In Our Time

Melvyn Bragg and guests discuss relativism, a philosophy of shifting sands. "Today, a particularly insidious obstacle to the task of educating is the massive presence in our society and culture of that relativism which, recognizing nothing as definitive, leaves as the ultimate criterion only the self with its desires. And under the semblance of freedom it becomes a prison for each one, for it separates people from one another, locking each person into his or her own 'ego'." Pope Benedict XVI, in a speech given in June 2005, showed that the issue of relativism is as contentious today as it was in Ancient Greece, when Plato took on the relativist stance of Protagoras and the sophists. Relativism is a school of philosophical thought which holds to the idea that there are no absolute truths. Instead, truth is situated within different frameworks of understanding that are governed by our history, culture and critical perspective. Why has relativism so radically divided scholars and moral custodians over the centur

Melvyn Bragg and guests discuss prime numbers: 2, 3, 5, 7, 11, 13, 17 … This sequence of numbers goes on literally forever. Recently, a team of researchers in Missouri successfully calculated the highest prime number - it has 9.1 million digits. For nearly two and a half thousand years, since Euclid first described the prime numbers in his book Elements, mathematicians have struggled to write a rule to predict what comes next in the sequence. The Swiss mathematician Leonhard Euler feared that it is "a mystery into which the human mind will never penetrate." But others have been more hopeful... In the middle of the nineteenth century, the German mathematician Bernhard Riemann discovered a connection between prime numbers and a complex mathematical function called the 'zeta function'. Ever since, mathematicians have laboured to prove the existence of this connection and reveal the rules behind the elusive sequence. What exactly are prime numbers and what secrets might they unlock about our understanding of atom

Melvyn Bragg and guests discuss the importance of the oath in ancient Greece and Rome, The importance of oaths in the Classical world cannot be overstated. Kings, citizens, soldiers, litigants all swore oaths, inviting divine retribution if they proved false to their word. Oaths cemented peace treaties, they obliged the Athenian citizenry to protect their democracy, they guaranteed the loyalty of the Roman army to its Emperor and they underpinned the legal systems of Athens and Rome. And in Homer's epic poem, The Iliad, it is a broken oath to settle the dispute between Menelaus and Paris that leads the Greeks to storm Troy in pursuit of Helen. But how did the Classical world come to understand the oath? Why did oaths come to occupy such a central place in the political, social and legal life of the Athenian State? And what role did oath-making play in the expanding Roman Empire? With Alan Sommerstein , Professor of Greek at the University of Nottingham;Paul Cartledge , Professor of Greek History at the Univer

Melvyn Bragg and guests discuss the ‘Oresteia’, the seminal trilogy of tragedies by Aeschylus. The composer Richard Wagner recalled the visceral sensations of reading Aeschylus' great trilogy for the first time. "I could see the Oresteia with my mind's eye ... Nothing could equal the sublime emotion with which the Agamemnon inspired me; and to the last word of the Eumenides, I remained in an atmosphere so far removed from the present day that I have never since been really able to reconcile myself with modern literature." Aeschylus' audience were all familiar with the tale of one man's return home from the Trojan War. Homer's Odyssey recounted Odysseus' perilous journey home, the forceful ejection of the suitors from his household and his reunion with wife Penelope and son Telemachus. Aeschylus had a very different tale of homecoming to tell in his Oresteia. Agamemnon arrives home from Troy to a murderous welcome from a vengeful wife and a cycle of atrocities unfolds in his household. The Oresteia has inspire

Melvyn Bragg and guests discuss ideas of heaven and the afterlife. The great medieval theologian Thomas Aquinas wrote 'that in the end language can only be related to what is experienced here, and given that the hereafter is not here, we can only infer'. Aquinas encapsulated a great human conundrum that has preoccupied writers and thinkers since ancient times: what might heaven be like. And although human language is constrained by experience, this has not stopped an outpouring of artistic, theological and literary representations of heaven. In the early Middle Ages men ascended up a ladder to heaven. In his Divine Comedy, Dante divided heaven into ten layers encompassing the planets and the stars. And the 17th century writer John Bunyan saw the journey of the soul to heaven as a spiritual struggle in his autobiography, The Pilgrim's Progress. But what exactly is heaven and where is it? How does the Protestant conception of the afterlife differ from the Catholic conception? How does one achieve salvation and

Melvyn Bragg and guests discuss the Peterloo Massacre in 1819, a defining moment of its age. In 1819 Percy Bysshe Shelley wrote: 'I met Murder on the way He had a mask like Castlereagh Very smooth he looked, yet grim; Seven blood-hounds followed him: All were fat; and well they might Be in admirable plight, For one by one, and two by two, He tossed them human hearts to chew Which from his wide cloak he drew.' As Foreign Secretary, Castlereagh had successfully co-ordinated European opposition to Napoleon, but at home he had repressed the Reform movement, and popular opinion held him responsible for the Peterloo Massacre of peaceful demonstrators in 1819. Shelley's epic poem, The Mask of Anarchy, reflected the widespread public outrage and condemnation of the government's role in the massacre. Why did a peaceful and orderly meeting of men, women and children in St Peter's Field, Manchester turn into a blood bath? How were the stirrings of radicalism in the wake of the Napoleonic Wars dealt with by the British e

Melvyn Bragg and guests discuss artificial intelligence. Can machines think? It was a question posed by the mathematician and Bletchley Park code breaker Alan Turing and it is a question still being asked today. What is the difference between men and machines and what does it mean to be human? And if we can answer that question, is it possible to build a computer that can imitate the human mind? There are those who have always had robust answers to the questions that those who seek to create artificial intelligence have posed. In 1949 the eminent neurosurgeon, Professor Geoffrey Jefferson argued that the mechanical mind could never rival a human intelligence because it could never be conscious of what it did: "Not until a machine can write a sonnet or compose a concerto because of thoughts and emotions felt", he declared "and not by the chance fall of symbols, could we agree that machine equals brain - that is, not only write it but know that it had written it." Yet the quest rolled on for machines that were

Melvyn Bragg and guests discuss the great 17th century political philosopher Thomas Hobbes who argued: "During the time men live without a common power to keep them all in awe, they are in that condition which is called war; and such a war as is of every man against every man". For Hobbes, the difference between order and disorder was stark. In the state of nature, ungoverned man lived life in "continual fear, and danger of violent death". The only way out of this "solitary, poor, nasty, brutish, and short" existence, he said, was to relinquish all your freedom and submit yourself to one all powerful absolute sovereign. Hobbes' proposal, contained in his controversial and now classic text, Leviathan, was written just as England was readjusting to life after the Civil War and the rule of Oliver Cromwell. In fact, in his long life Hobbes’ allegiance switched from Charles I to Cromwell and back to Charles II. But how did the son of a poor clergyman end up as the most radical thinker of his day? Why did so many o

Melvyn Bragg and guests discuss the search for the Graviton particle. Albert Einstein said "I know why there are so many people who love chopping wood. In this activity one immediately sees the results". Einstein spent the last thirty years of his life trying to find a theory that would unify electromagnetism with gravity, but success eluded him. The search is still on for a unifying theory of gravitational force and hopes are pinned on the location of the graviton - a hypothetical elementary particle that transmits the force of gravity. But the graviton is proving hard to find. Indeed, the Large Hadron Collider at CERN still won't allow us to detect gravitons per se, but might be able to prove their existence in other ways. The idea of the graviton particle first emerged in the middle of the 20th century, when the notion that particles as mediators of force was taken seriously. Physicists believed that it could be applicable to gravity and by the late 20th century the hunt was truly on for the ultimate theor

Melvyn Bragg and guests discuss the American philosophy of pragmatism. A pragmatist "turns away from abstraction and insufficiency, from verbal solutions, from bad apriori reasons, from fixed principles, closed systems, and pretended absolutes and origins. He turns towards concreteness and adequacy, towards facts, towards action and towards power". A quote from William James' 1907 treatise Pragmatism: A New Name for Some Old Ways of Thinking. William James, along with John Dewey and Charles Sanders Peirce, was the founder of an American philosophical movement which flowered during the last thirty years of the nineteenth century and the first twenty years of the 20th century. It purported that knowledge is only meaningful when coupled with action. Nothing is true or false - it either works or it doesn't. It was a philosophy which was deeply embedded in the reality of life, concerned firstly with the individual's direct experience of the world he inhabited. In essence, practical application was all. But how did

Melvyn Bragg and guests discuss the religious orders of the Dominicans and the Franciscans, known as the Blackfriars and Greyfriars. "Just as it is better to light up others than to shine alone, it is better to share the fruits of one's contemplation with others than to contemplate in solitude". Thus St Thomas Aquinas described his vocation, not only as a teacher, but also as a Dominican friar and philosopher at the University of Paris. In the 13th century, the religious orders of the Dominicans and the Franciscans were a great force for change in Catholic Europe. They thrived in the emerging towns and cities of the High Middle Ages, leading crusades and changing the way the Church dealt with heretics. They were the evangelists who transformed the Church's preaching of the Christian message to the people. On top of all this, these two orders were also responsible for reconciling Classical and Christian philosophy; their studies of Aristotle paved the way for the Renaissance. They also managed to change the cu

Melvyn Bragg and guests discuss the unique properties of asteroids. They used to be regarded as the 'vermin of the solar system', irritating rubble that got in the way of astronomers trying to study more interesting phenomena. It was difficult or even impossible for an observer of asteroids to book time using the world's best telescopes, because they were regarded as unspectacular objects that could tell us little about the origins of the universe. However, that has all changed. It is now thought that asteroids are the unused building blocks of planets, 'pristine material' that has remained chemically unchanged since the creation of the solar system; a snapshot of matter at the beginning of time. At the moment the Japanese probe Hayabusa is 180 million miles away, pinned to the back of the asteroid Itokawa, attempting to gain our first samples of the chemical composition of an asteroid. Why did asteroids fail to form planets? How do they differ from their celestial cousins, the comets? And are either of them

Melvyn Bragg and guests discuss Samuel Johnson, a giant of 18th century literature. “There is no arguing with Johnson, for when his pistol misses fire, he knocks you down with the butt of it." The poet Oliver Goldsmith was not alone in falling victim to the bludgeoning wit of Samuel Johnson. The greatest luminaries of 18th century England, including the painter Joshua Reynolds, the philosopher Edmund Burke and the politician Charles James Fox, all deferred to him... happily or otherwise. Samuel Johnson was credited with defining English literature with his Lives of the Poets and his edition of Shakespeare, and of defining English language with his Dictionary. Yet despite those lofty acclamations he failed to get a degree, claimed he had never finished a book, was an inveterate hack who told his friend James Boswell, "No man but a blockhead ever wrote, except for money". How did an Oxford drop-out become England's most famous and well connected man of letters? How did generations of readers come to see him as

Melvyn Bragg and guests discuss the Cynics, the performance artists of philosophy. Eating live octopus with fresh lupins, performing intimate acts in public places and shouting at passers by from inside a barrel is behaviour not normally associated with philosophy. But the Cynics were different. They were determined to expose the meaninglessness of civilised life by action as well as by word. They slept rough, ate simply and gave their lectures in the market place. Perhaps surprisingly, their ideas and attitudes were immensely popular in the ancient world. But how coherent was cynicism as a philosophy? What was its influence on literature and politics and is there any truth to the contention that Jesus himself was influenced by the Cynics? With Angie Hobbs, Lecturer in Philosophy, University of Warwick; Miriam Griffin, Fellow of Somerville College, Oxford; John Moles, Professor of Latin, University of Newcastle.

Melvyn Bragg and guests discuss the rise of the mammals. The Cenozoic Era of Earth's history began 65 million years ago and runs to this day. It began with the extraordinary 'KT event', a supposed asteroid impact that destroyed the dinosaurs, and incorporates the break up of Pangaea, the enormous landmass that eventually formed the continents we know today. It is known as the 'Age of the Mammals', and it is the period in which warm-blooded, lactating, often furry animals diversified rapidly and spread across the globe on land and in the sea. According to evolutionary theory, what conditions created the opportunity for mammals to thrive? What environmental factors lead to the characteristics they share - and the features they don't? And how did they become the most intelligent class of animals on the planet? With Richard Corfield, Senior Lecturer in Earth Sciences at the Open University; Steve Jones, Professor of Genetics at University College London; Jane Francis, Professor of Palaeoclimatology at the Univers

Melvyn Bragg and guests discuss the Field of the Cloth of Gold, an extraordinary international party. In the spring of 1520 six thousand Englishmen and women packed their bags and followed their King across the sea to France. They weren't part of an invasion force but were attendants to King Henry VIII and travelling to take part in the greatest and most conspicuous display of wealth and culture that Europe had ever seen. They were met by Francis I of France and six thousand French noblemen and servants on English soil in Northern France and erected their temporary palaces, elaborate tents, jousting pavilions and golden fountains spewing forth red, white and claret wine in the Val D'Or. For just over two weeks they created a temporary town the size of Norwich, England's second city, on the 'Camp du Drap D'Or', or Field of the Cloth of Gold. What drove the French and the English to create such an extraordinary event? What did the two sides do when they got there, and what - if anything - was achieved? With Ste

Melvyn Bragg and guests discuss the history of magnetism. Pliny the Elder, in his Historia Naturalis, tells a story of a legendary Greek shepherd called Magnes who, while guiding his flock on Mount Ida, suddenly found it hard to move his feet. The nails of his sandals held fast to the rock beneath them, and the iron tip of his crook was strangely attracted to the boulders all around. Magnes had stumbled across the lodestone, or 'Magnetite', and discovered the phenomenon of magnetism. Plato was baffled by this strange force, as were Aristotle and Galen, and despite being used in navigation, supposedly suspended over the body of Mohammed and deployed in the pursuit of medical cures. St Thomas Aquinas thought magnets had souls. it was not until the late 16th century that any serious scientific attempt was made to explain the mystifying powers of the magnet. Descartes developed a particle theory of magnetism but the great Isaac Newton fought shy of the problem of what caused magnets to attract and repelWho pione

Melvyn Bragg and guests discuss Karl Marx. "Workers of the World Unite! You have nothing to lose but your chains", "Religion is the opium of the people", and "From each according to his abilities, to each according to his needs". That should be enough for most of you to work out whom Radio 4 listeners have voted as their favourite philosopher: the winner of the In Our Time Greatest Philosopher Vote, chosen from 20 philosophers nominated by listeners and carried through on an electoral tidal wave of 28% of our 'first-past-the-post' vote is the communist theoretician, Karl Marx.So, when you strip away the Marxist-Leninism, the Soviet era and later Marxist theory, who was Karl Marx? Where does he stand in the history of philosophy? He wrote in his Theses on Feuerbach, "Philosophers have only interpreted the world in various ways, the point, however, is to change it" - which begs the question, is he really a philosopher at all?With Anthony Grayling, Professor of Philosophy at Birkbeck College, University of Londo

Melvyn Bragg and guests discuss Christopher Marlowe. In the prologue to The Jew of Malta Christopher Marlowe has Machiavel say:"I count religion but a childish toy, And hold there is no sin but ignorance. Birds of the air will tell of murders past! I am ashamed to hear such fooleries.Many will talk of title to a crown. What right had Caesar to the empire? Might first made kings, and laws were then most sure When, like the Draco's, they were writ in blood."A forger, a brawler, a spy, a homosexual and accused of atheism but above all a playwright and poet, Christopher Marlowe was the most celebrated writer of his generation, bringing Tamburlaine, Faustus and The Jew of Malta to the stage and far outshining William Shakespeare during his lifetime. Then came his mysterious death at 29, days before he was due to appear on trial accused of heresy. Was he stabbed in an argument over a bill? Was he assassinated? And how does his work measure up to Shakespeare, a man who paid generous tribute and some say stole some o

Melvyn Bragg and guests discuss the legendary wizard Merlin. He was sired by an incubus and born of a virgin; he was a prophet, a shape-shifter, a king-maker and a mad man of the woods. Before Gandalf there was Merlin: the power behind Arthur and a literary sensation for centuries. In a literary career spanning 1500 years, Merlin, or originally Myrddin, put the sword in the stone, built Stonehenge, knew the truth behind the Holy Grail and discovered the Elixir of Life. "Beware Merlin for he knows all things by the devil's craft" say the poisoners in Malory's Morte D'Arthur; but he is also on the side of the good and is almost Christ-like in some of the versions of his tale, and his prophesies were pored over by the medieval Church. Who was Merlinus Ambrosius, as he is sometimes known? Where does his legend spring from and how has it been appropriated and adapted over time?With Juliette Wood, Associate Lecturer in the Department of Welsh at Cardiff University, Stephen Knight, Distinguished Research Professor i