Historian Bettany Hughes retraces the lives of three great thinkers whose ideas shaped the modern world - Karl Marx, Frederick Nietzsche and Sigmund Freud.

Marx's masterpiece Das Capital was largely overlooked in his lifetime, and only 11 people attended his funeral. Yet his ideas would generate one of the most influential, and divisive, ideologies in history. Drawing on expert opinion and new evidence, Bettany reveals the flesh-and-blood man and his groundbreaking ideas

The philosopher Friedrich Nietzsche was one of the most brilliant and dangerous minds of the 19th century. His uncompromising and often brutal ideas smashed the comfortable presuppositions and assumptions of religion, morality and science.

The sixth of Michael Sandel's famous lectures on the philosophy of justice looks at the Greek philosopher Aristotle and the rules of golf.