Melvyn Bragg and his guests discuss Malthusianism.In the eighteenth century, as expanding agriculture and industry resulted in a rapid increase in the European population, a number of writers began to consider the implications of this rise in numbers. Some argued it was a positive development, since a larger population meant more workers and thus more wealth. Others maintained that it placed an intolerable strain on natural resources.In 1798 a young Anglican priest, the Reverend Thomas Malthus, published An Essay on the Principle of Population. Malthus argued that the population was increasing exponentially, and that food production could not keep pace; eventually a crisis would ensue. He suggested that famine, disease and wars acted as a natural corrective to overpopulation, and also suggested a number of ways in which humans could regulate their own numbers. The work caused a furore and fuelled a public debate about the size and sustainability of the British population which raged for generations. It was a profoundly influential work: Charles Darwin credited Malthus with having inspired his Theory of Natural Selection.With:Karen O'BrienPro-Vice-Chancellor for Education at the University of BirminghamMark PhilpLecturer in Politics at the University of OxfordEmma GriffinSenior Lecturer in History at the University of East Anglia Producer: Thomas Morris.

Melvyn Bragg and his guests discuss one of the most famous statements in philosophy: "Cogito ergo sum".In his Discourse on the Method, published in 1637, the French polymath Rene Descartes wrote a sentence which remains familiar today even to many people who have never heard of him. "I think", he wrote, "therefore I exist". Although the statement was made in French, it has become better known in its Latin translation; and philosophers ever since have referred to it as the Cogito Argument.In his first Meditation, published ten years after the Discourse, Descartes went even further. He asserted the need to demolish everything completely and start right again from the foundations, arguing, for instance, that information from the senses cannot be trusted. The only thing he could be sure of was this: because he was thinking, he must exist. This simple idea continues to stir up enormous interest and has attracted comment from thinkers from Hobbes to Nietzsche and Sartre. With:Susan JamesProfessor of Philosophy at Birkbeck College, University of LondonJohn CottinghamProfessor Emeritus of Philosophy at the University of Reading and Professorial Research Fellow at Heythrop College, University of LondonStephen MulhallProfessor of Philosophy at the University of Oxford.Producer: Thomas Morris.

In the 500th edition of the programme, Melvyn Bragg and his guests discuss the philosophical idea of free will.Free will - the extent to which we are free to choose our own actions - is one of the most absorbing philosophical problems, debated by almost every great thinker of the last two thousand years. In a universe apparently governed by physical laws, is it possible for individuals to be responsible for their own actions? Or are our lives simply proceeding along preordained paths? Determinism - the doctrine that every event is the inevitable consequence of what goes before - seems to suggest so.Many intellectuals have concluded that free will is logically impossible. The philosopher Baruch Spinoza regarded it as a delusion. Albert Einstein wrote: "Human beings, in their thinking, feeling and acting are not free agents but are as causally bound as the stars in their motion." But in the Enlightenment, philosophers including David Hume found ways in which free will and determinism could be reconciled. Recent scientific developments mean that this debate remains as lively today as it was in the ancient world.With: Simon BlackburnBertrand Russell Professor of Philosophy at the University of CambridgeHelen BeebeeProfessor of Philosophy at the University of BirminghamGalen StrawsonProfessor of Philosophy at the University of ReadingProducer: Thomas Morris.

Melvyn Bragg and his guests discuss the work and influence of Maimonides.Widely regarded as the greatest Jewish philosopher of the medieval period, Maimonides was also a physician and rabbinical authority. Also known as Rambam, his writings include a 14-volume work on Jewish law, the Mishneh Torah, which is still widely used today, and the Guide for the Perplexed, a central work of medieval philosophy. Although undoubtedly a titan of Jewish intellectual history, Maimonides was also profoundly influenced by the Islamic world. He exerted a strong influence on later Islamic philosophy, as well as on thinkers ranging from Thomas Aquinas to Leibniz and Newton.With:John HaldaneProfessor of Philosophy at the University of St AndrewsSarah StroumsaAlice and Jack Ormut Professor of Arabic Studies and currently Rector at the Hebrew University of JerusalemPeter AdamsonProfessor of Ancient and Medieval Philosophy at King's College London.Producer: Thomas Morris.

Melvyn Bragg and his guests discuss Aristotle's Poetics. The Poetics is, as far as we know, the first ever work of literary theory. Written in the 4th century BC, it is the work of a scholar who was also a biologist, and treats literary works with the detached analytical eye of a scientist. Aristotle examines drama and epic poetry, and how they achieve their effects; he analyses tragedy and the ways in which it plays on our emotions. Many of the ideas he articulates, such as catharsis, have remained in our critical vocabulary ever since. The book also contains an impassioned defence of poetry, which had been attacked by other thinkers, including Aristotle's own teacher Plato.Translated by medieval Arab scholars, the Poetics was rediscovered in Europe during the Renaissance and became a playwriting manual for many dramatists of the era. Today it remains a standard text for would-be Hollywood screenwriters.With:Angie HobbsAssociate Professor of Philosophy and Senior Fellow in the Public Understanding of Philosophy at the University of WarwickNick LoweReader in Classical Literature at Royal Holloway, University of LondonStephen HalliwellProfessor of Greek at the University of St AndrewsProducer: Thomas Morris.

Melvyn Bragg and his guests discuss Daoism. An ancient Chinese tradition of philosophy and religious belief, Daoism first appeared more than two thousand years ago. For centuries it was the most popular religion in China; in the West its religious aspects are not as well known as its practices, which include meditation and Feng Shui, and for its most celebrated text, the Daodejing.The central aim in Daoism is to follow the 'Dao', a word which roughly translates as 'The Way'. Daoists believe in following life in its natural flow, what they refer to as an 'effortless action'. This transcendence can be linked to Buddhism, the Indian religion that came to China in the 2nd century BC and influenced Daoism - an exchange which went both ways. Daoism is closely related to, but has also at times conflicted with, the religion of the Chinese Imperial court, Confucianism. The spirit world is of great significance in Daoism, and its hierarchy and power often take precedence over events and people in real life. But how did this ancient and complex religion come to be so influential?With:Tim Barrett Professor of East Asian History at the School of Oriental and African Studies, University of LondonMartin PalmerDirector of the International Consultancy on Religion, Education and CultureHilde De WeerdtFellow and Tutor in Chinese History at Pembroke College, University of Oxford Producer: Natalia Fernandez.

Melvyn Bragg and his guests discuss the history of logic. Logic, the study of reasoning and argument, first became a serious area of study in the 4th century BC through the work of Aristotle. He created a formal logical system, based on a type of argument called a syllogism, which remained in use for over two thousand years. In the nineteenth century the German philosopher and mathematician Gottlob Frege revolutionised logic, turning it into a discipline much like mathematics and capable of dealing with expressing and analysing nuanced arguments. His discoveries influenced the greatest mathematicians and philosophers of the twentieth century and considerably aided the development of the electronic computer. Today logic is a subtle system with applications in fields as diverse as mathematics, philosophy, linguistics and artificial intelligence.With:A.C. GraylingProfessor of Philosophy at Birkbeck, University of LondonPeter MillicanGilbert Ryle Fellow in Philosophy at Hertford College at the University of OxfordRosanna KeefeSenior Lecturer in Philosophy at the University of Sheffield.Producer: Thomas Morris.

Melvyn Bragg and his guests discuss the work of the eighteenth-century philosopher, politician and writer Edmund Burke.Born in Dublin, Burke began his career in London as a journalist and made his name with two works of philosophy before entering Parliament. There he quickly established a reputation as one of the most formidable orators of an age which also included Pitt the Younger.When unrest began in America in the 1760s, Burke was quick to defend the American colonists in their uprising. But it was his response to another revolution which ensured he would be remembered by posterity. In 1790 he published Reflections on the Revolution in France, a work of great literary verve which attacked the revolutionaries and predicted disaster for their project. The book prompted Thomas Paine to write his masterpiece Rights of Man, and Mary Wollstonecraft was among the others to take part in the ensuing pamphlet war. Burke's influence shaped our parliamentary democracy and attitude to Empire, and lingers today.With:Karen O'BrienProfessor of English at the University of WarwickRichard BourkeSenior Lecturer in History at Queen Mary, University of LondonJohn KeaneProfessor of Politics at the University of SydneyProducer: Thomas Morris.

Melvyn Bragg and guests discuss 'The Varieties of Religious Experience' by William James. The American novelist Henry James famously made London his home and himself more English than the English. In contrast, his psychologist brother, William, was deeply immersed in his American heritage. But in 1901, William came to Britain too. He had been invited to deliver a series of prestigious public lectures in Edinburgh. In them, he attempted a daringly original intellectual project. For the first time, here was a close-up examination of religion not as a body of beliefs, but as an intimate personal experience. When the lectures were printed, as 'The Varieties of Religious Experience', they were an instant success.They laid the ground for a whole new area of study - the psychology of religion - and influenced figures from the psychiatrist Carl Jung to the novelist Aldous Huxley. To date, James's book has been reprinted thirty-six times and has been hailed as one of the best non-fiction books of the twentieth century.With:Jonathan ReeFreelance philosopherJohn HaldaneProfessor of Philosophy at the University of St AndrewsGwen Griffith-DicksonEmeritus Professor of Divinity at Gresham College and Director of the Lokahi FoundationProducer: Natasha Emerson.

Melvyn Bragg and guests discuss the life and works of William Hazlitt. Hazlitt is best known for his essays, which ranged in subject matter from Shakespeare, through his first meeting with Samuel Taylor Coleridge, to a boxing match. What is less well-known, however, is that he began his writing life as a philosopher, before deliberately abandoning the field for journalism. Nonetheless, his early reasoning about the power of the imagination to take human beings beyond narrow self-interest, as encapsulated in his 'Essay on the Principles of Human Action', shines through his more popular work.Hazlitt is a figure full of contradictions - a republican who revered Napoleon, and a radical who admired the conservative philosopher Edmund Burke. His reputation suffered terribly from his book 'Liber Amoris', a self-revealing memoir of his infatuation with his landlady's daughter. But in the Victorian and Edwardian eras, his importance was acknowledged by writers like Charles Dickens, Robert Louis Stevenson and Ford Madox Ford. In the 180 years since his death, his stature as perhaps the finest essayist in the language has grown and grown. With:Jonathan BateProfessor of English Literature at the University of Warwick Anthony GraylingProfessor of Philosophy at Birkbeck College, University of LondonUttara NatarajanSenior Lecturer in the Department of English and Comparative Literature at Goldsmiths College, University of LondonProducer: Phil Tinline.