Melvyn Bragg examines 20th century physics’ quest for the ultimate theory of everything. Einstein left us with his theory of General Relativity, which explained how gravity works on the scale of stars, galaxies, and the universe itself and Schroedinger left us with the equation that explained the mechanics of the tiny quantum realm. Both theories work to wonderful effect in their own worlds, but (and this is the sticking point) gravity is strangely absent from the quantum realm and planets behave nothing like particles. The enigma for scientists throughout most of the last century is that, as they are currently formulated, general relativity and quantum mechanics cannot both be right. The history of twentieth century physics has been a struggle to find a way to unite them, to find what has become the holy grail of modern physics: The Grand Unified Theory. With Brian Greene, Professor of Physics and Mathematics, Columbia University and Cornell University; Sir Martin Rees, Astronomer Royal and Royal Society Research Professor in Astronomy and Physics at Cambridge University.

Explore Goethe's contributions to geology, botany, and anatomy, his transition from poet to scientist, and his critique of Newton's color theory. Discover his belief in replicable experiments and collaboration for scientific progress.

Melvyn Bragg discusses the social and economic consequences of the information revolution. There are now more than 200 million people connected to the internet world-wide. The world’s biggest ever merger has just seen Time Warner united with the internet service provider America Online, and in the United States alone it is predicted that transactions conducted in cyberspace will account for 327 billion dollars worth of business by 2002. Should we be pleased? Is it the ‘third wave’ as Dr Toffler predicted in 1980 - after the first wave, the agricultural revolution about 8000 BC and then the second, the Industrial Revolution three centuries ago.Is this change going to alter our society radically, empowering the individual and offering greater choice, or will information technology lead us into a dark age for society that destroys democracy, the work-place and family life? With Charles Leadbeater, Demos Research Associate and author of Living On Thin Air: The New Economy; Ian Angell, Professor of Information Systems, London School of Economics and author of The New Barbarian Manifesto: How to Survive the Information Age.

Melvyn Bragg discusses climate change. In 1999 the weather gave the planet’s occupants a terrible beating: 16,000 people lost their lives as a result of storms. Some 15 million people were left homeless and 10,000 died when the world’s worst cyclone swept across eastern India. Hurricane Floyd wreaked 4.3 billion pounds worth of damage in the United States, Typhoon Bart hit Japan and Typhoon York hit Hong Kong and Macau. Western Europe is unused to hurricane force winds, but since Christmas 80 people have died in France as a result of storms. And in Venezuela floods and mud slides are continuing to cause devastation on a massive scale.The climate has become political but is the science, supposedly underpinning apocalyptic and apposite millennial claims of doom, really water-tight? It might seem that the effects of global warming are already upon us, but are they - and if so how can we really hope to stop them? With Sir John Houghton, Co-Chair of the Inter-Governmental Panel on Climate Change - the United Nations’ global warming science committee; George Monbiot, environmentalist, journalist and Visiting Professor, Department of Philosophy, Bristol University.

Melvyn Bragg and guests discuss the history of mankind’s attempt to understand the nature of time. At the end of the 19th century, H.G.Wells imagined travelling through time in The Time Machine; “The palpitation of night and day merged into one continuous greyness; the sky took on a wonderful deepness of blue, a splendid luminous colour like that of early twilight; the jerking sun became a streak of fire, a brilliant arch in space”. When he was writing we thought time was unbending and universal and counted out by Newton’s clock. A hundred years later we have had Einstein and relativity, quantum theory, and atomic clocks, but in the third millennium, is mankind any closer to understanding what time really is? What, in short, do we know about time itself? A Greek philosopher thought that time was a figment of the imagination and there are contemporary physicists who go a long way to agreeing with him. Newton’s views on time were bent by Einstein. The ancient skills of astronomy once ruled the known world and skill in time usage could be said to be enthroned as a master craft in our day. “But at my back I always hear time’s winged chariot hurrying near and yonder all before us lie deserts of vast eternity” - Marvel wrote that of love, but it could be our epigraph for time. With Dr Neil Johnson, theoretical physicist at the Clarendon Laboratory, Oxford University and Royal Institution Christmas Lecturer 1999 on the subject of Time; Lee Smolin, cosmologist and Professor of Physics, Pennsylvania State University.

Melvyn Bragg examines the technological advances and ethics of modern medicine. On an average working day about three quarters of a million of us go to the doctor’s. About a hundred thousand are visited by nurses and other health professionals. Then there are the three hundred thousand that go to the dentist. Health is a central preoccupation. It is also big business, saving life, lengthening life and even promising a stab at eternal life. Yet while some technology is Space Age, the morality is often not far away from the Stone Age. Who decides who lives or dies? Insurance firms, for instance, want genetic information - should they have it? Stem cell research - hailed by many as an extraordinary advance - now runs into conflict with those who do not want the human embryo to be, as they see it, abused. In the 16th century Francis Bacon told us in his Advancement of Learning “Medicine is a science which hath been more professed than laboured, and yet more laboured than advanced: the labour having been, in my judgement, rather in a circle than in a progression”. Well, after a century that has brought us penicillin, the discovery of DNA, heart transplants and key-hole surgery, have we finally escaped the loop? Or does our ethical application of what we can technologically achieve mean we are marching in Bacon’s circle still? With Barry Jackson, consultant surgeon and President of the Royal College of Surgeons of England; Professor Sheila McLean, Director of the Institute of Law and Ethics in Medicine, Glasgow University.

Melvyn Bragg and guests discuss the problems of consciousness, one of the greatest mysteries facing science and philosophy today. The frustrations, the stubborn facts and the curiosities of today’s thinkers, philosophers, physicists and psychologists, demonstrate the elusiveness, and the utter impenetrability of consciousness. Can we explain our perception of colour, smell or what it is like to be in love in purely physical terms? Can memory, conviction and reason be explained primarily in terms of neural firing sequences in the brain? Three centuries ago Descartes famously believed that the problem was best solved by being ignored. Was he right? Could it be that the human mind is just not built to understand its own basis?With Ted Honderich, philosopher and former Grote Professor of the Philosophy of Mind and Logic, University College, London; Sir Roger Penrose eminent physicist, mathematician and author of The Large, The Small, and the Human Mind.

Melvyn Bragg and guests discuss the theory of Genetic Determinism. In the middle of the last century two men - Gregor Mendel, an Austrian monk, and Charles Darwin, an English naturalist, established the central theories of modern biology and changed the world forever. Darwin’s On the Origin of Species has been described as the book of the Millennium, “the only best-seller to change man’s conception of himself”. Through the rediscovery of Mendel’s work in the early decades of our century, evolutionary theory was transformed by the emergence of genetics as a science. Crick and Watson found DNA at Cambridge and announced that they had discovered the secret of life in a local pub, and the rest has been the most compulsive element in the intellectual history of the twentieth century. It seems as if almost every week we read about another gene which claims to determine our fate - whether it governs our intelligence, personality or sexual orientation. Many rail against what they see as “genetic determinism” - the idea that genes are the destiny we can do nothing about. Others willingly blame their anti-social behaviour on “criminal genes” - thus absolving themselves of any responsibility. Genetics may be all about inheritance but is inheritance all about the genes? With Steve Jones, Professor of Genetics, University College, London and author of Almost Like a Whale: The Origin of Species Updated; Matt Ridley, science journalist, chairman of the International Centre for Life and author of Genome: The autobiography of a species in 23 chapters.

Melvyn Bragg and guests discuss pain; something of which everyone has an individual experience. What causes it, how do we cope with it, what mechanisms are involved, what is the traditional view of pain and how is that being challenged today? Do we experience pain in the same way and how is emotional pain different from physical pain? What can our experience of pain tell us about ourselves and human consciousness? Is each individual human experience unique or are there experiences we can say apply across all of human consciousness? Is science a blunt instrument for examining subjective experience?With Patrick Wall, Professor of Physiology at St Thomas’ Hospital, London and author of Pain: The Science of Suffering; Semir Zeki, Professor of Neurobiology at University College, London.

Melvyn Bragg and guests discuss a question that has stalked the twentieth century: Intelligence. Since the first IQ tests were invented in 1905, the question of what makes Homo Sapiens stupid and what makes him clever has involved human kind in sterilisation, racism and misery. How do we define intelligence, how do we measure it; what are its origins and how do we uncover it? But are we any closer to understanding what this elusive quality of intelligence is? The debate still rages as to whether we are born with it or whether intelligence is something we develop as we grow, and evidence for either camp seems to pile up almost daily. With Dr Ken Richardson, educational psychologist, former Senior Lecturer, Open University and author of The Making of Intelligence; Professor Michael Ruse Philosopher of Biology, University of Guelph, Ontario and author of Mystery of Mysteries: Is Evolution a Social Construction?