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What triggers earthquakes and why do we know so little? Plus the Arctic and African cities
BBC World Service Online
Prominent international thinkers debating big ideas.
What gives an object meaning and value? The Forum this week comes from the British Museum.
To see the world differently, opt out of society or just watch water boil!
Why a vast array of unknown species is still out there waiting to be discovered
We challenge assumptions about Australian heroes, history and humanity