Episode 1
Bettany begins her journey in the city of Trier on the banks of the Mosel in Germany. It was here on the 5 May 1818 that Karl Marx, one of the most important philosophers of the 20th century was born.
Episode 2
Nietzsche's uncompromising ideas smashed the safe presuppositions and assumptions of religion, morality and science.
Episode 3
Bettany Hughes travels to Vienna on the trail of Sigmund Freud, the father of psychoanalysis.
