HARDtalk speaks to the designer of one of London's newest and most controversial buildings - Renzo Piano. He is one of the world's most accomplished and feted architects; and one used to dividing opinion. Back in the 1970s he designed Paris' Pompidou Centre and since then has taken on high profile developments all over the globe. His latest creation - The Shard, which is currently the EU's tallest building - is already loved, but it is also loathed. What does the Shard say about us? And why build it so big?