Category Archives: History of science

Preach truth – serve up myths.

Over Christmas I poked a bit of fun at Neil deGrasse Tyson for tweeting that Newton would transform the world by the age of 30, pointing out he was going on forty-five when he published his world transforming work the Principia. The following day NdGT posted a short piece on Face Book praising his own tweet and its success. Here he justified his by the age of thirty claim but in doing so rode himself deeper into the mire of sloppy #histsci. You might ask why this matters, to which the answer is very simple. NdGT is immensely popular especially amongst those with little idea of science and less of the history of science and who hang on his every utterance. Numerous historians of science labour very hard to dismantle the myths of science and to replace them with a reasonable picture of how science evolved throughout its long and convoluted history. NdGT disdains those efforts and perpetuates the myths leading his hordes of admirers up the garden path of delusion. Let us take a brief look at his latest propagation of #histmyth.

NdGT’s post starts off with the news that his Newton birthday tweet is the most RTed tweet he has every posted citing numbers that lesser mortals would not even dare to dream about. This of course just emphasises the danger of NdGT as disseminator of false history of science, his reach is wide and his influence is strong. Apparently some Christians had objected to NdGT celebrating Newton’s birthday on Christ’s birthday and NdGT denies that his tweet was intended to be anti-Christian but then goes on to quote the tweet that he sent out in answer to those accusations:

“Imagine a world in which we are all enlightened by objective truths rather than offended by them.”

Now on the whole I agree with the sentiment expressed in this tweet, although I do have vague vision of Orwellian dystopia when people from the scientism/gnu atheist camp start preaching about ‘objective truth’. Doesn’t Pravda mean truth? However I digress.

I find it increasing strange that NdGT’s craving for objective truth doesn’t stretch to the history of science where he seems to much prefer juicy myths to any form of objectivity. And so also in this case. In his post he expands on the tweet I had previously poked fun at. He writes:

Everybody knows that Christians celebrate the birth of Jesus on December 25th.  I think fewer people know that Isaac Newton shares the same birthday.  Christmas day in England – 1642.  And perhaps even fewer people know that before he turned 30, Newton had discovered the laws of motion, the universal law of gravitation, and invented integral and differential calculus.  All of which served as the mechanistic foundation for the industrial revolution of the 18th and 19th centuries that would forever transform the world.

What we are being served up here is a slightly milder version of the ‘annus mirabilis’ myth. This very widespread myth claims that Newton did all of the things NdGT lists above in one miraculous year, 1666, whilst abiding his time at home in Woolsthorpe, because the University of Cambridge had been closed down due to an outbreak of the plague. NdGT allows Newton a little more time, he turned 30 in 1672, but the principle is the same, look oh yee of little brain and tremble in awe at the mighty immaculate God of science Sir Isaac Newton! What NdGT the purported lover of objective truth chooses to ignore, or perhaps he really is ignorant of the facts, is that a generation of some of the best historians of science who have ever lived, Richard S. Westfall, D. T. Whiteside, Frank Manuel, I. Bernard Cohen, Betty Jo Teeter Dobbs and others, have very carefully researched and studied the vast convolute of Newton’s papers and have clearly shown that the whole story is a myth. To be a little bit fair to NdGT the myth was first put in the world by Newton himself in order to shoot down all his opponents in the numerous plagiarism disputes that he conducted. If he had done it all that early then he definitely had priority and the others were all dastardly scoundrels out to steal his glory. We now know that this was all a fabrication on Newton’s part.

Newton was awarded his BA in 1665 and in the following years he was no different to any highly gifted postgraduate trying to find his feet in the world of academic research. He spread his interests wide reading and absorbing as much of the modern science of the time as he could and making copious notes on what he read as well as setting up ambitious research programmes on a wide range of topics that were to occupy his time for the next thirty years. In the eighteen months before being sent down from Cambridge because of the plague he concentrated his efforts on the new analytical mathematics that had developed over the previous century. Whilst reading widely and bringing himself up to date on material that was not taught at Cambridge he simultaneously extended and developed what he was reading laying the foundations for his version of the calculus. It was no means a completed edifice as NdGT, and unfortunately many others, would have us believe but it was still a very notable mathematical achievement. Over the decades he would return from time to time to his mathematical researches building on and extending that initial foundation. He also didn’t ‘invent’ integral and differential calculus but brought together, codified and extended the work of many others, in particular, Descartes, Fermat, Pascal, Barrow and Wallace, who in turn looked back upon two thousand years of history on the topic.

In the period beginning in 1666 he left off with mathematical endeavours and turned his attention to mechanics mostly addressing the work of Descartes. He made some progress and even wondered, maybe inspired by observing a falling apple in his garden in Woolsthorpe, if the force which causes things to fall the Earth is the same as the force which prevents the Moon from shooting off at a tangent to its orbit. He did some back of an envelope calculations, which showed that they weren’t, due to faulty data and he dropped the matter. He didn’t discover the laws of motion and as he derived the law of gravity from Huygens’ law of centripetal force that was first published in 1673 he certainly didn’t do it before he was thirty. In fact most of the work that went into Newton’s magnum opus the Principia was done in an amazing burst of concentrated effort in the years between 1684 and 1687 when Newton was already over forty.

What Newton did do between 1666 and 1672 was to conduct an extensive experimental programme into physical optics, in particular what he termed the phenomenon of colour. This programme resulted in the construction of the first reflecting telescope and in 1672 Newton’s legendary first paper A Letter of Mr. Isaac Newton, Professor of the Mathematicks in the University of Cambridge; Containing His New Theory about Light and Colors published in the Philosophical Transactions of the Royal Society. Apparently optics doesn’t interest NdGT. Around 1666 Newton also embarked on perhaps his most intensive and longest research programme to discover the secrets of alchemy, whilst starting his life long obsession with the Bible and religion. The last two don’t exactly fit NdGT’s vision of enlightened objective truth.

Newton is without doubt an exceptional figure in the history of science, who has few equals, but like anybody else Newton’s achievements were based on long years of extensive and intensive work and study and are not the result of some sort of scientific miracle in his young years. Telling the truth about Newton’s life and work rather than propagating the myths, as NdGT does, gives students who are potential scientists a much better impression of what it means to be a scientist and is thus in my opinion to be preferred.

As a brief addendum NdGT points out that Newton’s birthday is not actually 25 December (neither is Christ’s by the way) because he was born before the calendar reform was introduced into Britain so we should, if we are logical, be celebrating his birthday on 4 January. NdGT includes the following remark in his explanation, “But the Gregorian Calendar (an awesomely accurate reckoning of Earth’s annual time), introduced in 1584 by Pope Gregory, was not yet adopted in Great Britain.” There is a certain irony in his praise, “an awesomely accurate reckoning of Earth’s annual time”, as this calendar was developed and introduced for purely religious reasons, again not exactly enlightened or objective.





Filed under History of Astronomy, History of Mathematics, History of Physics, History of science, Myths of Science, Renaissance Science

Just saying…

Neil deGrasse Tyson seems to have a real talent for very sloppy history of science. He pontificates on history of science topics without taking the trouble to check his facts. On Christmas day to acknowledge the birthday of Isaac Newton he tweeted the following:

On this day long ago, a child was born who, by age 30, would transform the world. Happy Birthday Isaac Newton b. Dec 25, 1642

Now, you would think that an astrophysicist would be able to cope with simple arithmetic but it seems to be beyond NdGT’s mental grasp. Newton, as he points out, was born in 1642. The contribution to science that he made that “would transform the world” can only refer to his Philosophiæ Naturalis Principia Mathematica and, as any historian of science could have told NdGT, this was published in 1687. Applying the subtraction algorithm, which most of us learnt in primary school, 1687 – 1642 = 45 and not thirty. Even being generous, as this is a fifty per cent error in the stated age at which Newton “would transform the world” we cannot really award NdGT anything but an F for this incredibly sloppy piece of work. Do try to do better next time Neil!


Filed under History of Astronomy, History of science, Newton

Someone is Wrong on the Internet.

Many of the readers of this blog will probably recognise the title of this post, as the punch line to one of the best ever xkcd cartoons. Regular readers will also know that the Renaissance Mathematicus cannot resist stamping on people who post inanely inaccurate or downright wrong history of science claims, comments etc. on the Internet. This last pre-Christmas post brings two examples of such foolishness that crossed our path in recent times.

The first concerns a problem that turns up time and again, not only on the Internet but also in many books. It is the inability of lots of people to comprehend that there cannot be a year nil, year zero or whatever they choose to call it. (Have patience dear reader the reason will be explained soon). Even worse are the reasons that such people, in their ignorance, dream up to explain the absence of the, in their opinion, missing numberless year. I stumbled across a particularly juicy example on the BBC’s History Extra website last Thursday, in a post entitled, 10 of the most surprising numbers in history. Actually the whole post really deserves a good kicking but for now I will content myself with the authors surprising number, AD 0…  the date that never was. The entry is very short so I’ve included the whole of it below:

The AD years of the Christian calendar are counted from the year of Jesus Christ’s birth, and, as the number zero was then unknown to the west, Dionysius began his new Christian era as AD 1, not AD 0. [my emphasis]

While it is now the consensus that Jesus was probably born between 7 and 3 BC, Dionysius’s new calendar is now the most widely used in the world, while AD 0 is one of the most interesting numbers never to have seen the light of day.

The first time I read this sparking pearl of historical wisdom I experienced one of those extremely painful ‘head-desk’ moments; recovering from my shock and managing at least a semblance of a laugh at this stunning piece of inanity I decided to give it the Histsci Hulk treatment.

Before I explain why there cannot be a year zero, let us look briefly at why Dionysius Exiguus, or Dennis the Short, started his count of the years with AD 1. Dennis, he of little stature, was not trying to create the calendar we use today in everyday lives but was making his contribution to the history of computos, the art of calculating the date of Easter. Due to the fact that the date of Easter is based on the Jewish Pesach (that’s Passover) feast, which in turn is based on a lunar calendar and also the fact that the lunar month and the solar year are incommensurable (you cannot measure the one with the other), these calculations are anything but easy. In fact they caused the Catholic Church much heartbreak and despair over the centuries from its beginnings right down to the Gregorian calendar reform in 1582. In the early centuries of Christianity the various solution usually involved producing a table of the dates of the occurrence of Easter over a predetermined cycle of years that then theoretically repeats from the beginning without too much inaccuracy. Dennis the vertically challenged produced just such a table.

In the time of our little Dennis there wasn’t a calendar with a continuous count of years. It was common practice to number the years according to the reign of the current monarch, emperor, despot or whatever. So for example the year that we know as 47 BCE would have been the third year of the reign of Gaius Julius Caesar. For formal purposes this dating system actually survived for a very long time. I recently came across a reference to a court case at the English Kings Bench Court in the eighteenth century as taking place on 12 July ‘4Geo.III’, that is the fourth year of the reign of George III. In Dennis the Small’s time the old Easter table, he hoped to replace, was dated according to the years of the reign of the Emperor Diocletian (245-311, reigned 284-305). Diocletian had distinguished himself by being particularly nasty to the Christians so our dwarf like hero decided to base his cycle on the 525 532 years “since the incarnation of our Lord Jesus Christ”; quite how he arrived at 525 532 years is not really known. AD short (being short, Dennis liked short things) for Anno Domini Nostri Iesu Christi (“In the Year of Our Lord Jesus Christ”). It was only later, starting with the Venerable Bede’s History of the Church (Historia Ecclesiastica) that Dennis’ innovation began to be used for general dating or calendrical purposes. The idea of BC years or dates only came into use in Early Modern period.

We now turn to the apparently thorny problem as to why there cannot be a year zero in a calendrical dating system. People’s wish or desire to find the missing year zero is based on a confusion in their minds between cardinal and ordinal numbers. (In what follows the terms cardinal and ordinal are used in their common linguistic sense and not the more formal sense of mathematical set theory). Cardinal numbers, one, two, three … and so on are used to count the number of objects in a collection. If, for example, your collection is the cookie jar there can be zero or nil cookies if the jar is, sadly, empty. Ordinal numbers list the positions of objects in an ordered collection, first, second, third … and so on. It requires only a modicum of thought to realise that there cannot be a zeroeth object, if it doesn’t exist it doesn’t have a position in the collection.

This distinction between cardinal and ordinal numbers becomes confused when we talk about historical years. We refer to the year five hundred CE when in fact we should be saying the five hundredth year CE, as it is an ordinal and not a cardinal. Remember our little friend Dennis’ AD, Anno Domini Nostri Iesu Christi (“In the Year of Our Lord Jesus Christ”)! We are enumerating the members of an ordered set not counting the number of objects in a collection. Because this is the case there cannot be a zeroeth year. End of discussion!

That this error, and particularly the harebrained explanation for the supposedly missing year zero, should occur on any history website is bad enough but that it occurs on a BBC website, an organisation that used to be world renowned for its informational reliability is unforgivable. I say used to be because I don’t think it’s true any longer. I would be interested in who is responsible for the history content of the BBC’s web presence as it varies between sloppy as here and totally crap as witnessed here and discussed here and here.

My second example is just as bad in terms of its source coming as it does from the Windows to the Universe website Brought to you by the National Earth Science Teachers Association. You would think that such an educational body would take the trouble to make sure that the historical information that they provide and disseminate is accurate and correct. If you thought that, you would be wrong, as is amply demonstrated by their post on Hellenistic astronomer, Ptolemy.

Ptolemy was a Greek astronomer who lived between 85-165 A.D. He put together his own ideas with those of Aristotle and Hipparchus and formed the geocentric theory. This theory states that the Earth was at the center of the universe and all other heavenly bodies circled it, a model which held for 1400 years until the time of Copernicus.

Ptolemy is also famous for his work in geography. He was the first person to use longitude and latitude lines to identify places on the face of the Earth.

We don’t actually know when Ptolemaeus (Ptolemy) lived, the usual way used to present his life is ‘fl. 150 CE’, where fl. means flourished. If you give dates for birth and death they should given as circa or c. To write them as above, 85–165 A.D. implies we know his exact dates of birth and death, we don’t! This is a trivial, but for historians, important point.

More important is the factual error in the second sentence: He … formed the geocentric theory. The geocentric theory had existed in Greek astronomy and cosmology for at least seven hundred years before Ptolemaeus wrote his Syntaxis Mathematiké (the Almagest). Ptolemaeus produced the most sophisticated mathematical model of the geocentric theory in antiquity but he didn’t form it. Those seven hundred years are not inconsequential (go back seven hundred years from now and you’ll be in 1314!) but represent seven hundred years of developments in cosmology and mathematical astronomy.

The last sentence contains an even worse error for teachers of the earth sciences. Ptolemaeus did indeed write a very important and highly influential geography book, his Geographike Hyphegesis. However he was not “the first person to use longitude and latitude lines”. We cannot be one hundred per cent who did in fact first use longitude and latitude lines but this innovation in cartography is usually attributed to a much earlier Alexandrian geographer, Eratosthenes, who lived about three hundred and fifty years before Ptolemaeus.

This is an example of truly terrible history of science brought to you by an organisation that says this about itself, “The National Earth Science Teachers Association is a nonprofit 501(c)(3) educational organization, founded in 1985, whose mission is to facilitate and advance excellence in Earth and Space Science education” [my emphasis]. I don’t know about you but my definition of excellence is somewhat other.



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

A very similar luminous lustre appears when one observes a burning candle from a great distance through a translucent piece of horn.

On 15 December 1612 (os) Simon Marius, Court Mathematicus in Ansbach, became the first astronomer to record a telescopic observation of the Andromeda Nebula. The importance of this observation was that whereas other known nebulae such as the Orion Nebula, had resolved into individual stars when viewed with a telescope, the Andromeda Nebula as recorded by Marius appears as “…a weak and faint lustre at the centre with a diameter of about one quarter of a degree. A very similar luminous lustre appears when one observes a burning candle from a great distance through a translucent piece of horn” (Simon Marius, Mudus Iovialis, 1614 my translation).

In the history of astronomy the Andromeda Nebula would go on to play a central role in the deep space observations of Charles Messier (M31) and William Herschel in the eighteenth century. In the early twentieth century its nature and status then became the bone of contention in the legendary dispute between Shapley and Curtis.

2014 being the four hundredth anniversary of the publication of Marius’ major astronomical work the Mundus Iovialis we have been celebrating his live and work in Middle Franconia. First high point of the various activities were the launching of the Marius Portal, an Internet website giving researchers free access to all primary and secondary works by and about Simon Marius with navigation in almost thirty different languages.

On 20 September a one-day conference was held with contributions covering the various aspects of Marius’ life and academic work (mathematics, astrology and astronomy) in Nürnberg. The proceedings of this conference are due to appear in book, form hopefully in 2015.

This coming Wednesday, 17 December 2014, will see the founding of the Simon Marius Gesellschaft (Simon Marius Society) in Nürnberg to further research and promote his life and work. Anybody who is interested is herewith cordially invited to apply for full or corresponding membership. There are no membership fees!


Filed under History of Astronomy, History of science, Local Heroes, Renaissance Science

Retelling a story – this time with all the facts

Before 1995 probably only a handful of people interested in the history of navigation had ever heard of the English clockmaker John Harrison and the role he played in the history of attempts to find a reliable method of determining longitude at sea. This situation changed radically when Dava Sobel published her book Longitude: The True Story of a Lone Genius Who Solved the Greatest Scientific Problem of His Time[1] in that year. This volume caught the public imagination and very rapidly became one of the most successful popular history of science and technology books of all time. It was followed just three years later by a lavishly illustrated expanded edition. Just one year after that followed the equally lavish television documentary film based on the book. By the year 2000 at the latest John Harrison had become a household name and a British scientific hero on a level with Newton and Darwin.

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,

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,

All of this would have been well and good if Sobel had actually adhered to the first three words of her subtitle, The True Story…, but unfortunately she sacrificed historical accuracy to the expediency of telling a good story, basically reducing a complex historical narrative to the fairy tale of a poor honest hero, John Harrison, overcoming adversity to finally triumph against the evil machination of his dishonest scheming opponent the Astronomer Royal, Nevil Maskelyne. Sobel’s lurid narrative proved, as already stated, commercially very successful but left its readers with a highly distorted view of what actually took place in the long eighteenth century in the endeavours to find a method of determining longitude and the role that the various people involved played in those endeavours. In particular Nevil Maskelyne was left in the popular public imagination looking rather like the devil’s evil cousin.


Rev. Dr Nevil Maskelyne Source Wikimedia

Rev. Dr Nevil Maskelyne
Source Wikimedia

About five years ago a major historical research project, under the auspices of the Arts & Humanities Research Council, was set up by Cambridge University and the National Maritime Museum in Greenwich on the history of the British Board of Longitude, the official body set up to oversee and direct the search for a method to determine longitude at sea in the eighteenth century. Led by Simon Schaffer for the University of Cambridge and Richard Dunn and Rebekah Higgitt for the National Maritime Museum this project featured a cast of excellent doctoral and post doctoral researchers some of whose findings can be found on the excellent Longitude Project Blog. To date this research project has produced a remarkable list of achievements. Alongside a volume of papers on the much maligned Nevil Maskelyne, which has just appeared and which I am looking forward very much to reading,


the whole of the Board of Longitude archive has been digitized and made available online to researchers. Currently on at the Museum in Greenwich is a major exhibition Ships, Clocks and Stars: The Quest for Longitude, which you can still visit if you hurry, it closes on the 4th of January 2015. If you are uncertain whether or not it’s worth visiting, it has just been awarded the British Society for the History of Science Great Exhibitions Award for 2014! If like myself you are unable for some reason to make the journey to Greenwich do not despair you can bring the exhibition into your own living room by acquiring the accompanying book Finding Longitude: How Ships, clocks and stars helped solve the longitude problem[2] by Richard Dunn and Rebekah Higgitt, a review of which is the actually subject of this post.

Finding Longitude001

My review is actually very simple this book is magnificent. If you have any interest in the histories of navigation, sea voyages, astronomy, clocks, John Harrison, Nevil Maskelyne, Tobias Mayer, and a whole ship’s cargo of other related and interrelated topics then buy this book! I guarantee you that you won’t regret it for one second. It combines thorough research, first class scholarship, excellent writing, unbelievably lavish illustrations, fascinating narratives and historical accuracy in one superb and, for what it is, surprisingly low priced large format volume. Unlike Sobel’s, from a historians standpoint, ill-starred volume, this work really does tell the true story of the solution of the longitude problem with all its complex twists and turns giving all the participants their dues. Although written for the general reader this book should also find a home on the bookshelves of any working historian of navigation, astronomy, horology, sea voyages or just the science and technology of the long eighteenth century.

This book will take you on a voyage through the choppy waters of eighteenth century science, politics and technology and deliver you up on the shores of the nineteenth century much more knowledgeable then you were when you boarded ship and entertain and delight you along the way. It will also make for a first class Christmas present.

[1] Dava Sobel, Longitude: The True Story of a Lone Genius Who Solved the Greatest Scientific Problem of His Time, Fourth Estate, London, 1995

[2] Richard Dunn & Rebekah Higgitt, Longitude: How Ships, clocks and stars helped solve the longitude problem, Collins and Royal Museums Greenwich, London 2014


Filed under Book Reviews, History of Cartography, History of Navigation, History of science

The weather and the stars

My attention was recently drawn to the MacTutor history of maths website article on The History of Weather Forecasting. The article is largely concerned with the mathematics of weather forecasting from the nineteenth century onwards but has some short introductory paragraphs covering the prehistory of meteorology, which unfortunately displays a woeful ignorance of the subject. Under the heading Early Attempts we get served up the following:

It is not known when people first started to observe the skies, but at around 650 BC, the Babylonians produced the first short-range weather forecasts, based on their observations of the stars and clouds. The Chinese also recognised weather patterns, and by 300 BC astronomers had developed a calendar which divided the year into 24 festivals, each associated with a different weather phenomenon. Generally, weather was attributed to the vagaries of the gods, as the wide range of weather gods in various cultures, for example the Egyptian sun god Ra and Thor, the Norse god of thunder and lightning, proves. Many ancient civilisations developed rites such as rain dances and animal sacrifices in order to propitiate the weather gods.

The ancient Greeks were the first to develop a more scientific approach to explaining the weather. The work of the philosopher and scientist Aristotle (384-322 BC) is especially noteworthy, as it dominated people’s views on and their knowledge of the weather for the next 2000 years. In 340 BC, Aristotle wrote his book Meteorologica, where he tried to explain the formation of rain, clouds, wind and storms. In addition, he also described celestial phenomena such as comets and haloes. Many of his observations were — in retrospect — surprisingly accurate. For example, he believed that heat could cause water to evaporate. But he also jumped to quite a few wrong conclusions, such as that winds form “as the Earth exhales“, which were rectified from the Renaissance onwards.

Throughout the Middle Ages and beyond, the Church was the only official institution that was allowed to explain the causes of weather, and Aristotle’s Meteorologica was established as Christian dogma. Besides, weather observations were passed on in the form of rhymes, which are now known as weather lore. Many of these proverbs are based on very good observations and are accurate, as contemporary meteorologists have discovered.

This brief synopsis, which covers approximately one thousand years actually almost completely ignores the main form of weather forecasting practiced throughout the period covered astrometeorology. As any astute reader will have already deduce astrometeorology is a branch of astrology and is in fact astrological weather forecasting. This is one of the more rational forms of astrology; weather comes from the heavens, be it sunshine, fog, wind, or one of the many forms of precipitation (rain, snow, sleet, hail), so it would seem fairly logical to assume that the heaven cause or control the weather. This is exactly what people in antiquity did in many different cultures and actually what the article above is referring to in both of the first two quoted sentences although the author doesn’t seem to or doesn’t want to know it. It was not Aristotle’s views as expressed in the Meteorologica that “dominated people’s views on and knowledge of the weather for the next 2000 years” but astrometeorology. There is a slight irony here as a quote from Aristotle’s Meteorologica delivered one of main justifications for astrology in Western thought up to the Early Modern period. Astrometeorology is along with astro-medicine one of the branches of natural astrology and as such was even accepted throughout the Middle Ages and the Renaissance by people who rejected other forms of astrology, for example judicial or horoscope astrology.

This very widespread acceptance meant that it was astrometeorology that was the dominant form of weather forecasting in the Middle Ages accepted even by the Church at a time when judicial astrology was, at least official, heavily frowned upon. One might well say, so what? What does it matter what people believed before the emergence of scientific meteorology in the seventeenth century, when this superstitious twaddle got drop anyway? The answer is quit simple; astrometeorology played a significant role in the emergence of that scientific meteorology.

During the Renaissance astrology reached its highest level of popularity in the history of Western culture. Almost all mathematicians and astronomers (mostly one and the same) were also practicing astrologers and they were not just doing it for the money as is often falsely claimed by those who try to deny the significance of astrology in the Early Modern period; they really believed in it. However these were the people who also laid the foundations of the modern empirical approach to the sciences and they were often painfully aware of the lack of empirical justification for the science of astrology that they practiced. To counter this weakness they set about developing various projects to give astrology a solid empirical base, one of the principle projects involving astrometeorology. This project consisted of keeping accurate and continuous weather diaries. They thought that by recording the weather over long periods of time on a daily basis they could then distinguish the correlation, that they were sure existed, between the weather and the movement of the celestial bodies. The oldest known such weather diary was kept by Roger Bacon in the thirteenth century. Bacon was of course not only a fervent believer in astrology but also an early proponent of empirical methods in science. There are other scattered medieval weather diaries but the process first really kicked off at the end of the fifteenth century. The keeping of weather diaries was greatly furthered by the introduction of printed ephemerides, which provided the potential meteorologist with a convenient place to record his observations directly next to the astronomical/astrological information for the day.

A notable writer of weather diaries was Johannes Stöfler (1452-1531), who taught and influenced Philipp Melanchthon (a powerful advocate of Renaissance astrology), Sebastian Münster and others. Another was the Nürnberger mathematicus Johannes Werner (1462-1522), who first suggested the chronometer method of determining longitude. Probably most well-known as weather diary keeper was Tycho Brahe (1546-1601), without doubt the important observational astronomer in the pre-telescope era. Tycho is possibly also responsible for David Fabricius (1564-1617), discoverer, amongst other things, of the first variable star, Mira, keeping a weather diary. Fabricius help Johannes Kepler (1571-1630) to formulate his theory of elliptical planetary orbits in an extended correspondence; systematically criticising Kepler various formulations. Kepler a passionate astrologer also kept a weather diary. He famously established his reputation as an astrologer by correctly predicting an especially hard winter in his first prognostications as district mathematicus in Graz in 1594. Weather diaries were also kept by many other less well-known figures. It is significant that Pico della Mirandola (1463-1494) the most strident Renaissance critic of astrology also kept a weather diary and used the results as one of his arguments for rejecting astrology.

Pico della Mirandola was of course right the systematic keeping of weather diaries did not, as hoped, provide an empirical basis for the science of astrology but did exactly the opposite showing that astrometeorology, at least, was a refuted theory. However the results were not all negative. The systematic empirical weather observations contained in the diaries laid the foundations for scientific meteorology in the seventeenth century. The data collected by those Renaissance astrologers is still used by modern meteorologists to help establish long-term weather patterns.




Filed under History of Astrology, History of science, Renaissance Science

Having lots of letters after your name doesn’t protect you from spouting rubbish

The eloquently excellent Elegant Fowl (aka Pete Langman @elegantfowl) just drew my attention to a piece of high-grade seventeenth-century history of science rubbish on the website of my favourite newspaper The Guardian. In the books section a certain Ian Mortimer has an article entitled The 10 greatest changes of the past 1,000 years. I must to my shame admit that I’d never heard of Ian Mortimer and had no idea who he is. However I quick trip to Wikipedia informed that I have to do with Dr Ian James Forrester Mortimer (BA, PhD, DLitt, Exeter MA, UCL) and author of an impressive list of books and that the article on the Guardian website is a promotion exercise for his latest tome Centuries of Change. Apparent collecting lots of letter after your name and being a hyper prolific scribbler doesn’t prevent you from spouting rubbish when it comes writing about the history of science. Shall we take a peek at what the highly eminent Mr Mortimer has to say about the seventeenth-century that attracted the attention of the Elegant Fowl and have now provoked the ire of the Renaissance Mathematicus.

17th century: The scientific revolution

One thing that few people fully appreciate about the witchcraft craze that swept Europe in the late 16th and early 17th centuries is that it was not just a superstition. If someone you did not like died, and you were accused of their murder by witchcraft, it would have been of no use claiming that witchcraft does not exist, or that you did not believe in it. Witchcraft was recognised as existing in law – and to a greater or lesser extent, so were many superstitions. The 17th century saw many of these replaced by scientific theories. The old idea that the sun revolved around the Earth was finally disproved by Galileo. People facing life-threatening illnesses, who in 1600 had simply prayed to God for health, now chose to see a doctor. But the most important thing is that there was a widespread confidence in science. Only a handful of people could possibly have understood books such as Isaac Newton’s Philosophiae Naturalis Principia Mathematica, when it was published in 1687. But by 1700 people had a confidence that the foremost scientists did understand the world, even if they themselves did not, and that it was unnecessary to resort to superstitions to explain seemingly mysterious things.

Regular readers of this blog will be aware that I’m a gradualist and don’t actually believe in the scientific revolution but for the purposes of this post we will just assume that there was a scientific revolution and that it did take place in the seventeenth century, although most of those who do believe in it think it started in the middle of the sixteenth-century.

I find it mildly bizarre to devote nearly half of this paragraph to a rather primitive description of the witchcraft craze and to suggest that the scientific revolution did away with belief in witchcraft, given that several prominent propagators of the new science wrote extensively defending the existence of witches. I recommend Joseph Glanvill’s Saducismus triumphatus (1681) and Philosophical Considerations Touching the Being of Witches and Witchcraft (1666). Apart from witchcraft I can’t think of any superstition that was replaced by a scientific theory in the seventeenth-century. However it is the next brief sentence that cries out for my attention.

The old idea that the sun revolved around the Earth was finally disproved by Galileo.

By a strange coincidence I spent yesterday evening listening to a lecture by one of Germany’s leading historians of astronomy, Dr Jürgen Hamel (who has written almost as many books as Ian Mortimer) on why it was perfectly reasonable to reject the heliocentric theory of Copernicus in the first hundred years or more after it was published. He of course also explained that Galileo did not succeed in either disproving geocentricity or proving heliocentricity. Now anybody who has regularly visited this blog will know that I have already written quite a lot on this topic and I don’t intend to repeat myself here but I recommend my on going series on the transition to heliocentricity (the next instalment is in the pipeline) in particular the post on the Sidereus Nuncius and the one on the Phases of Venus. Put very, very simply for those who have not been listening: GALILEO DID NOT DISPROVE THE OLD IDEA THAT THE SUN REVOLVED AROUND THE EARTH. I apologise for shouting but sometimes I just can’t help myself.

Quite frankly I find the next sentence totally mindboggling:

People facing life-threatening illnesses, who in 1600 had simply prayed to God for health, now chose to see a doctor.

Even more baffling, it appears that Ian Mortimer has written prize-winning essay defending this thesis, “The Triumph of the Doctors” was awarded the 2004 Alexander Prize by the Royal Historical Society. In this essay he demonstrated that ill and injured people close to death shifted their hopes of physical salvation from an exclusively religious source of healing power (God, or Christ) to a predominantly human one (physicians and surgeons) over the period 1615–70, and argued that this shift of outlook was among the most profound changes western society has ever experienced. (Wikipedia) I haven’t read this masterpiece but colour me extremely sceptical.

We close out with a generalisation that simply doesn’t hold water:

[…] by 1700 people had a confidence that the foremost scientists did understand the world, even if they themselves did not, and that it was unnecessary to resort to superstitions to explain seemingly mysterious things.

They did? I really don’t think so. By 1700 hundred the number of people who had “confidence that the foremost scientists did understand the world” was with certainty so minimal that one would have a great deal of difficulty expressing it as a percentage.

Mortimer’s handful of sentences on the 17th century and the scientific revolution has to be amongst the worst paragraphs on the evolution of science in this period that I have ever read.


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