The Forum

Indigo: not only one of the seven colours of the rainbow and the dye that makes your jeans look like they do but and a highly valued pigment which is naturally found in some plants and whose use can be traced back at least six thousand years to Peru. Such was the desirability of indigo that along with sugar, cotton, coffee and tobacco it became a major driver for globalised trade and the horrors of slavery. In India it was the source of so much exploitation that a lawyer called Gandhi rose to fame standing up for indigo farmers. Rajan Datar explores the rich history of the dye with Jenny Balfour-Paul, an Honorary Research Fellow at Exeter University and author of Indigo: Egyptian Mummies to Blue Jeans; Lucille Junkere, an artist and textile researcher with a particular interest in the history of indigo in Nigeria and the Caribbean; and Andrea Sella, a professor of chemistry at University College London who delights his students with all kinds of colourful experiments with indigo.Photo: Detail of adire indigo cloth from Nigeria. Credit: Education Images/Universal Images Group via Getty Images

Domesticated cats are thought to have started living alongside humans more than 9000 years ago. Unlike dogs, it's believed cats domesticated themselves, entering the homes of early arable farmers in the Fertile Crescent to control the rodent population. Since then, they've been worshipped, vilified and revered by various societies around the world. Today, they are one of the world's most popular pets, living on every continent except Antarctica and a favourite on the internet, and yet, they will never have that image of loyalty that is associated with dogs.Rajan Datar welcomes three experts in science, culture and archaeology to discuss the history of the domesticated cat: Katharine Rogers - a Professor Emerita of English Literature from City University of New York and author of numerous books including 'Cat' and 'The Cat and the Human Imagination'; Eva-Maria Geigl - an Evolutionary geneticist at the French National Research Institute CNRS; and John Bradshaw - an anthrozoologist from Bristol University, UK, and author of the book 'Cat Sense'.Photo: Copy of wall painting from private tomb 52 of Nakht, Thebes (I, 1, 99-102) cat eating fish, 20th century Credit: Ashmolean Museum/Heritage Images/Getty Images

Manuela Sáenz was an Ecuadorian revolutionary who for many years was most famous for her role as the lover of Simón Bolívar - the Venezuelan military leader who secured independence from Spain for a number of countries in South America between 1819-1830. Sáenz left her British husband for Bolívar, or 'The Liberator' as he was known, and famously saved the leader from an assassination attempt, earning her the name 'Libertadora'. But Sáenz was a political force in her own right, receiving various honours for her work for the revolutionary cause. She continued her involvement in politics right to the end of her life while exiled in Peru, acting as a spy and creating a network of informants.As many countries in what used to be known as 'Gran Colombia' celebrate 200 years of independence from Spain, Bridget Kendall speaks to three experts about Manuela Sáenz's key role in the independence struggle: Pamela Murray, professor of history at the University of Alabama at Birmingham and author of the biography For Glory and Bolívar: The Remarkable Life of Manuela Sáenz; Matthew Brown, professor in Latin American history at the University of Bristol, UK; and Marcela Echeverri, associate professor at Yale University's Department of History in the United States.(Photo: Portrait of Manuela Sáenz in 1825 by Pedro Durante. Credit: Museo Nacional de Arqueología, Antropología e Historia del Perú)

The invention of the electric telegraph in the mid-19th century brought about a revolution in human communication that some argue rivals the printing press and the internet. Suddenly the ‘tyranny of distance’ could be overcome – messages that once might have taken days or even weeks to arrive could be sent almost instantly using Morse code signals. Soon wires reached across continents and under oceans, connecting the world as never before, and radically changing areas such as commerce, diplomacy, journalism and warfare forever.Bridget Kendall discusses the telegraph’s extraordinary impact with Roland Wenzlhuemer, Professor of Modern History at the University of Munich; Bruce J Hunt, Professor of History at the University of Texas; and Gillian Cookson, Historian of Engineering and Research Fellow at the University of Leeds.Photo: Old-fashioned telegraph pole in Rhineland, Germany Credit: bibi57/GettyImages

Made from the simple juice of the poppy, opium is arguably the oldest and most widely used drug in the world. Since prehistoric times it has been used to relieve physical pain and quieten troubled minds. It has enabled medical breakthroughs, and inspired some of the greatest Romantic poets and composers. But opium, and its later derivatives morphine and heroin, has also brought addiction and untold misery and death, destroyed families, and corrupted entire countries. Its trade has provoked wars, and is still making global headlines today, from its production in Afghanistan to the opioid crisis in the United States.Bridget Kendall explores opium’s long and complex history with Doris Buddenberg, former head of United Nations Office on Drugs and Crime in Afghanistan, and curator of a recent exhibition on opium; Zhou Xun, Reader of Modern History at the University of Essex; and Mike Jay, author and cultural historian, whose books on the history of drug use include ‘High Society’.Image: Opium poppy flower Credit: yamatao/Getty Images

‘There is no sun without shadows, and it is essential to know the night,’ the words of Albert Camus, a writer whose exploration of the absurd nature of the human condition made him a literary and intellectual icon. Camus was born in Algeria but is celebrated in France as one of its great twentieth-century novelists and philosophers. His first publishing success, The Stranger, focused on the absurdity of existence but in his later works, including The Plague and The Rebel, he developed his thoughts on the human instinct to revolt. But who was Albert Camus? How far were his ideas shaped by his Algerian upbringing and by the turbulent political times he lived through in the 1940s and '50s? Bridget Kendall explores these questions with three Camus experts: Nabil Boudraa, Algerian professor of French and Francophone Studies at Oregon State University, Eve Morisi, professor of French at Oxford University and Samantha Novello, research fellow in Political Philosophy at Verona University.(Photo: Albert Camus Credit: Kurt Hutton/Getty Images)

Fernando Pessoa is Portugal’s national poet and a giant of 20th Century literature but he’s also a writer who multiplied himself, who wrote under dozens of alter egos, ranging from an engineer trained in Glasgow in Scotland, to a hunchback who is helplessly lovesick, to a doctor and Latin scholar who’s a fervent Royalist. His masterpiece The Book of Disquiet, considered to be one of the defining works of modernist literature, is equally fragmented - written on scraps of paper and consisting of hundreds of virtually unordered manuscripts. So what makes Fernando Pessoa such a great writer and so relevant today? Joining Rajan Datar to discuss Fernando Pessoa and his many selves are his translator and biographer Richard Zenith, and the literary scholars and Pessoa experts Dr Mariana Gray de Castro and professor Bernard McGuirk.(Photo: Statue of Portuguese poet and writer Fernando Pessoa outside Café Brasilera, Lisbon, Portugal. Credit: Anne Khazam/BBC)

Albert Einstein’s inability to get a job on graduating has given hope to generations of students. Knowing what we know now about the genius scientist, it’s hard to avoid smiling on reading his father’s pleas to physics professors to give his son an academic post.Perhaps it was just as well that these attempts failed, as the job Einstein eventually secured gave him the opportunity to daydream. Assessing new inventions at the Swiss capital’s patent office, Einstein allowed his imagination to run riot, creating ‘thought experiments’ that questioned centuries of knowledge about time, space and motion. In 1905 he published a series of papers that scientists today still use as a reference point. While Einstein himself didn’t foresee the technological application of his work, his research has since been used as the basis of modern inventions such as the atomic bomb, lasers, solar panels and GPS. Neither did he realise immediately the potential of his theories to help us understand the beginning of the universe.Rajan Datar explores the complexity of Einstein’s theories as well as what made him tick, with expert guests Janna Levin, professor of physics and astronomy at Barnard College, Columbia University, USA; science historian Jimena Canales, author of The Physicist and the Philosopher: Einstein, Bergson and the Debate that changed our understanding of Time; and Matthew Stanley, professor of the history of science at New York University whose book Einstein’s War: How Relativity Conquered Nationalism and Shook the World was published in 2019.(Image: Portrait of German-born physicist Albert Einstein on his 75th birthday. Photo by American Stock/Getty Images)

Fans of Hollywood cinema may recognise the name Imhotep from the original The Mummy film from 1932, and its various remakes. In the movie, Imhotep (played by Boris Karloff) is an Ancient Egyptian high priest who was mummified alive because he had attempted to resurrect his forbidden lover. Fast forward several thousand years, and an archaeologist brings the mummy back to life, with dangerous consequences.The real Imhotep was a far cry from this Hollywood invention. A high priest yes, but also possibly the architect of the first monumental building fashioned entirely of stone, the Step Pyramid which dates from around 2,600 BC. Imhotep was also an adviser to one of the most important pharaohs, King Djoser, as text on a statue base found at the Step Pyramid confirms. Later generations revered Imhotep as a sage and a scribe, one of the highest honours a person could be paid in Ancient Egypt. He eventually became linked with the Greek god of medicine, Asclepius, and then worshipped as a saint. Bridget Kendall journeys through the centuries to understand all the different titles that have attached themselves to this legendary figure, with experts Dr David P Silverman, curator in charge of the Egyptian Section of the Penn Museum and Professor of Egyptology at the University of Pennsylvania, USA; Dr Salima Ikram, Distinguished Professor of Egyptology at The American University in Cairo, Egypt, and Dr Aidan Dodson, Honorary Professor of Egyptology at the University of Bristol in the UK.(Image: Step pyramid of King Djoser, Saqqara, Egypt Credit: Print Collector/Contributor/Getty Images)

"In the future everybody will be world-famous for fifteen minutes” is probably the best known quote attributed to Andy Warhol. Warhol was an American artist who became a superstar in the visual art movement known as Pop Art. He crossed the boundaries between art and celebrity becoming famous for what we now call branding, but the private Warhol was a deeply religious man and to his close relatives was known simply as ‘Uncle Andy’. In a world where some of what he predicted has come true, we look back at the life and work of this iconic figure.With Bridget Kendall to explore Andy Warhol are Eric Shiner the former Director of the Andy Warhol Museum in Pittsburgh USA and New York Director of London’s White Cube, Professor Jean Wainwright the British art historian and curator and a leading expert on Warhol and Andy Warhol’s nephew, the artist and illustrator James Warhola.(Photo: Andy Warhol. Credit: Ullstein Bild/Getty Images)