Rana Mitter talks to the eminent primatologist Frans de Waal, who in 2007 was on Time's List of the 100 most influential people in the world. Frans de Waal's groundbreaking book "Our Inner Ape" argued that empathy, morality and the ability to co-operate are inherent in human nature. Such genetically endowed virtues he believes - unlike many economists - drive evolution as much as the darker drives of competitiveness, aggression and selfishness. De Waal believes we should turn to primatologists, not sociologists to understand human behaviour - and argues that understanding the behaviour of other animals holds the key to building a more just human society. To coincide with National Poetry Day this week, a new TV drama starring Emma Thompson and Alan Rickman airs on BBC 2. An adaptation of award winning poet Christopher Reid's narrative book-length poem, The Song of Lunch plays out the drama between two former lovers as they meet in a restaurant that was one of their old haunts, 15 years after the end of their relationship. Rana talks to playwright Neil Bartlett and War Horse puppeteers Adrian Kohler and Basil Jones about their new production at the National Theatre in London. 'Or You Could Kiss Me' is a story of love and the anticipation of loss, as the two central characters, two gay men in their mid-80s - one facing death - look back on the sixty years since they met as teenagers. And as Germany makes its final payment over the Reparations debts from the First World War, Rana is joined by the Historian Richard J Evans and Jurgen Kronig from Die Zeit newspaper to discuss some very old national debt and explain why it took so long.