earth so even that is not a totally convincing proof (even if the objection is somewhat iffy).

Let us return to the good Cristoforo. One could argue that he set sail westward to reach the Spice Islands, instead of heading to the east, as was normal because he believed the earth to be a sphere and also believed that that sphere was small enough that the route west to the Spice Islands was shorter and thus quicker than the route east (A belief, as it turns out, that was based on faulty calculation, of which more later). Having reached what he erroneously believed to be the Spice Islands, leading to the equally erroneous name, the West Indies, he believed that he had proved the world to be spherical. There is however a fundamental flaw in this argument. Columbus did not sail westward because he believed the earth to be a sphere; he did so because he, like almost every other educated European, knew that it was a sphere, knowledge that had been part of the European cultural heritage for the best part of two thousand years.

This should in the meantime be well known, but for those, like the NPR reporter(s), who have been sitting at the back and not paying attention let us pass review over those two thousand years.

We have no direct records but latter authors tell us that the Pythagoreans in the sixth century BCE already accepted that the earth was spherical. Their reasons for doing so are unknown but it was possible in analogy to the celestial sphere of the so-called fixed stars. If you look up into the heavens on a clear dark night the sky appears to take the form of an inverted bowl or hemisphere. By the latest in the fourth century BCE, Aristotle, who would go on to have a massive influence on European intellectual history, knew that the earth was spherical and he offers up a series of empirical proofs for this claim. For example he wrote, “there are stars seen in Egypt and […] Cyprus which are not seen in the northerly regions.” Since this could only happen on a curved surface, he too believed Earth was a sphere “of no great size, for otherwise the effect of so slight a change of place would not be quickly apparent.” (De caelo, 298a2–10). He also pointed out that the shadow of the earth on the moon during a lunar eclipse is circular. Following Aristotle all Greek schools of philosophy accepted that the earth was spherical and following them the Romans. There was no doubt in the classical world that the earth was a sphere. Ptolemaeus, the most influential Greek astronomer, brought a series of arguments and proofs for the spherical form of the earth in his Syntaxis Mathematiké (Almagest) in the second century CE. Most notably that as ships approach over the horizon one sees the top of the mast before one sees the hull.

A lot of this specific knowledge got temporarily lost within Europe in the Early Middle Ages but still almost nobody who was educated doubted that the earth was a sphere. With the rise of the Islamic empire the astronomers writing in Arabic adopted the views of Aristotle and Ptolemaeus including the spherical form of the earth.

Back in the third century BCE the astronomer mathematician Eratosthenes from Alexandria determined the size of the sphere using the angle of the sun’s shadow and a bit of basic trigonometry. He achieved a fairly accurate result, its accuracy depends on which Stadia (an ancient measure of length) you think he used; we don’t know for certain. Other geographers and astronomers also determined the size of the earth’s sphere; all arriving at reasonable ball park figures. Ptolemaeus, in his Geōgraphikḕ (Geography) also determined that the known land area the oikoumenè, Europe, Africa and Asia, stretched over 180° of the earth’s surface from east to west.

In the High Middle Ages, Europe regained this knowledge, largely via the Islamic Empire through Spain and Sicily. The standard European university astronomy text Johannes de Sacrobosco’s De sphaera mundi, written in the twelfth century CE, contained all the standard Greek arguments for a spherical earth including the lunar eclipse shadow, ship breasting the horizon and the change in visible asterism travelling from south to north. There existed no doubt amongst the educated in the Middle Ages that the earth was a sphere.

Picture from a 1550 edition of De sphaera, showing the earth to be a sphere. Source: Wikimedia Commons

Picture from a 1550 edition of De sphaera, showing the earth to be a sphere.
Source: Wikimedia Commons

When Columbus started making his plans at the end of the fifteenth century he knew that the world was a sphere, as did all of the people he tried to get to back his scheme. The only disputed point was how big the earth’s sphere was, how long the central landmass, Europe, Africa and Asia, was and thus how far the Spice Islands were if one sailed west from Europe. It was here that Columbus made some fundamental calculating errors. The Arabic astronomer al-Farghānī gave 5623 Arabic miles (being 111.8 km) as the length of one degree of longitude, whereas Ptolemaeus gave 6023 Roman miles (being 89.7 km). Columbus took al-Farghānī’s figure but multiplied it with the length of a Italian mile (much shorter than the Arabic one) to determine the circumference of the earth thus arriving at a figure that was far too small: approx. 25,255 km instead of al-Farghānī’s very accurate figure of 40,248 km. Ptolemaeus’ estimate of the spread of the main landmass was 180°, whereas it is in fact only about 130°. Columbus however took the even more inaccurate estimate of Marius from Tyre of 225°. The sum of these error meant that Columbus thought he only had about 3,700 km from the Canary Islands to Japan instead of the real 19,600 km! Having convinced his sponsors of the correctness of his calculations he set sail. If America had not been in the way Columbus and his entire crew would have stared starved to death on the open ocean.

So where does the myth of the flat earth come from? There were a few European scholars in antiquity and the early Middle Ages who, against the evidence, still argued that the earth was flat. However none of them enjoyed much support. One of the ironies of history is that Copernicus probably drew attention to the most famous of them, the third century cleric Lucius Caecilius Firmianus Lactantius, by mentioning him in his De revolutionibus. The real myth of the medieval flat earth begins first in the eighteenth and nineteenth centuries and has two principal sources. Probably the most influential of these was the American author Washington Irving who in his fictional biography of Columbus claimed that Columbus had to fight against the Church’s belief that the world was flat in order to get permission and backing for his voyage, a complete fabrication. This falsehood was supported by the nineteenth centuries false interpretation of the medieval T and O Mappa Mundi.

The Hereford Mappa Mundi, about 1300, Hereford Cathedral, England. Source: Wikimedia Commons

The Hereford Mappa Mundi, about 1300, Hereford Cathedral, England.
Source: Wikimedia Commons

These medieval world maps were in the form of a circle, the O, with the three known continents, Europe, Africa and Asia, displayed in the form of a T with east at the top. These maps were interpreted in the nineteenth century as indicating that the medieval cartographers believed the earth to be a flat disc. This is not without irony as they were circular in order to indicate that the world in a sphere. The myth of the flat medieval world was taken up by two figures well known to readers of this blog John William Draper (1811–1882) and Andrew Dickson White (1832–1918) in their widespread myth of the eternal war between religion and science. Science believing in a spherical earth whereas the reactionary Church believed in a flat one.

That Europe in the Middle Ages believed in a flat earth is a total myth that just doesn’t seem to want to die. The next time somebody tells you that the medieval Church thought the world was flat, or that Columbus was a revolutionary for believing in a spherical earth or any other version of this nonsense, do me a favour, take a large, heavy, flat, round, metal object, such as a frying pan, and beat them around the head with it.




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

Isaac and the apple – the story and the myth

The tale of Isaac Newton and the apple is, along with Archimedes’ bath time Eureka-ejaculation and Galileo defiantly mumbling ‘but it moves’ whilst capitulating before the Inquisition, is one of the most widely spread and well known stories in the history of science. Visitors to his place of birth in Woolsthorpe get to see a tree from which the infamous apple is said to have fallen, inspiring the youthful Isaac to discover the law of gravity.

The Woolsthorpe Manor apple tree Source:Wikimedia Commons

The Woolsthorpe Manor apple tree
Source:Wikimedia Commons

Reputed descendants of the tree exist in various places, including Trinity College Cambridge, and apple pips from the Woolsthorpe tree was taken up to the International Space Station for an experiment by the ‘first’ British ISS crew member, Tim Peake. Peake’s overalls also feature a Principia patch displaying the apple in fall.

Tim Peake's Mission Logo

Tim Peake’s Mission Logo

All of this is well and good but it leads automatically to the question, is the tale of Isaac and the apple a real story or is it just a myth? The answer is that it is both.

Modern historians of Early Modern science tend to contemptuously dismiss the whole story as a myth. One who vehemently rejects it is Patricia Fara, who is an expert on Newtonian mythology and legend building having researched and written the excellent book, Newton: The Making of Genius[1]. In her Science: A Four Thousand Year History she has the following to say about the apple story[2]:

More than any other scientific myth, Newton’s falling apple promotes the romantic notion that great geniuses make momentous discoveries suddenly and in isolation […] According to simplistic accounts of its [Principia’s] impact, Newton founded modern physics by introducing gravity and simultaneously implementing two major transformations in methodology: unification and mathematization. By drawing a parallel between an apple and the Moon, he linked an everyday event on Earth with the motion of the planets through the heavens, thus eliminating the older, Aristotelian division between the terrestrial and celestial realms.


Although Newton was undoubtedly a brilliant man, eulogies of a lone genius fail to match events. Like all innovators, he depended on the earlier work of Kepler, Galileo, Descartes and countless others […]


The apple story was virtually unknown before Byron’s time. [Fara opens the chapter with a Byron poem hailing Newton’s discovery of gravity by watching the apple fall].

Whilst I would agree with almost everything that Fara says, here I think she is, to quote Kepler, guilty of throwing out the baby with the bath water. But before I explain why I think this let us pass review of the myth that she is, in my opinion, quite rightly rejecting.

The standard simplistic version of the apple story has Newton sitting under the Woolsthorpe Manor apple tree on a balmy summer’s day meditation on mechanics when he observes an apple falling. Usually in this version the apple actually hits him on the head and in an instantaneous flash of genius he discovers the law of gravity.

This is of course, as Fara correctly points out, a complete load of rubbish. We know from Newton’s notebooks and from the draughts of Principia that the path from his first studies of mechanics, both terrestrial and celestial, to the finished published version of his masterpiece was a very long and winding one, with many cul-de-sacs, false turnings and diversions. It involved a long and very steep learning curve and an awful lot of very long, very tedious and very difficult mathematical calculations. To modify a famous cliché the genius of Principia and the theories that it contains was one pro cent inspiration and ninety-nine pro cent perspiration.

If all of this is true why do I accuse Fara of throwing out the baby with the bath water? I do so because although the simplistic story of the apple is a complete myth there really was a story of an apple told by Newton himself and in the real versions, which differ substantially from the myth, there is a core of truth about one step along that long and winding path.

Having quoted Fara I will now turn to, perhaps Newton’s greatest biographer, Richard Westfall. In his Never at Rest, Westfall of course addresses the apple story:

What then is one to make of the story of the apple? It is too well attested to be thrown out of court. In Conduitt’s version one of four independent ones, …

Westfall tells us that the story is in fact from Newton and he told to on at least four different occasions to four different people. The one Westfall quotes is from John Conduitt, who was Newton’s successor at the Royal Mint, married his niece and house keeper Catherine Barton and together with her provided Newton with care in his last years. The other versions are from the physician and antiquarian William Stukeley, who like Newton was from Lincolnshire and became his friend in the last decade of Newton’s life, the Huguenot mathematician Abraham DeMoivre, a convinced Newtonian and Robert Greene who had the story from Martin Folkes, vice-president of the Royal Society whilst Newton was president. There is also an account from Newton’s successor as Lucasian professor, William Whiston, that may or may not be independent. The account published by Newton’s first published biographer, Henry Pemberton, is definitely dependent on the accounts of DeMoivre and Whiston. The most well known account is that of Voltaire, which he published in his Letters Concerning the English Nation, London 1733 (Lettres philosophiques sur les Anglais, Rouen, 1734), and which he says he heard from Catherine Conduitt née Barton. As you can see there are a substantial number of sources for the story although DeMoivre’s account, which is very similar to Conduitt’s doesn’t actually mention the apple, so as Westfall says to dismiss it out of hand is being somewhat cavalier, as a historian.

To be fair to Fara she does quote Stukeley’s version before the dismissal that I quoted above, so why does she still dismiss the story. She doesn’t, she dismisses the myth, which has little in common with the story as related by the witnesses listed above. Before repeating the Conduitt version as quoted by Westfall we need a bit of background.

In 1666 Isaac, still an undergraduate, had, together with all his fellow students, been sent down from Cambridge because of an outbreak of the plague. He spent the time living in his mother’s house, the manor house in Woolsthorpe, teaching himself the basics of the modern terrestrial mechanics from the works of Descartes, Huygens and the Salisbury English translation of Galileo’s Dialogo. Although he came nowhere near the edifice that was the Principia, he did make quite remarkable progress for a self-taught twenty-four year old. It was at this point in his life that the incident with the apple took place. We can now consider Conduitt’s account:

In the year 1666 he retired again from Cambridge … to his mother in Lincolnshire & whilst he was musing in a garden it came to his thought that the power of gravity (wch brought an apple from the tree to the ground) was not limited to a certain distance from the earth but that this power must extend much further than was normally thought. Why not as high as the moon said he to himself & if so that must influence her motion & and perhaps retain her in her orbit, where-upon he fell to calculating what would be the effect of this supposition but being absent from books & taking common estimate in use among Geographers & our seamen before Norwood had measured the earth, that 60 English miles were contained in one degree latitude on the surface of the Earth his computation did not agree with his theory & inclined him to entertain a notion that together with the force of gravity there might be a mixture of that force wch the moon would have if it was carried along in a vortex…[3]

As you can see the account presented here by Conduitt differs quite substantially from the myth. No tree, no apple on the head, no instantaneous discovery of the theory of gravity. What we have here is a young man who had been intensely studying the theory of forces, in particular forces acting on a body moving in a circle, applying what he had learnt to an everyday situation the falling apple and asking himself if those forces would also be applicable to the moon. What is of note here is the fact that his supposition didn’t work out. Based on the data he was using, which was inaccurate, his calculations showed that the forces acting on the apple and those acting on the moon where not the same! An interesting thought but it didn’t work out. Oh well, back to the drawing board. Also of note here is the reference to a vortex, revealing Newton to be a convinced Cartesian. By the time he finally wrote the Principia twenty years later he had turned against Descartes and in fact Book II of Principia is devoted to demolishing Descartes’ vortex theory.

In 1666 Newton dropped his study of mechanics for the meantime and moved onto optics, where his endeavours would prove more fruitful, leading to his discoveries on the nature of light and eventually to his first publication in 1672, as well as the construction of his reflecting telescope.

The Newtonian Reflector Source: Wikimedia Commons

The Newtonian Reflector
Source: Wikimedia Commons

Over the next two decades Newton developed and extended his knowledge of mechanics, whilst also developing his mathematical skills so that when Halley came calling in 1684 to ask what form a planetary orbit would take under an inverse squared law of gravity, Newton was now in a position to give the correct answer. At Halley’s instigation Newton now turned that knowledge into a book, his Principia, which only took him the best part of three years to write! As can be seen even with this briefest of outlines there was definitely nothing instantaneous or miraculous about the creation of Newton’ masterpiece.

So have we said all that needs to be said about Newton and his apple, both the story and the myth? Well no. There still remains another objection that has been raised by historians, who would definitely like to chuck the baby out with the bath water. Although there are, as noted above, multiple sources for the apple-story all of them date from the last decade of Newton’s life, fifty years after the event. There is a strong suspicion that Newton, who was know to be intensely jealous of his priorities in all of his inventions and discoveries, made up the apple story to establish beyond all doubt that he and he alone deserved the credit for the discovery of universal gravitation. This suspicion cannot be simply dismissed as Newton has form in such falsification of his own history. As I have blogged on an earlier occasion, he definitely lied about having created Principia using the, from himself newly invented, calculus translating it back into conventional Euclidian geometry for publication. We will probably never know the final truth about the apple-story but I for one find it totally plausible and am prepared to give Isaac the benefit of the doubt and to say he really did take a step along the road to his theory of universal gravitation one summer afternoon in Woolsthorpe in the Year of Our Lord 1666.

[1] Patricia Fara, Newton: The Making of Genius, Columbia University Press, 2002

[2] Patricia Fara, Science: A Four Thousand Year History, ppb. OUP, 2010, pp. 164-165

[3] Richard S. Westfall, Never at Rest: A Biography of Isaac Newton, ppb. CUP, 1980 p. 154


Filed under History of Astronomy, History of Mathematics, History of Optics, History of Physics, History of science, Myths of Science, Newton

Well no, actually he didn’t.

Ethan Siegel has written a reply to my AEON Galileo opinion piece on his Forbes blog. Ethan makes his opinion very clear in the title of his post, Galileo Didn’t Invent Astronomy, But He DID Invent Mechanical Physics! My response is also contained in my title above and no, Galileo did not invent mechanical physics. For a change we’ll start with something positive about Galileo, his inclined plane experiments to determine the laws of fall, the description of which form the bulk of Ethan’s post, are in fact one of the truly great pieces of experimental physics and are what makes Galileo justifiably famous. However the rest of Ethan’s post leaves much to be desired.

Ethan starts off by describing the legendary Leaning Tower of Pisa experiment, in which Galileo supposedly dropped two ball of unequal weight of the tower and measured how long they took to fall. The major problem with this is that Galileo almost certainly never did carry out this experiment, however both John Philoponus in the sixth century CE and Simon Stevin in 1586 did so, well before Galileo considered the subject. The laws of fall were also investigated theoretically by the so-called Oxford Calculatores, who developed the mean speed theory, the foundation of the laws of fall, and the Paris Physicists, who represented the results graphically, both in the fourteenth century CE. Galileo knew of the work of John Philoponus, the Oxford Calculatores and the Paris Physicists, even using the same graph to represent the laws of fall in his Two New Sciences, as Oresme had used four hundred years earlier. In the sixteenth centuries the Italian mathematician Tartaglia investigated the path of projectiles, publishing the results in his Nova Scientia, his work was partially validated, partially refuted by Galileo. His landsman Benedetti anticipated most of Galileo’s results on the laws of fall. With the exception of Stevin’s work Galileo knew of all this work and built his own researches on it thus rather challenging Ethan’s claim that Galileo invented mechanical physics.

Galileo’s central achievement was to provide empirical proof of the laws of fall with his ingenious ramp experiments but even here there are problems. Galileo’s results are simply too good, not displaying the expected experimental deviations, leading Alexander Koyré, the first great historian of Galileo’s work, to conclude that Galileo never did the experiments at all. The modern consensus is that he did indeed do the experiments but probably massaged his results, a common practice. The second problem is that any set of empirical results requires confirmation by other independent researchers. Mersenne, a great supporter and propagator of Galileo’s physics, complains of the difficulties of reproducing Galileo’s experimental results and it was first Riccioli, who finally succeeded in doing so, publishing the results in 1651.

A small complaint is Ethan’s claim that Galileo’s work on the laws of fall “was the culmination of a lifetime of work”. In fact although Galileo first published his Two New Sciences in 1638 his work on mechanics was carried out early in his life and completed well before he made his telescopic discoveries.

The real problem with Ethan’s post is what follows the quote above, he writes:

…and the equations of motion derived from Newton’s laws are essentially a reformulation of the results of Galileo. Newton indeed stood on the shoulders of giants when he developed the laws of gravitation and mechanics, but the biggest titan of all in the field before him was Galileo, completely independent of what he contributed to astronomy.

This is quite simply wrong. After stating his first two laws of motion in the Principia Newton writes:

The principles I have set forth are accepted by mathematicians and confirmed by experiments of many kinds. By means of the first two laws and the first two corollaries Galileo found that the decent of heavy bodies is the squared ratio of the time that the motion of projectiles occurs in a parabola, as experiment confirms, except insofar as these motion are somewhat retarded by the resistance of the air.

As Bernard Cohen points out, in the introduction to his translation of the Principia from which I have taken the quote, this is wrong because, Galileo certainly did not know Newton’s first law. As to the second law, Galileo would not have known the part about change in momentum in the Newtonian sense, since this concept depends on the concept of mass which was invented by Newton and first made public in the Principia.

I hear Galileo’s fans protesting that Newton’s first law is the law of inertia, which was discovered by Galileo, so he did know it. However Galileo’s version of the law of inertia is flawed, as he believes natural unforced motion to be circular and not linear. In fact Newton takes his first law from Descartes who in turn took it from Isaac Beeckman. Newton’s Principia, or at least his investigation leading up to it, are in fact heavily indebted to the work of Descartes rather than that of Galileo and Descartes in turn owes his greatest debts in physics to the works of Beeckman and Stevin and not Galileo.

An interesting consequence of Newton’s false attribution to Galileo in the quote above is that it shows that Newton had almost certainly never read Galileo’s masterpiece and only knew of it through hearsay. Galileo’s laws of fall are only minimally present in the Principia and then only mentioned in passing as asides, whereas the parabola law occurs quite frequently whenever Newton is resolving forces in orbits but then only as Galileo has shown.

One small irony remains in Ethan’s post. He loves to plaster his efforts with lots of pictures and diagrams and videos. This post does the same and includes a standard physics textbook diagram showing the force vectors of a heavy body sliding down an inclined plane. You can search Galileo’s work in vain for a similar diagram but you will find an almost identical one in the work of Simon Stevin, who worked on physical mechanics independently of and earlier than Galileo. Galileo made some very important contributions to the development of mechanical physics but he certainly didn’t invent the discipline.


Filed under History of Mathematics, History of Physics, Myths of Science, Newton

A bit on the side

Galileo by Justus Sustermans/Wikipedia

Galileo by Justus Sustermans/Wikipedia

For those of my readers who don’t follow me on Twitter or Facebook I have indulged in my favourite pastime, slagging of Galileo Galilei, but this time in an opinion piece in the online science journal AEON. If you’ve already read my old Galileo post Extracting the stopper, this is just a shorter punchier version of the same. If not or if you want to read the updated sexy version then mosey on over to AEON and read Galileo’s reputation is more hyperbole than truth.


Filed under History of science, Myths of Science

It’s the wrong telescope.

I know I announced a blogging hiatus yesterday, but I have some time evenings and I simply couldn’t ignore this.

Caroline Herschel Source: Wikimedia Commons

Caroline Herschel
Source: Wikimedia Commons


Today is Caroline Herschel’s birthday and Google have celebrated it with a doodle, which is cool and an overdue acknowledgement of a great lady astronomer. If you don’t already know who Caroline Herschel is then you should read the two Guardian articles by Stuart Clark and Becky Higgitt. Google’s doodle is all well and good but I have a complaint, it’s the wrong telescope.

The Google doodle for Caroline Herschel’s 266th birthday. Photograph: google

The Google doodle for Caroline Herschel’s 266th birthday. Photograph: google

If you look at the picture Caroline is standing behind a mounted telescope and in the animated version of the doodle she bends down to look through the telescope as a comet flies passed overhead. This is to acknowledge the fact that she is most well known for the eight comets that she discovered. So what’s my problem? The telescope displayed in the doodle is a refractor that is a telescope with lenses at the front, the objective, and at the back, the eyepiece or ocular. The problem is that the Herschels, that is Caroline and her brother William, used reflectors; that is telescopes that have a mirror and not a lens as objective and then a lens or lenses as the eyepiece to observe the image created by the mirror. To be precise they used Newtonian reflectors that they built themselves. That they used Newtonians was rather unusual at the time because most other professional, or serious amateur like the Herschels, astronomers used Gregorian reflector telescopes, which are of a different design. The Gregorian is actually superior but the Newton is simpler to construct and this is almost certainly the reason that William stuck with Newtonians.

Replica of a Herschel Newtonian Refractor. Herschel Museum Bath Source: Wikimedia Commons

Replica of a Herschel Newtonian Reflector. Herschel Museum Bath
Source: Wikimedia Commons

Added: 17 March 2016

If you go to the article Caroline Lucretia Herschel – comet huntress (h/t Tony Angel)on the second page you can see sketches of the comet-sweeper Newtonian reflectors that William built for Caroline, which are not quite as elegant or impressive as the telescope pictured above but which served their purpose admirably.

The fact that the doodle shows a refractor and not a reflector is, viewed historically, not a trivial matter. In the eighteenth century the reflectors were capable of resolving much weaker light sources than the contemporary refractors and were thus superior for the type of deep space celestial mapping that William Herschel pioneered and which he taught to his younger sister. To show Caroline using a refractor and not a Herschel Newtonian reflector is a complete historical misrepresentation and totally misleading.

Now Google might argue that your average Google doodle viewer would probably not recognise a Herschel Newtonian reflector as a telescope and therefore they put a simple refractor in the picture as a generic telescope that people would recognise as such. All well and good but I can best explain my aversion by a simple analogy.

Lewis Hamilton is the current world Formula One racing champion. I want you to imagine the following. Next season Hamilton wins his fourth world championship and Google celebrate the occasion with one of their doodles, unlikely but you never know. So we get a cartoon of the well know figure of Lewis Hamilton in a Formula One racing car but he is not driving a Mercedes, the team for which he drives and has won two of his three titles up till now, but a Ferrari because that is the generic racing car that most people see in their minds eye when they think of racing cars. The Lewis Hamilton fans would probably launch a crusade against the Google head quarters in Mountain View and hang the offending doodler from a lamppost.

As far as I’m concerned in the history of science details matter a lot and the fact that the Herschels used Newtonian reflectors is not a triviality but an important factor in the astronomical achievements for which they are justifiably renowned. It should also be pointed out that this renown led to William becoming one of the commercially most successful telescope constructors in the eighteenth century because other astronomers wanted to own one of those telescopes, which had made the discoveries of William and Caroline possible.


Filed under History of Astronomy, Myths of Science

We’re British not European – Really?

Yesterday evening my #histsci soul sister Becky Higgitt tweeted the following:

Scientists for Britain on #bbcnews – we had Newton therefore we don’t want to be in Europe

As #histsci bloggers both Becky and I have been here before, Becky here on her H-Word blog at the Guardian and myself here on the Renaissance Mathematicus but as it’s something that can’t be said too often, I thought I would point out once again that science is collaborative and international and all attempts to claim it for some sort of lone genius, as is often the case with Newton, or to make nationalist claims on its behalf are a massive distortion of the history of science.

Becky’s tweet specifically mentions Britain’s science icon ‘numero uno’ Isaac Newton, so let’s take a look at his scientific achievements and the foundations on which they were built. As Newton, paraphrasing Bernard of Chartres, famously wrote in a letter to Robert Hooke: If I have seen further, it is by standing on the shoulders of giants. So who were these giants on whose shoulders Newton was perched? What follows is a bit shopping list I’m afraid and is by no means exhaustive, listing only the better known names of the predecessors in each area of study where Newton made a contribution.

Newton’s mathematics built on the work in algebra of Cardano and Bombelli, both Italians, and Stifel, a German, from the sixteenth century. Their work was built on the efforts of quite a large number of Islamic mathematicians who in turn owed a debt to the Indians and Babylonians. Moving on into the seventeenth century we have Viète, Fermat, Pascal and Descartes, all of them Frenchmen, as well as Oughtred, Wallis and Barrow representing the English and James Gregory the Scots. Italy is represented by Cavalieri. The Dutch are represented by Huygens and Van Schooten, whose expanded Latin edition of Descartes Géométrie was Newton’s chief source on the continental mathematics.

We see a similar pattern in Newton’s optics where the earliest influence is the 10/11th century Islamic scholar Ibn al-Haytham, although largely filtered through the work of others. In the seventeenth century we have Kepler and Schiener, both Germans, Descartes, the Frenchman, and Huygens, the Dutchman, pop up again along with Grimaldi, an Italian, Gassendi, another Frenchman, and James Gregory a Scot and last but by no means least Robert Hooke.

In astronomy we kick off in the fifteenth century with Peuerbach and Regiomontanus, an Austrian and a German, followed in the sixteenth century by Copernicus, another German. All three of course owed a large debt to numerous earlier Islamic astronomers. Building on Copernicus we have Tycho, a Dane, Kepler, a German, and of course Galileo, a Tuscan. France is once again represented by Descartes along with Ismael Boulliau. Also very significant are Cassini, an Italian turned Frenchman, and once again the ubiquitous Huygens. At last we can throw in a gaggle of Englishmen with Horrocks, Wren, Flamsteed, Halley and Hooke.

In physics we have the usual suspects with Kepler and Galileo to which we can add the two Dutchmen Stevin and Beeckman. Descartes and Pascal are back for the French and Borelli joins Galileo in representing Italy. Huygens once again plays a central role and one should not forget Hooke’s contributions on gravity.

As I said at the beginning these lists are by no means exhaustive but I think that they demonstrate very clearly that Newton’s achievements were very much a pan-European affair and thus cannot in anyway be used as an argument for an English or British science existing without massive European cooperation.

If we look at Newton’s scientific inheritance then things look rather bad for the British in the eighteenth century with the developments being made by a whole battalion of French, Swiss, German, Dutch and Italian researchers with not a Brit in sight anywhere. Things improved somewhat in the nineteenth century but even here the progress is truly international. If we take just one small example the dethroning of Newton’s corpuscular theory of light by the wave theory. Originated by Huygens and Hooke in the seventeenth century it was championed by Ampère, Fresnel, Poisson and Arago all of whom were French and by Young and Airy for the British in the nineteenth century.

I hope that yet again, with this brief example, I have made clear that science is a collaborative and cooperative enterprise that doesn’t acknowledge or respect national boundaries but wanders through the cultures where and when it pleases, changing nationalities and languages at will. Science is a universal human activity to which many different and varied cultures have made contributions and will continue to do so in the future. Science should have absolutely nothing to do with nationalism and chauvinism and politicians who try and harness it to their nationalist causes by corrupting its history are despicable.



Filed under History of science, Myths of Science, Newton

Founders of science?

World-renowned wheelchair driver and astrophysicist, Stephen Hawking, recently held the first of this year’s BBC Reith Lectures. This prompted the following tweet from Roger Highfield, science writer and director of external affairs at the Science Museum Group:

If Hawking could time travel, he would like to meet Galileo – ‘founder of modern science’ and ‘a bit of a rebel’ #Reith

Philip Ball, science writer, responded:

Though certainly not, as Hawking claimed, “the first to challenge Aristotle”…

To which I added:

Also not the founder of modern science.

Tom Levenson, another science writer, contributed:

Probably kicked his dog and stiffed his waiter too.

Roger Highfield reacted to this exchange thus:


This moderately amusing, or not depending on you point of view, exchange on Twitter prompted Ángel Lamuño, Philosophy & Theology Follower of Bernard J. F. Lonergan SJ (self description), to pose the following question to me:

Who is (are) the founder(s) of modern science?

This whole rather trivial exchange contains several worrying aspects for historians of science, starting with Hawking’s original utterance. This is by no means the first time that Hawking has made such statements in public and in fact I quote one such in my take down of the founder of modern science and similar claims about Galileo – Extracting the stopper – that I wrote more than five years ago and which I’m not going to repeat here. The real problem is here that whatever Hawking’s merits as an astro-physicist he is not a historian of science and this is reflected in the naivety of his history of science comments that are almost invariably false. The problem is that Hawking because of his physical disability has become the most famous scientist in the world instantly recognised and admired whenever he appears in public. Whenever he makes a comment about the history of science then the majority of his audience, who don’t know better, immediately believe him because it’s ‘Stephen Hawking’! People believe Hawking because of who he is and not because his facts are correct, they aren’t. The irony of this situation is that what we have here is knowledge by authority, exactly the non-scientific epistemology that the scholastics supposedly practiced and which Galileo is said to have swept away, making him in Hawking’s words ‘the founder of modern science’.

Equally worrying is Ángel Lamuño’s question, [if Galileo isn’t the founder of modern science] “who is (are) the founder(s) of modern science?” This question is, in my opinion, based on a widespread misconception as to how science has evolved (developed, if you don’t like the word evolved). The misconception is supported in a vast number of texts, many of them written by highly respected historians of science but I think, in the meantime, rejected by a substantial part of the history of science community.

This misconception, or rather set of misconceptions, is that somehow major changes in the history of science are caused by one driving force in mainstream scientific thought and/or brought about by one heroic individual.

The traditional story that I grew up with was that the scientific revolution came about because science became quantified or mathematized when Neo-Platonism replaced Aristotelian scholasticism as the dominant philosophy in Europe. This is, however, not the Neo-Platonism of Plotinus of the third century CE but a Pythagorean Neo-Platonism. This theory was mainly propagated by philosophers. Mathematic historians however challenged this theory accepting that the scientific revolution was a mathematization of science but that this was brought about by an Archimedean renaissance beginning in the fourteenth century. Others have noted that the period also saw both a Euclidean and a Ptolemaic renaissance leading to increases in mathematical activity.

A different popular version of the story is that the scientific revolution was driven by the astronomical revolution brought about singlehandedly by Copernicus publishing his De revolutionibus in 1543. This is somewhat undermined by two facts. Firstly Copernicus’ work is only part of a general reform of astronomy carried out by a fairly large number of astronomers beginning with the first Viennese School of Mathematics in the fifteenth century. Secondly the so-called scientific revolution consists of far more than just astronomy.

There are theories that the astronomical revolution was driven by the renaissance in mathematical cartography sparked by the rediscovery of Ptolemaeus’ Geographia in 1406, alternatively by an attempt to put astrology on a solid empirical footing. At least one Arabic author has argued, with more than a little justification, that the astronomical revolution owes much more to the preceding Islamic astronomy than is usual credited. Another group of historians see the roots of the astronomical revolution in a shift in basic philosophy but not in a Neo-Platonic renaissance but in a Stoic one in the fifteenth and sixteenth centuries.

Another theory sees the scientific revolution being the rise in empirical experimental science, which has its roots in alchemy. An alternative explanation for this rise lies in the development of modern gunpowder based warfare and empirical studies of gunnery. Some see the rise of modern warfare as the driving force behind mathematical cartography, itself the driving force behind astronomical reform.

The above are some, but by no means all, of the theories that have been put forward to explain the emergence of modern science in the early modern period. So which one is the correct one? The answer is, all of them! The emergence of modern science was not caused by one single thing but by a whole range of activities, discoveries, renaissances as well as economic and socio-political developments. As historians we have a strong tendency to oversimplify, to want to find the ‘one’ cause for a given historical development, whereas in fact that development is almost inevitably the result of the interaction of a complex web of causes and it is often very difficult to weight the respective contributions of the individual causes. The mono-causal explanation only occurs if the researcher views the development from one standpoint whilst actively or passively ignoring all other possible standpoints. The same is true of the attribution of the titles ‘father of’ or ‘founder of’ to individuals. If you follow the link above to my earlier post about Galileo you will see how I show that he was only one of several, and sometimes many, making positive contributions to the fields in which he was active in the early seventeenth century and to raise him up on a pedestal is to deny due credit to the others and thus to falsify history. One can do the same with any of the other so-called ‘heroes’ of science, as I did fairly recently with exaggerated claims, contained in a book’s subtitle, for Johannes Kepler.

To repeat my central mantra as a historian of science, the evolution of science is driven by multiple complexly intertwined causes and is realised by the collective efforts of, often large, groups of researches and not by exceptional individuals. One day I hope that people will stop making the sort of statements that Stephen Hawking made, and which sparked off this post, but if I’m honest I’m not holding my breath whilst I wait.



Filed under Myths of Science