"Uncertainty" by David Lindley

This is the best account of the history of the development of quantum physics that I have read. 

The story of how Heisenberg came up with his uncertainty principle, charting the demise of determinism in physics, from the prehistory of Brownian motion, through the first stirrings of radioactivity and quantum physics by Becquerel and Rutherford and Planck and Einstein, through the Bohr model of the atom to the alternative versions of quantum mechanics proposed by Heisenberg and Schrodinger. Having taught physics for 34 years, I was familiar with the concepts and much of this history but this book (written by an old house mate of mine from student days) is a hugely lucid account of how a remarkably small group of people constructed some revolutionary and philosophically difficult theories. It clearly shows their contributions and explores the human side of their interactions, as well as giving due credit to some of the other key players with whose names we are less familiar today, such as Eastbourne's own Frederick Soddy, de Broglie, Born and Bohm, Compton and Pauli and Sommerfield. It also shows what a ridiculous own goal Hitler scored when he expelled key 'non-Aryan' scientists, hugely impoverishing German science; an own goal the Brexiteers seem determined to want to repeat.

Selected quotes:

• "Dead particles of dust clearly couldn't move of their own volition, nor was any external influence pushing them around. Yet move they all too plainly did. ... Faced with this impossible dilemma, science took the prudent course and ignored Brownian motion for decades." (Ch 1) Brown's book about this is mentioned in Middlemarch!
• "Because he developed in Munich a lifelong habit of staying out late at bars and cafes, Pauli generally missed morning lectures." (Ch 6)
• "Heisenberg had ... depicted the electron's physical presence as a combination of things it might be doing, rather than some specific indication of where it was." (Ch 11)
• "In his crazed desire to promote Aryan culture and safeguard Germany from noxious foreign influences, Hitler succeeded in the space of just a few years in destroying Germany's preeminent position in physics." (Ch 14)
• "Schools of science, as of art or music, rarely stay for long in one place." (Ch 15)
• "Spengler's method is to lay out reams of detail and weighty quantities of obscure facts, and then, as the reader's head begins to nod, to leap adroitly to grand assertions about what it all must mean." (Ch 15) I have noticed a similar technique with writers in the earth-mysteries genre such as von Daniken: they 'leap adroitly to grand assertions about what it all means' having puzzled the reader with perplexing mysteries; I call this the 'wow-thus' argument. But it's not much different in philosophy; some philosophers spend 90% of their books using detailed and sometimes nit-picking scrutiny to demolish each system of their opponents undermining all of the reader's previous beliefs, until the reader is desperate for some sort of ground on which to stand, at which point they rush out their own, virtually unexamined, grand system. 
• "Uncertainty did not erupt capriciously in the mid-1920s. It had been welling up for a decade or more already by then, forcing itself upon the reluctant consciousness of scientists." (Ch 15)
• "In the rise of uncertainty in Germany ... there's an irreducible element of contingency ... In this respect scientific history is like history in general." (Ch 15)
• "For most philosophers, though, loosey-goosey won't do." (Ch 17)

This is the best account of the history of quantum physics I have read. It is one of the books on which Benjamin Labatut based his misleading collection of fictionalised biographies 'When we cease to understand the world'. Readers interested in this topic would be well advised to read Philip Ball's Beyond Weird which provides an update into the concepts which is as understandable as I have ever found a book about this difficult topic. 

Other books on Science and Scientists which are reviewed in this blog may be found on this page.

November 2022; 222 pages

This review was written by the author of Bally and Bro, Motherdarling  and The Kids of God

"Beyond Weird" by Philip Ball

This book is about quantum physics. It contains all the usual suspects: wave-particle duality, the Heisenberg Uncertainty Principle, Schrodinger's Cat, the Many Worlds Interpretation. According to Ball these are fundamentally inadequate attempts to view the quantum world - which underpins (and is coherent with) the everyday world - in images that rely on everyday understandings. He throws in some of the modern research on entanglement, superposition, wavefunction collapse and decoherence. And, in the end, he concludes that possibly, quantum physics is a theory of information.

It is a comprehensive overview of the field and, so far as I can judge, it is fair to all the many different interpretations of what quantum physics means. It even asks whether the theory is ontic (dealing with reality) or epistemic (dealing with what we know). I found it tough going in places and there are some bits that I still don't understand (and I used to teach quantum physics at secondary school level). But there were other moments when Ball's explanations led me a significantly deeper understanding than I had before and for that I can only be grateful. And impressed. If he can deliver even a little greater understanding about this tough subject, it is a remarkable achievement.

Selected quotes:

• “Quantum theory ... is a theory about information. ... it asks what a theory of knowability can look like.” (p16)
• “What do we mean by ‘is’? ... As for what an electron ‘is’, all we can talk about for sure is what we can see and measure.” (p60)
• “Everything that seems strange about quantum mechanics comes down to measurement. If we take a look, the quantum system behaves one way. If we don’t, the system does something else.” (p78)
• “Niels Bohr ... wasn’t naturally gifted as a writer - he would draft and redraft endlessly without much obvious benefit to the prose.” (p104)
• "Whatever the question, the answer is ‘Yes’ (unless it’s ‘No’)" (chapter heading)
• “Quantum mechanics might seem ‘weird’, but it is not illogical. It’s just that it employed a new and unfamiliar logic ... with different customs and traditions and with its own beautiful internal consistency.” (p128)
• “It is not obvious why any of the properties that things have at the everyday scale should remain meaningful properties at the microscopic scale. Some don’t. Electrons don’t have a colour.” (p129)
• “No one fully understands how quantum computers work.” (p278)
• “In science ... it’s as worthwhile for an idea to be productive as it is for it to be ‘right’.” (p285)
• “Might it be that non-locality is simply in the nature of things, and relativity is the only thing that limits its influence?” (p309)
• “There’s no guarantee that the world’s innermost workings will fit a language developed mostly to conduct trade, courtship and banter.” (p324)

October 2022; 354 pages

Other books reviewed in this blog about science and scientists can be found here. 

This review was written by the author of Motherdarling  and The Kids of God

"The Map that Changed the World" by Simon Winchester

 Simon Winchester also wrote The Surgeon of Crowthorne about a homicidal maniac who made a significant contribution to the Oxford English Dictionary while detained in a mental hospital.

This book is about William Smith, son of a blacksmith, who created the world's first geographical map and virtually invented single-handed the science of stratification, being the first man to realise that fossils could be used to date sedimentary rocks. It is also a tale of a snobbish Georgian upper-class closing ranks against this ill-bred man and consigning him to bankruptcy, debtor's jail, and ignominy before recognising his genius. It's a great story, well-written, which hardly ever flags (though I perhaps didn't want to know quite so much about Oolitic Limestone). 

Smith was born in 1769, the year that Josiah Wedgwood opened the 'Etruria' pottery near Hanley, the year that James Watt patented the first condensing steam engine, and the year that Richard Arkwright made the first water-powered spinning frame. It was also the time when agriculture was improving in productivity by leaps and bounds, following the Enclosure Acts, resulting in boom in population which made it clear that Britain couldn't feed its people. 

The book is filled with wonderful pen portraits of remarkable characters, albeit cameo roles in Smith's drama:

• The Duke of Bridgewater, who started the canal craze by building one from his coalfields to Manchester to ship his coal: "He was at first widely disliked. As a young man he was irredeemably philistine, with little regard for art or society. He dressed intolerably badly. He loathed flowers and all kinds of ornamentation. He smoked like industrial Manchester, consumed pounds of snuff, never wrote letters, had arguments with everyone.  ... He was a curmudgeonly bachelor and a misogynist who so despised women that he would even allow one to serve him at table." (Ch 4)
• John Farey, who started as the steward of the Duke of Bedford at Woburn, "became an expert musician (and a chorister of note), a mathematician whose work (on the curious proerties of vulgar fractions) is still known today, and a contributor to encyclopaedias on such topics as astronomy, engineering, the history of pacifism, the design of steam-engines, the decimalization of currencies and the population theories of Thomas Malthus." (Ch 12)
• "William Wollaston  was ... said by all to be a man blessed with the most acute powers of observation. He could apparently see the tiniest of flowers while riding on horseback. He invented the camera lucida after noticing something odd in the crack in his shaving mirror. He was one of the few men who ever noticed a mirage on the River Thames. He was doctor, an expert on kidney stones and on mineral-based enlargements of the prostate." (Ch 17)

And there is a roll-call of other interesting people who were associated with Smith, from the Duke of Bedford to Selina Hastings, from Adam Sedgwick to Roderick Murchison. from Sir Joseph Banks to Louis Agassiz who invented the concept of the ice age.

Selected quotes:

• "It has long been said that the people of England could never be poor, since they lived on an island made of coal, and surrounded by fish." (Ch 4)
• "Adelard, 'England's first scientist', a twelfth -century philosopher who had written treatises on the abacus and the astrolabe, had been born in Bath." (Ch 9)

September 2022; 299 pages

Other books on the History of Science and Biographies of Scientists can be found here.

This review was written by the author of Motherdarling  and The Kids of God

"Raising the Dead" by Andy Dougan

A history focused on the medics and scientists who tried to reanimate dead people using electricity, both before and after the publication of Frankenstein. This book focuses particularly on the work of Andrew Ure, a Glaswegian anatomist, who experimented on the newly-hanged cadaver of condemned murdered Matthew Clydesdale in November 1819, months after the publication of Mary Shelley's novel, but it also looks at previous work, for example by Galvani and his nephew Aldini, both of whom believed in 'animal electricity', and by Mary Shelley's husband, the poet Percy Bysshe Shelley, who was an amateur electrical experimenter and a believer in Paracelsus and a follower of the work of Humphrey Davy, who invented electrolysis. Gruesome as it was, this work has led to the invention of the defibrillator.

For me there was too much emphasis on the Ure-Clydesdale experiment (we have a full description of the murder and the trial) and not enough on the science, but the later chapters contained plenty of interest.

Selected quotes:

• “Graham would deliver lectures on sexual satisfaction as his Goddesses of Youth and Health, a succession of barely-clad, nubile young things, worked the crowd encouraging them to part with their cash.” (Ch 7)
• “Shelley continued to read Humphrey Davy and ... remained convinced that ‘electrical fluid’ was the all-animating force of life and could hold all of its secrets. He referred to the human body as a lump of electrified clay.” (Ch 7)
• “Positive electricity made vision sharper and red-hued while negative electricity made it blurred and bluish.” (Ch 9)

August 2022; 201 pages

The Age of Wonder by Richard Holmes also considers the scientists who might have inspired Frankenstein but he settles for Johann Wilhelm Ritter (1776 - 1810)

This review was written by the author of Motherdarling  and The Kids of God

"The Glass Bathyscaphe" by Alan Macfarlane and Gerry Martin

Perhaps I missed it. I don't remember reading anything about a glass bathyscaphe (a power underwater craft made mainly of glass). I checked the index: no bathyscaphe is mentioned. The title seems to refer only to the illustration on the cover. The book is focused entirely on its subtitle: 'How Glass Changed the World'.

Glass-making has been around for a long time in Eurasia but its early use was almost entirely ornamental, using opaque, coloured glass. Thin transparent glass requires glass-blowing techniques, developed “somewhere in Syria or Iraq” in c100 BCE (Ch 2). The authors carefully distinguish various uses of glass as ornaments, vessels, windows and mirrors and suggest that it was the fact that glass windows were so useful in the cold climates of northern Europe (enabling people to work indoors; there were glass windows in Britain during the Roamn occupation)  that led to the emphasis on transparent glass which is so useful for the key scientific instruments that were essential for the scientific revolution (not just see-through (and heat-proof and inert) reaction vessels for chemistry but also thermometers, barometers, vacuum-pumps, telescopes and microscopes, not to mention lanterns, sextants and chronometers to assist sea travel and even light bulbs.

As well as science, the authors consider the effect of glass on art, particularly the development of perspective, which they suggest, with evidence from contemporary sources, was facilitated by the use of mirrors. They also suggest that windows encouraged paintings because both are framed and show how some early renaissance artists used panes of glass as drawing aids.

They further hypothesise that the western European cult of individuality was encouraged by glass mirrors; they suggest the rise of autobiographies correlates with the rise of glass mirrors.

They even suggest that the reason the scientific revolution did not take place in East Asia was because they never developed spectacles. The book theorises that this is because they have much higher rates of myopia than in western Europe. They hypothesise that this is because (a) the traditional rice and vegetable diet contains too little vitamin A and (b) they have a strong literary tradition, with young children forced to learn a large number of literary texts from a very early age; the resultant eye strain causes myopia. But myopia in young children is an eye defect among the relatively economically powerless so there was no need for spectacles (and a short-sighted person can still read by putting their face very close to the page); furthermore the gradual increase in long-sightedness as people age would mean that older people didn’t need spectacles. In contrast, the eye defect in the west was predominantly long-sightedness which makes it nearly impossible to read and this stimulated the demand for spectacles.

This is therefore an ambitious work! The arguments are persuasive although I was rarely convinced; perhaps a smaller focus and a greater depth of evidence would have sealed the deal. Nevertheless, it was an entertaining read. But where was the bathyscaphe?

Selected quotes:

• “Discovery sometimes comes after a first rough set of guesses has begun to seem plausible enough to justify detailed examination.” (Ch 1)
• “A world of continuous investigation and assessment of nature and social relations, has many enemies. Most human beings prefer certainty and order above all else. Most innovations and change threaten such orderliness. In particular, new ideas can be subversive and dangerous. Much of history shows the tendency of thought systems to close down, solidify, and put up increasing barriers to disturbance. ... One aspect of this is what might be termed roughly the tendency towards inquisitorial thought. ... ‘Heresies’ are now rooted out; challenges to the thought system are seen as threats to the social and political order. The thought police are active, but do not need to be called in because of self-emasculation by individuals under all sorts of pressures, including those of loved ones. ... Whether it is the Jesuits or the Mandarins or the Mullahs, a strict enforcement of the notion the certain ideas must not be challenged becomes widespread. It is more important to learn the old truths and reinterpret them than to learn new ones.” (Ch 3) 
• “This curiosity, the impetus to test and speculate, the sense that there were expanding horizons of knowledge, that not all was known and there were new worlds to be discovered, were boosted by the rapidly expanding wealth and technology of the period. The new burst of power through the intensive exploitation of wind, water and animals, the growth of trade and cities, and the expansion of Christianity ... encouraged experimentation.” (Ch 3)
• “Glass shifts authority from the word, from the ear and the mind and writing, to external visual evidence. The authority of elders is challenged; the test is the individual eye and the authority of the doubt-filled and sceptical individual.” (Ch 4)
• “At the two ends of Eurasia very different cosmologies and ideologies developed ... at one end of the continent a glass civilisation emerged, and at the other a pottery and paper one.” (Ch 6)
• “It is one of the ironies of life that just as they reach the peak of knowledge, in their late forties and fifties, many people find it impossible to continue reading without glasses.” (Ch 8)
• “The invention of spectacles in creased the intellectual life of professional workers by fifteen years or more. ... The revival of learning from the fourteenth century onwards may well be connected to this. ... The active life of skilled craftsmen, often engaged in very detailed close work, was also almost doubled.” (Ch 8)

July 2022; 213 pages

This review was written by the author of Motherdarling  and The Kids of God

"Wizard: The Life and Times of Nikola Tesla" by Marc J Seifer

Tesla was, to say the least, eccentric. Perhaps he was "the quintessential mad scientist" (C 45). Perhaps he was a misunderstood genius; perhaps he was a charlatan. In this odd biography Seifer attempts to write  "the biography of a genius."

Born a Serb in Croatia, Tesla studied in Serbia and Paris before making his way to New York to work for Edison. He was fascinated by electricity, in particular by electromagnetic induction in which a changing magnetic field induces electric current to run through a wire. This is the fundamental principle used in generating electricity, it is used to transform voltages up and down, and it is used in creating electromagnetic waves which enable you to send electrical signals from transmitter to receiver by electromagnetic waves, including radio waves.

When he arrived in New York he was a pivotal player in the 'battle of the currents': Edison championed direct current (dc) electricity; Westinghouse was in favour of alternating current (ac); the great advantage of ac is that it can be easily transformed to very high voltages which can be transmitted with negligible loss of power over great distances and then transformed down to safe usable voltages; it is the basis for most modern grid systems. Tesla had realised as a young student that ac had an advantage over dc in that an ac  generator doesn't need a component called a commutator as a dc generator does. Tesla was therefore an ac convert and his invention of three-phase ac, after leaving Edison and setting up as an independent inventor,  was the key component of the Westinghouse victory.

One of the grisly side-issues in the battle of the currents was Edison's attempt to brand ac as more dangerous than dc by having it employed to execute prisoners. An Edison associate called Brown manufactured electric chairs and experiment on electrocuting animals and sought employment as a prison executioner. The first prisoner to be capitally punished by electrocution was subjected to a drawn-out, much bungled affair. (C 6)

This led to fame and fortune for Tesla who began a lifetime habit of living in hotels, hobnobbing with rich and famous (John Jacob Astor III (as well as being one of the richest men in the world at the time he was a bit of an inventor including "a bicycle brake ... a storage battery, an internal-combustion engine, and a flying machine"; C 17), John Pierpoint Morgan and many luminaries of the science world), working all hours to come up with even more exciting inventions and writing patents, and fighting patent litigation battles against other inventors he claimed were pirating his patents (or those who claimed they had priority over him). The intricacies of the patent battles, fully described in the book, are a bit of a yawn.

As a very young man Tesla invented the Tesla coil, a coil of wire used to produce high-voltage high-frequency ac electricity and a key component in the early wirelesses. Thus, he claimed priority over Marconi, who used a Tesla coil in his early wirelesses. Tesla also claimed to have invented the ability to transmit much further using ground waves. Marconi's triumph in their endless battles over patents and priorities embittered Tesla and, perhaps, turned him from eccentric to madman. As a succession of investors discovered before pulling out, Tesla's Leonardo-like inability to focus on a single project to completion and his inability to produce something merely good, led to a succession of never-actually abandoned projects. His work degenerated into showmanship and endless promises of revolutionary new designs and world-beating systems which were incomparably better than anything yet seen but never actually materialised. This was the polar opposite of the Edison system of 1% inspiration and 99% perspiration (Tesla criticised Edison by saying "If he had a needle to find in a haystack he would not stop to reason where it was most likely to be, but would proceed at once with the feverish diligence of a bee, to examine straw after straw"; C 4) and Tesla, for all his genius, for all his spent his mature years dodging from hotel to hotel, his bills unpaid, sponging off friends, pleading for funds, and feeding pigeons.

The biography embodies the restless energy of Tesla, his chaotic lifestyle and his eccentric approach to life. I was surprised when, about half-way through, it moved from a conventional approach to quoting conversations verbatim; some of these are clearly 'reconstructed'; it is as if it has become a novel based on the life of Tesla at these points. For me the biography failed to make sense of the chaos of Tesla's life and it certainly failed to explain in a way I could understand and appreciate the physics behind Tesla's inventions (and I taught Physics for 33 years so I have some idea of electromagnetism). The moments it came alive were in the sympathetic portrayal of the character of the man, especially in old age, his triumphs forgotten, still working hard to pay his debts, still working hard to persuade investors of the value of his latest scheme.

In the end, Tesla was a bit of a loony. These tendencies started early when he seemed to be claiming that some of his nearly perpetual-motion systems used energy very similar to 'vril' the mysterious force invented by Lord Lytton in a work of fiction called 'The Coming Race' which became a favourite of occultists and led to a drink called Bo-Vril. When studying Hertzian electromagnetic waves he decided the Hertz was wrong and that radio waves were longitudinal. (C 11)His pursuit of perpetual motion disregarded the laws of thermodynamics; later he claimed to have invented particles and waves that travelled faster then light in defiance of Einstein's relativity: "the various discoveries and suggestions inherent in Tesla's theory violate not only accepted theories such as relativity and quantum physics but also, on the surface, common sense." (C 44)

This looniness went a bit sour when he became a devotee of eugenics: "Tesla supported the idea of 'sterilizing the unfit and deliberately guiding the mating instinct'." (C 46) He himself was. probably, celibate. "Tesla denied himself certain pleasures as a way to supposedly establish total control over himself. And yet Tesla was a complete slave to his idiosyncrasies and to a cauldron of phobias." (C 46)

There are also plenty of other weirdos, such as Abraham Spanel, an Odessan Jew who fled Russian pogroms in 1905 and ended up as president of the International Latex Corporation in Delaware, now Playtex.

Some brilliant bits:

• "Other bogus inventors of the day included Gaston Bulmar who tried to sell General Electric (GE) special pills that turned water into gasoline." (C 7)
• "Michael Pupin ... wanted to go to Cambridge to learn under James Clerk Maxwell, but he found upon his arrival that Maxwell had been dead for four years." (C 8)
• "For exercise, the inventor would walk '8 - 10 miles per day' ... Later, Tesla would add to his repertoire the squishing and unsquishing of his toes one hundred times for each foot each night." (C 43)
• Tesla said: "I'll never be rich unless the money comes in the door faster than I can shovel it out the window." (C 44)

June 2020; 470 pages

"The Double Helix" by James D Watson

The classic account of the discovery of the double helix structure of DNA for which Watson and Francis Crick won a Nobel Prize. This account is a real warts-and-all account of scientific discovery. Watson regularly admits he doesn't understand the maths for some of the work, and that he is a poor experimenter who blew up a Chemistry lab by heating Benzene using a Bunsen burner. He seems to spend most of his time thinking about pretty girls which is a feature he has in common with almost all of the other young men researching science. His sexist and misogynist attitudes make for difficult reading nowadays even if, in the epilogue to this memoir, he concedes that the by then dead Rosalind Franklin was a superb experimenter whom he greatly undervalued and that her behaviour, which he regularly considers unacceptable, might possibly have been a consequence of the difficulty facing women trying to be first class research scientists in those days.

Watson and Crick are neither supposed to be working on DNA (indeed Crick's boss Bragg has angrily told himk to concentrate on finishing his thesis and Watson is misusing the his funding which is for a different problem at a different Uni in another country!) but they keep tinkering with models. Nothing seems to be working. They (and everyone else except, it seems, Franklin) are convinced that the structure is helical but is in one, two, three, four or five strands twisted together. They and the rival groups working on the same problem are convinced that the backbone of sugars and phosphates is in the inside. But when Franklin's photo B clearly reveals helicity Watson starts to develop a two-strand model, which allows replication, and starts to think of the strands as held together by the bases. He assumes the bases are paired and that Adenine is held to Adenine by hydrogen bonds, as are Thymine to Thymine, Cytosine to Cytosine and Guanine to Guanine. Then a chemist friend tells him that the structures he is using are of the wrong isomers. Using the right isomers means that this like-to-like pairing (AA, CC, TT and GG) makes the essential double helix buckle; it would no longer be fundamentally crystalline. Furthermore there would be no reason why experimental results showed, as they did, that there was always the same amount of adenine and thymine and of cytosine as guanine, even though the ratios of A to C or T to G might vary. "Suddenly I became aware that an adenine-thymine pair held together by two hydrogen bonds was identical shape to a guanine-cytosine pair held together by at least two hydrogen bonds." A double helix structure in which the ladder steps are A-T or C-G explained why the proportions of A and T are always the same as well as explaining the X-ray crystallography data. And a quest as exciting as any Hollywood blockbuster is complete.

Other moments:
"One could not be a successful scientist without realizing that ... a goodly number of scientists are not only narrow-minded and dull, but also just stupid." (C 2)
After Crick had so upset his boss he had been ordered to stop work on DNA: "News of the upset confirmed the fact that Francis might move faster if occasionally he closed his mouth."
On getting a textbook for a Christmas present. "The remnants of Christianity were indeed useful."
On discovering a co-worker in his room with a girl: "The presence of popsies does not inevitably lead to a scientific future."

Lively and entertaining. February 2019; 128 pages

"From the Closed World to the Infinite Universe" by Alexandre Koyre

This is from the 'Easy Reading Series' of Forgotten Books: it is relatively easy to read but the format which fails to easily distinguish between extensive quotations and the author's gloss makes it much more difficult to read than it should be.

Koyre is concerned with the change of world view which occurred about the same time as the Copernican revolution.

He starts with the arguments of Nicholas of Cusa who "denies the finitude of the world and its enclosure by the walls of the heavenly spheres" (p 8) although he won't go so far as to assert the infinity of space, only that the universe is 'interminate', "it is boundless and not terminated by an outside shell" (p 8) but also that it "utterly lacks precision and strict determination" (p 8) so it can never reach the limit; he reaches this conclusion by using his doctrine of '"learned ignorance" (p 8) "the intellectual act ... which transcends discursive, rational thought". He illustrated this by pointing out that an infinitely large circle has straight sides (the curved side at any point will coincide with its tangent) and an infinitely small circle will also have straight sides (the side will correspond to its radius) and that therefore the big infinite and the little infinite are the same.

Unfortunately Koyre does not really explain 'learned ignorance'; I had to find Wikipedia to tell me: "docta ignorantia means that since mankind can not grasp the infinity of a deity through rational knowledge, the limits of science need to be passed by means of speculation. This mode of inquiry blurs the borders between science and ignorantia. In other words, both reason and a supra-rational understanding are needed to understand God. This leads to the coincidentia oppositorum, a union of opposites, a doctrine common in mystic beliefs from the Middle Ages."  https://en.wikipedia.org/wiki/De_Docta_Ignorantia

Next he talks about a poetic philosopher named Palingenius who uses the Principle of Plenitude (again unexplained but which is the idea that God is so brilliant that all possible forms of creation are available in the world) to deny "the finitude of God's creation" (p 21).

Koyre continues to Copernicus which he says "undermined the very foundations of the traditional cosmic world-order with its hierarchical structure and qualitative opposition of the celestial realm of immutable being to the terrestrial or sublunar region of change and decay." (p 23) He points out that "the immediate effect of the Copernican revolution was to  spread scepticism and bewilderment" (pp 23 - 24) Perhaps the most convincing Copernican argument was the fact that it would take much more effort to make the large sphere of the fixed stars rotate than the much smaller Earth.

There is also a chapter on Giordano Bruno, who asserted the infinity of the heliocentric Universe and was burnt at the stake. But he wasn't that modern or perhaps he was, he asserted that since the senses were flawed and could be fooled the intellect was primary.

Then, via Galileo, comes Descartes who starts with the idea of God and therefore starts with infinity and derives the finite from the idea of the infinite. Typically weird. You start to understand where the other French philosophes have got it from.

We next get several chapters on Henry Moore, a Neo-Platonist who disputed with Descartes and taught Newton and therefore a fascinating and often overlooked philosopher of nascent science. He pointed out the daftness of Descartes endeavour to avoid the void because nothing can come of nothing as Lear might have said. |Moore suggests that the primary property of matter is not its extension but its impenetrability; he asks how "can a purely spiritual soul ... which, according to Descartes, has no extension whatever, be joined to a purely material body, that is to say something which is solely and only extension?" By exposing the contradictions inherent in the ramshackle Cartesian system which endeavours to solve scientific problems through the appeal to a wholly biased intellect, Moore laid the foundations for Newtonian science. And for infinity. Because Descartes believed that the Universe was bounded. But Moore asked: "Could Descartes not tell what would happen ... if somebody sitting at the extremity of the world pushed his sword through them limiting wall? On the one hand, indeed, this would seem easy, as there would be nothing to resist it; on the other, impossible, as there would be no place where it could be pushed." (p 89)

Moore, Koyre tells us, was a syncretist who tried to synthesise the new discoveries with the occult, magical and hermetic traditions nut nevertheless "succeeding in grasping the fundamental principle of the new ontology, the infinitization of space." (p 93) And such dabbling in weird stuff was necessary to develop the theory of, for example, gravity. This has a challenging principle of action at a distance. "Gravity cannot be explained by pure mechanics" (p 98) Koyre points out.

And so from Moore to Newton and, in particular, his letters to Mr Richard Bentley in which he states that "the cause of gravity is what I do not pretend to know"; nevertheless Newton realises that he can analyse its effects without knowing its causes. (p 131).

This is an interesting book but it would be an easier read if (a) some of the Latin tags were translated (I managed to work out most of them but I was taught Latin forty five years ago) and (b) if Koyre explained some of the things he mentions such as the Principle of Plenitude.

May 2017, 200 pages

"Science in a Free Society" by Paul Feyerabend

Feyerabend's thesis is that rationalism has too firm a grip on society and that the best medicine is a little anarchy.

He defines rationalism as "a secularized form of the belief in the power of the word of God." (p 20) which believes itself to be "'objective' and tradition-independent" but he suggests that although modern society bases itself on science "as uncritically as one once accepted the cosmology of bishops." (p 74) it is just another tradition fighting for itself in a world of alternative traditions. No tradition, he asserts, can judge another tradition because the values and beliefs of each tradition are different; this is a form of Kuhn's incommensurability thesis. You can't even damn a tradition on the basis that it is internally contradictory. Contradictions are not necessarily signs of a weak argument. The idea "that we do not live in a paradoxical world" so that our "knowledge must be self-consistent ... loses it authority the moment that we find that there are facts whose only adequate description is inconsistent and that inconsistent theories may be fruitful."

OK. These are serious issues. We have to acknowledge that science is 'just' another tradition and that it is difficult to make an objective judgement about whether as a tradition is is one of the best. But Feyerabend then appears to assert that this difficulty therefore means that anything ought to go.

He asserts that "a free society is a society in which all traditions are given equal rights, equal access to education and other positions of power." (p 30). Thus Hopi creation myths should be taught alongside the Big Bang Theory, astrology with astronomy, homeopathy with scientific medicine (he doesn't like scientific medicine!). Thus far he is relativist; he is also anarchist is the sense that "rules have their limit" (p 32) though he probably doesn't go on to assert that "all rules and standards are worthless and should be given up." (p 32). 

He appears to advocate the Socratic view that everything should be examined (although he places a significant restriction on the ability to examine if we can only examine any one tradition from inside). But Feyerabend does not appear to examine his basic assumption which seems to be that we 'should' live in a 'free' and 'democratic' society. 

Because if he is right that a 'free' society must give all traditions equal rights then it would follow that a 'free' society must give "equal rights, equal access to education and other positions of power" to 'traditions' such as racism and Nazism and Aztec human sacrifice. I don't think I want to live in such a society.

The second half of the book is dedicated to vitriolic attacks on those who have dared to criticise him, suggesting that he has been misunderstood. He seems hurt by the violence of the reaction to what he thinks are reasoned views but the section in which these protestations are made is entitled "Conversations with illiterates" which doesn't sound either friendly or reasoned. 

Some interesting points but the overall conclusions seem ridiculous. September 2016; 217 pages

"The Strangest Man" by Graham Farmelo

This is the biography of Paul Dirac, the mathematical physicist whose work, with Heisenberg laid the theoretical foundations of quantum theory, who synthesised quantum physics and special relativity to develop quantum electrodynamics, and who predicted the positron and anti-matter. He shared the Nobel Prize with Schrodinger and was, at the time, the youngest recipient of the Physics prize.

He was famously taciturn; so much so that fellow students invented a unit called the dirac to represent the smallest imaginable amount of conversation, one word per hour.

He was also famously scruffily dressed. I used to cite him as an example whenever people came up with the dictum "Dress smart, think smart."

I was inspired to read this book having read the brilliant The Fly in the Cathedral by Brian Cathcart which explores the background to Cockcroft and Walton splitting the atom. The Strangest Man is a stunning biography. Not only does Farmelo manages to make quantum physics accessible, at least in its generalities; not only does he describes the intoxicating excitement of the early days of discovery with Heisenberg and Einstein and Schrodinger, when Gottingen University was one pole and Bohr's Copenhagen the other; but he also charts the dreadful consequences of the Second World War, when Schrodinger had to hide in Dublin having initially endorsed Nazism, when Dirac's best friend Kapitza was kept in Moscow by Stalin, always fearing that Beria might arrest him and have him killed, when Heisenberg was working for the Nazis and Bohr was in occupied Denmark, and Dirac's sister, an Englishwoman married to a Jew, was in occupied Amsterdam. Then there are the days of McCarthyism when Dirac's left wing politics had him banned from America while his friend Oppenheimer, who had led the atom bomb project, had his security clearance revoked.

And in particular, this biography centred on the human that was Dirac, the survivor of a horrible childhood in which his life and that of his mother who became a slave in her own home and Dirac's brother who killed himself, and Dirac's sister who gave up on life to stay quietly at home until Dirac managed to free her to go to University were all the victims of a terrible father, a bully, an adulterer, a tax cheat, and a man who tried in vain to understand the difficult stuff that his brilliant son was doing.

Then comes Dirac's marriage to a lively tempestuous woman, the polar opposite of the taciturn man he himself was. He acquired two step-children (his step-daughter disappeared in America, her car found abandoned) and fathered two children of his own. His marriage had its rocky patches. They were too different. And he must have struggled not to be like his own father. But the marriage survived.

This was a stunning portrait of a brilliant mind. Read it!

August 2016; 438 pages

There is a BBC Radio 4 In Our Time programme about Paul Dirac; it was broadcast on 5th March 2020

In detail:

Dirac had a dreadful childhood. His father was a disciplinarian teacher who bullied his family. Paul was made to eat dinner with his father and to speak only French (his father was Swiss); he was often sick. Paul's elder brother Felix committed suicide (which devastated the father so he was loving if a bully); his sister stayed at home after being schooled and did nothing; the mother became an unpaid servant for the father, kept on a pittance (although he was clearly a lot richer than he admitted) and was told by him after thirty years of marriage that he had never loved her; she then discovered he had been having at least one long term affair. In short, the father was a nasty piece of work.

Paul was forced to study engineering at Bristol University; he was two years younger than the other students; having graduated Bristol arranged for him to take a maths degree and skip the first year. But he almost never got to Cambridge because his father was unwilling to find the necessary money for Paul to afford to live. It was only once he got to Cambridge as a graduate student that he started to fill in some of the huge holes in his knowledge, partly by taking extra geometry classes on Sunday afternoon in the Arts School when, apart from him and the other students having tea and being taught, and a few cleaners, the building was "as lifeless as a museum at midnight". (p 72)

He cultivated a straight-talking, straight-writing, plain English prose style following George Orwell's dictum that "Good prose is like a windowpane." (p 75)

Even Dirac was subject to failing to see when he was on the trail of something. When he first met de Broglie's idea that a particle such as an electron could act like a wave he "carried out some initial calculations but put the work aside after concluding that he had done nothing worth publishing. Having sniffed the scent of an important problem, he had then lost it; but he would soon return." (p 81)

His first breakthrough was recognising that the rather complex maths in Heisenberg's first formulations of quantum theory, being non-commutative, reminded him of Poisson's brackets: "Fifty two years later, he remembered, 'The idea first came in a flash, I suppose, and provided of course some excitement'" (p 86) Brackets were important to Dirac. Having invented a new mathematical notation for quantum physics which involved two halves of a bracket (which he called the bra and the ket) he later told a discussion at high table in St John;s on neologisms that "I invented the bra". Being taciturn he then relapsed into silence for the rest of the meal. (p 326)

When Oppenheimer was having a nervous breakdown at the Cavendish he tried to poison his teacher, Blackett, by leaving him an apple laced with chemicals. (p 97) Shades of Snow White and Alan Turing! When he defended his PhD thesis to examiners Franck and Born Franck later said: "I'm glad that is over. He was on the point of questioning me." (p 133)

Even Albert Einstein struggled "to understand his [Dirac's] peculiar combination of logic and intuition" telling a friend "This balancing on the dizzying path between genius and madness is awful." (p 114)

He hypothesised the positron (which he called an anti-electron; a later suggestion from California was 'oreston' because Electra's brother was Orestes) because he "followed the logic of Sherlock Holmes: 'When you have eliminated all which is impossible then whatever remains, however improbably, must be the truth.'" (p 187) (Doyle 1926, The Adventure of the Blanched Soldier). We are still in a world where the imbalance of matter over anti-matter of just one part in a billion after the Big Bang cannot really be explained but "without that imbalance, the matter and anti-matter formed at the beginning of time would have annihilated each other immediately, so that the entire universe would only ever have amounted to a brief bath of high-energy light. Matter would, in that case, never have had an opportunity to discover anti-matter." (p 434)

Farmelo quotes Stephen Spender talking about young Germans after the great inflation: "their aims were to live from day to day; and to enjoy to the utmost everything that was free: sun, water, friendship, their bodies." (p 121)

The big band (OK, that's a typo, but it sounds so much better than the big bang) theory of the universe was first proposed by a Belgian cleric, the Abbe Lemaitre "who believed that the Bible teaches not science but the way to salvation" (p 261)

Despite a long bachelorhood lasting beyond thirty, Dirac flirted with Gamow's wife Rho and later got involved with Wigner's sister, Hungarian born Manci, who became his wife (although he described her as "Wigner's sister" even after the wedding. They had a long courtship conducted often by letter. When she complained he didn't answer her questions he numbered her letters and wrote a table of (often brutally) honest responses leading her to complain that some of the questions he had now answered were rhetorical! (p 262) As he grew closer to marriage his parents' relationship fell apart. His father told his mother he had not loved her for thirty years (predating Dirac's birth) and his mother discovered that his father had been engaging in long-term affairs (after he died she also discovered that he had been systematically cheating the taxman so he wasn't just miserly with her). But Dirac's marriage to Manci, though often tempestuous (at least on her part, he greeted her moods with indifference which must have infuriated her even more) did last. "She once snapped at him when he was eating his dinner, 'What would you do if I left you?' only for him to reply - after a half-minute pause - 'I'd say "Goodbye dear"'" (p 366)There is a photo of him on the beach at Brighton on his honeymoon in his suit "pencils still protruding from the pocket of his jacket" (p 284)

He was intrigued by the coincidental ratios of force strengths to one another and to the dimensions of the Universe and hypothesised that this might be because the strength of gravity is inversely proportional to the age of the Universe (which would explain why it is expanding but rather upsets the standard estimates of such things as the age of the Earth). (p 290)

He became Fred Hoyle's supervisor "partly because he was amused at the prospect of a relationship between a supervisor who did not want a student and a student who did not want a supervisor" (p 295)

He disliked the idea of electrons as point sources because that would involve infinities in such things as electric field strengths. But I would have thought that quantum mechanics does not allow points; they are forbidden by Heisenberg; a particle that was a point would have an infinite momentum,

He believed mathematical beauty was more important than experimental evidence.

As he got older he was more often challenged by "the drawn sword of youth". (p 321) As Oscar Wilde said in 1887 "In America, the young are always ready to give those who are older than themselves the full benefit of their inexperience." (p 332)

During the Second World War he worked on the separation of the fissile U-235 isotope from its chemically identical and much more abundant non-fissile U-238; he invented a series of methods including centrifuges. (p 321)

After Einstein's death, Dirac became "the most famous loner in theoretical physics, an elderly rebel with a cause that no one else could quite understand." (p 355) He then developed a primitive version of string theory.

Page references refer to the 2010 Faber and Faber paperback edition

The Fly in the Cathedral" by Brian Cathcart

From its very beginning, relating the 1909 discovery of Rutherford alpha particle scattering in which a final year undergraduate named Ernest Marsden saw something that contradicted all previous theories of the atom, Cathcart manages to capture both the tedium of live research science (Marsden has to follow a procedure including sitting in a darkened room for 20 minutes before taking observations; when he sees the 'wrong' thing he spends a week checking and rechecking every part of his apparatus before becoming certain of his results) and the excitement of discovery.

From there, Cathcart explains how Ernest Walton arrived at the old Cavendish laboratory in Cambridge where the world famous Rutherford resided (I had lectures there when an undergraduate in a lecture theatre which James Clerk Maxwell designed but most of the building at the time had been sealed off because it had been contaminated by the experiments of Rutherford and his team). This was 1927 when the laboratory was not as fertile as the glory days before the first world war and there was a certain pressure on all involved to make more ground-breaking discoveries. But to attack the nucleus would need particles moving extraordinarily fast so that they could overcome the electrostatic repulsion of the nucleus, so Walton, working with John Cockcroft, started to build a particle accelerator. Given that the National Grid was in its infancy, using transformers to up ac to the hundreds of thousands of volts they believed they needed and then building rectifiers and vacuum tubes capable of standing these high voltages without either bursting or electrocuting the experimenters (Walton had to crawl across a wooden floor to approach the wworkign apparatus) was a formidable technical challenge made possible mostly by Cockcroft who, having served with distinction in the war,  had previously worked with Metropolitan Vickers the electrical engineering company in Manchester (where my wife's gradnfather worked).

A number of other experimenters in the US were working on the same ideas, notably Tuve using a static generator designed by his friend Van der Graaf, and Tuve's childhood friend Ernest Lawrence who was building a cyclotron. Nuclear disintegration was also being studied by Joliot and Curie (the daughter) in Madame Curie's lab in Paris, and by Otto Hahn and Lise Meitner in Berlin.

And the quantum theorists were kicking off. The 1920s were the glory days of Rutherford's old buddy Nils Bohr in Copenhagen, and Werner Heisenberg and Max Schrodinger in Germany. Louis de Broglie's 1924 theory of wave particle duality was being discussed and an amazingly enterprising Russian named Gamow turned up one day at Bohr's lab in Copenhagen. Bohr was busy and Gamow was given an appointment in a few days time but after he explained he only had money to survive a single day the secretary took pity on him and he saw Bohr that afternoon who immediately arranged for him to stay. Gamow then worked out that wave function particles could penetrate the nucleus at much lower energies.

But Walton and Cockcroft toiled at their apparatus, evacuating tubes that leaked and sealing the leaks with Bank of England sealing wax (they later found that plasticine did a better job) for several years.

At this stage everyone knew that the atoms was composed of electrons orbiting (in set orbits) a very tiny nucleus which had protons in it. But the nucleus must also have either neutrons (Rutherford's theory) or electrons. The electrons were the favoured theory because beta radiation involves electrons leaving the nucleus; neutrons were purely speculative and scarcely mentioned in polite circles. So when Curie and Joliot discovered radiation flowing from a beryllium target that had been bombarded with radiation from polonium, everyone assumed that the neutral rays must be gamma rays even though they packed much more of a punch than seemed possible for gamma rays. But Chadwick, Rutherford's deputy at the Cavendish, revived the neutron theory and showed that they radiation was a stream of neutrons. This was in February 1932. Almost immediately a grumpy Rutherford told Cockcroft and Walton that they had better stop tinkering with their apparatus in an attempt to improve it and use it to fire protons at something. They set up a lithium target, fired the protons in and immediately discovered, still using the scintillation technique that Marsden had used, alpha particles.

Over the next few weeks they frantically repeated their results and worked out the implications whilst sworn to secrecy (Walton told his girlfriend, Cockcroft his wife, Rutherford told Bohr). The disintegration was caused because the protons were absorbed into the lithium nucleus which then spolit into two alpha particles. This was happening at a far lower energy than they had expected, partly because protons do the 'quantum tunnelling' described by Gamow at significantly lower energies than alpha particles but also because the quantum tunnelling is a probabilistic effect and they were generating millions more protons than had been available with the old techniques of relying on radium sources to emit alpha particles. Another 'problem' was that the alpha particles had higher energies that the energies of the incoming protons but this was resolved when it was realised that two alpha particles have a lower mass than a lithium nucleus and a proton and than this mass loss was being converted into energy through Einstein's most famous equation: E=mc2. They had split the nucleus.

This is a wonderful tale of impoverished graduate students in a worldwide fraternity working with string and sealing wax to do cutting edge research. Cathcart writes brilliantly, the tale fairly bowls along, and gives full play to the human stories behind the geeks.  The excitement of the times is vividly captured as is the hard work necessary and the oddness of the characters.

This is a fabulous book. It appears to be out of print. Why??????

July 2016; 274 pages

Cathcart also wrote The News from Waterloo about how the news of the Battle of Waterloo reached London. 

Another brilliant book about this time is The Strangest Man by Graham Farmelo which tells the story of quantum theorist Paul Dirac.

Other books about the history of science or scientific biographies, which are reviewed in this blog, may be found here.

This review was written by the author of Motherdarling  and The Kids of God

"Against Method" by Paul Feyerabend

Feyerabend is a firebrand, an iconoclast, whose purpose is to demolish any theory that seeks to systematise the processes of scientific discovery. He starts with the statement that "anarchism, while perhaps not the most attractive political philosophy, is certainly excellent medicine for epistemology, and for the philosophy of science" (p 1). The history of science is "complex, chaotic, full of mistakes, and entertaining." (p 3) And he continues to challenge throughout the book. Don't be misled by the italics, which he peppers with the abandon of a Caribbean chef. This is not the work of an obsessed dilettante. He is thoroughly immersed in the history of science and proceeds to provide extensive evidence from the Copernican revolution.

Although it is a little worrying, given his tendency to make broad-brush statements such as "There is not a single interesting theory that agrees with all the known facts in its domain" (p 14; my emphasis), that the evidence he cites comes exclusively from the Copernican revolution (with a little bit added in about Newton but he rarely strays into biology or chemistry or even quantum physics).

His essential thesis is that scientists are mavericks who don't assess theories in terms of the facts they can explain (and certainly, despite Popperianism, don't reject theories because they are falsified by inconvenient facts). Nor do scientists neatly construct methodologies. Indeed, in Feyerabend's eyes, the process of scientific discovery is an essentially ad hoc muddle of methodological innovation, new philosophical insights and perspectives, and facts. In order for science to make progress it is necessary, from time to time, to flout the rules of scientific methodology. (p 7) "Inventing theories and contemplating them in a relaxed and 'artistic' fashion, scientists often make moves that are forbidden by methodological rules." (p 150)

This is an interesting book and contains many insights into the work of Galileo in particular. He can get carried away: "his natural sense of humour and not the inbred and always rather nasty kind of jocularity one finds in specialized professions" combines yet another of his italicisings with the naturalistic fallacy with a sweeping generalisation ('always') and bitchiness. But on the whole it is well written, with reams of footnotes (some pages have more footnote than text) and tons of well-argued evidence.

I often do not read the Appendices of books. Hence, having reached Appendix One, I put the book down and wrote the blog post above. Then, for some reason, I took the book back up and discovered that there were five more chapters after Appendix One (including, interspersed, Appendix Two). And a Post Script. That really is it. So below is the rest of the blog post.

The remaining chapters investigate the processes involved when two inconsistent ideas interact, which is where he differs from Thomas Kuhn who his classic Structure of Scientific Revolutions has suggested that paradigms can be so different as to be incommensurable with no possibility of interaction. Feyerabend believes that "Incommensurability depends on covert classifications." (p 171) and he defines "Covert classifications are sensed rather than comprehended." (p 170) This means that when, for example,an iconoclastic young Turk in, say, theatre despairs of the theatre of his time and, by searching outside the box, promotes a revolution in drama, his new revolutionary school can and does interact with the old school which may "lead to a slight modification of the original practice, it may eliminate it, it may result in a tradition that barely resembles either of the interacting elements." (p 224) This is a very common-sense view.

But his overall argument, summed up in his title Against Method, is that "all rules have their limits" although "I do not argue that we should proceed without rules and standards" (p 242). He uses a nice analogy which will even work in the sat nav era: "The wanderer uses the map to find his way but he also corrects it as he proceeds ... Using the map no matter what will soon get him into trouble. But it is better to have maps than to proceed without them." (p 233)

But one of the reasons why a single uniform method should not be imposed is that we are always seeking to explore hitherto unmapped regions. "We don't know the region, we cannot say what will work in it." Fair point, although one suspects that the human reaction will be to try to apply whatever has worked so far.

He's right of course. Scientists don't follow their own rules. Who does? Exploration must always involve a great deal of making-it-up-as-you-go-along. We should not try to discern, still less impose, a single Method on research. That is just common sense. But Feyerabend's gift for communication sometimes makes him seem more like a prophet than a philosopher, more of an iconoclast than an academic, and ever so slightly a crank. When he seems to suggest that physics as a way of discovering the universe is not as good as mysticism, it is easy to see why his opponents should accuse him of an 'anything goes' platform when actually his 'anarchy' is merely a plea against totalitarianism.

June 2016; 287 pages

"What is this thing called science?" by A F Chalmers

This is an extremely readable account of the history and philosophy of science. He explains some difficult ideas with brilliant clarity.

He talks about the problem of induction, expressed by Bertrand Russell as the problem the turkey faces when, following daily examples, he induces that he is always fed at 9AM ... until he discovers he is wrong on Christmas Eve. Furthermore, since what you see depends on what you expect, in some sense theory comes before observation; Chalmers illustrates this rather neatly with an example about junior doctors learning to see what the weird marks on X-rays actually mean.

He then discusses Popperian ideas about falsificationism at length and shows the weaknesses of this theory.

He then looks at alternative accounts of the historical development of Physics from the point of view of Lakatos, Kuhn and Feyerabend.

For me, the most important moments came when he was talking about concept networks. He argues that "the Newtonian concept of mass" is more precise than "the concept of democracy" (pp 77 - 78) because "the concept plays a specific, well-defined role in a precise, structured theory." (p 78). "If this suggested close connection, between precision of a term or statement and the role played by that term or statement in a theory, is valid, then the need for coherently structured theories follows fairly directly from it." (p 78). For example, a dictionary definition requires one to understand many other words. He also quotes Feyerabend as asserting the importance to Copernicus of the "internal connectedness" of the parts of his system. (p 103)

This of course links to the idea that Kuhn viewed "normal science as a puzzle-solving activity" (p 92) and, putting coherence above correspondence, stated that "puzzles that resist solution are seen as anomalies rather than as falsifications of the paradigm." (p 92)

But Chalmers also provides a justification which I can use for my choice of Grounded Theory as a methodology for exploring liminality: "Precise experimentation can only be carried out if one has a precise theory capable of yielding predictions in the form of precise observation statements." (p 79) and since Galileo was creating a new paradigm "it need not be surprising that his efforts involved thought experiemtns, analogies and illustrative metaphors rather than detailed experimentation." (p 79)

This is a well written and readable account of the history of physics though perhaps a little out of date with the latest ideas.

April 2016; 170 pages

"Sapiens" by Yuval Noah Harari

The real beauty of this book is that it is written in very clear, very accessible, very simple language. It explains ideas and concepts. And it covers 2 million years of human history in 466 pages.

The inevitable downside of all this simplicity and brevity and clarity is that it admits no uncertainty. There is no suggestion that the ideas it presents may be controversial, that even the facts it offers are interpretations of evidence about which there are often fundamental disagreements.

For example, on page 55 he states that there is "some evidence that the size of the average Sapiens brain has actually decreased since the age of foraging." (p 55) Fair enough. But he then builds speculation on this evidence as if it were a fact. Human brains have decreased in size because agriculture opened up "niches for imbeciles".  One of his great themes is how well adapted humans were to a hunter-gatherer lifestyle and how much more miserable agricultural peasants were than their forebears.

He defines religion as "a system of human norms and values that is founded on belief in a superhuman order" (p 255) and thus he claims that Buddhism and Marxism are religions even though they deny the supernatural. I would classify religions as systems of beliefs that accept the supernatural and thus I would deny that either Buddhism or Marxism are religions. He doesn't argue the point, he just states his definition and that is that. Later he says "if it makes you feel better, you are free to go on calling Communism an ideology rather than a religion" but that just made me feel patronised! Presumably science, in that the Laws of Nature are 'superhuman' and that  a scientist is likely to have a world view with human norms and values embedded into it (such as Occam's razor) qualifies as a religion. Hmm.

Another example: On page 266 he states that "one of the distinguishing marks of history as an academic discipline" is that "historians tend to be sceptical of ... deterministic theories." Yet this comes at the end of several pages when he is arguing that empires inevitably grow.

I mean, I like the idea that: "Capitalism's belief in perpetual economic growth flies in the face of nearly everything we know about the universe. ... The human economy has nevertheless managed to keep on growing throughout the modern era, thanks only to the fact that scientists come up with another discovery or gadget every few years." (p 352) But is this a fact or Mr Harari's opinion?

I have grumbled enough. Such a wide sweep over world history in such an accessible book inevitably requires short cuts. On balance, Sapiens is a delightful book with lots of brilliant insights. I agree with most of his claims above. I also thoroughly enjoyed the insights below.

• Chimpanzees have a hierarchical structure in which less dominant grunt and grovel to the alpha male (p 28)
• The Maoris only reached New Zealand 800 years ago; almost immediately the islands' mega-fauna became extinct. (p 74): We are not the first generation to drive other species out of existence.
• Wheat "domesticated Homo sapiens, rather than the other way around". (p 90)
• "From a biological perspective, nothing is unnatural. Whatever is possible is by definition also natural." (p 164) Some things are forbidden in our culture but they are not 'unnatural'
• "Every man-made order is packed with internal contradictions." (p 182) For example, the values of equality and freedom inevitably contradict one another (p 183) "Cognitive dissonance is often considered a failure of the human psyche. In fact, it is a vital asset. Had people been unable to hold contradictory beliefs and values , it would probably have been impossible to establish and maintain any human culture." (p 184) Eg God and the devil. Logically, monotheists cannot admit a dualistic belief such as the devil (p 247)
• History is a "level two chaotic system" (p 267) because predictions made by historians are likely to affect the outcome (the weather is a level 1 chaotic system because weather forecasts won't affect what the weather is ,unless we start seeding clouds etc). He suggests that this is likely to make historians "prophets who predict things that don't happen" (p 268)!
• Cultures are "a kind of mental infection or parasite, with humans as its unwitting host", carried by memes (p 270)
• "Ardent capitalists tend to argue that capital should be free to influence politics, but politics should not be allowed to influence capital." (p 367)
• "It is chilling to contemplate what might have happened if Gorbachev had behaved ... like the French in Algeria." (p 414)
• Many of us act like a man on the beach trying to welcome good waves and push back bad waves. Buddhists suggest we should behave like a man who "sits down on the sand and just allows the waves to come and go as they please." (p 442)

Read this book. It is beautifully written and full of important ideas (but remember that they are ideas, not holy writ). November 2015; 466 pages

"Big Bang" by Simon Singh

This is a delightful and fascinating history of cosmology up to and slightly after the near-universal (pun not intended) acceptance of the Big Bang theory of the creation of the Universe. Having taught Physics for 33 years I knew most of the Science and understood the arguments but there were still aspects I had not fully appreciated. These were carefully explained and I am confident that this book would be accessible to the general reader. Singh also explained the philosophical issues and weighed up the various arguments carefully so that their merits and demerits could be easily compared. But the icing on the cake was his affectionate portrayal of the very human astronomers and cosmologists who contributed to (or fought against) our present understanding.

There were so many characters. Here are just a few:

• Fritz Zwicky, for example, was famously rude. His favourite insult was to call you a 'spherical bastard' because,just like a sphere, he thought you were a bastard whichever way he looked at you. 
• Lord Rosse owned an estate in Ireland and gave up astronomy to look after his tenants during the Irish Potato Famine; he built a huge telescope on his lands but was rather foiled by the fact that there are two sorts of weather in Ireland: raining and about to rain. 
• Walter Baade, a German emigre in USA during the Second World War experienced similar frustrations when the authorities decided that, as an enemy alien, he should be confined to his house between sunset and sunrise despite working on the Mount Wilson optical telescope. 
• George Gamow, a practical joker, who had to defect from the USSR; his first attempt involved trying to canoe across the Black Sea which he had to give up after two days. 
• Fred Hoyle, the proponent of the Steady State Theory, who shot himself in the foot not once but twice: first when he developed the theory for nucleosynthesis which removed a significant problem for the Big Bang theory and secondly during a radio broadcast when he scornfully referred to what was then called the dynamic evolving model as a Big Bang, thus creating a catchy name to popularise the idea.

The book ends with a short epilogue in which the continuing issues facing cosmology are outlined. Why is the expansion of the Universe apparently accelerating? What is the mysterious dark energy that might explain this? Why are the six numbers that govern the Universe so perfectly aligned that humans can exist? Does this mean that we are just one bubble in a multiverse? And most of all, of course: What happened before the Big Bang?

A thought-porvoking book that takes you for a ride through the mysteries of the Universe and yet explains them so well that you understand some reallt difficult science.

April 2015; 493 pages

Other books by this author:

• Fermat's Last Theorem: I have not yet read this
• The Code Book: I very much enjoyed this history of cryptography
• The Simpsons and Their Mathematical Secrets: a fun book about Maths which I have reviewed in this blog

"The Structure of Scientific Revolutions" by Thomas Kuhn

I first read this book, which was published in 1962, when I was studying the History and Philosophy of Science at Cambridge in 1987-8. It was a revolutionary thesis. This is the third edition (1996) which adds a postscript to respond to some of the issues that its original publication raised.

Science, Kuhn suggests, does not make steady progress closer and closer to the truth. Rather, it is oscillates between a 'normal' phase during which scientists solve problems and a 'revolutionary' phase when scientific certainties are thrown out of the window and a radically different understanding is born.

He calls the framework within which normal science is done a 'paradigm' and the revolution a 'paradigm shift'. There are many similarities between the way science develops during a paradigm shift and the way students learn if we assume the 'threshold concepts' theory of learning.

For example, In the 1880s physicists were complacently expecting that soon their classical models would be able to explain all that needed to be explained. They were refining them and making them a little more accurate. There were a few clouds on the horizon. Maxwell's equations suggested that light was an electromagnetic wave but no one could detect the 'aether', the postulated medium through which the e-m waves must ripple. The 'ultra-violet catastrophe' was the theoretical model of the atom which predicted that when you heated something up it should glow purple before it glowed red and at some stage it would radiate infinite amounts of energy in the ultra-violet part of the spectrum. And the photo-electric effect was an experiment which suggested that the energy of the electrons emitted from a surface when light was shone on it was not linked to the brightness of the incoming light. But these were blips and no-one seriously doubted that classical physics would soon be able to solve these problems.

In fact the failure to detect the aether was explained once Einstein had discovered his theory of Special Relativity with its bizarre claims that the speed of light was the fastest possible speed, the simultaneity was relative, that time slowed down as you got faster and that mass and energy were inter-convertible. The ultra-violet catastrophe gave rise to the weird world of Quantum Physics and the photoelectric effect was the key evidence for wave-particle duality which shortly led to de Broglie's claims that particles could behave like waves.

In some ways this makes Science a little like the pile of sand as explained in the book Ubiquity. As grain after grain is added to the pile it becomes more and more unstable. Sometimes there are slight slips; at other times there are near-catastrophic landslides.  Or science is like the punctuated equilibrium model of evolution as described in John Gribbin's brilliant Deep Simplicity. Most of the time evolution just contributes a little variation which make organisms marginally better adapted to their evolutionary niches. But when there is a major ecological catastrophe, evolution goes wild to fill the new ecological niches that have been created.

Kuhn writes with elegance and power. This is a very convincing thesis that had a major impact on the history and the philosophy of Science.

March 2015; 210 pages