A Dutch philosopher, Eric Hoekstra, recently spent seven days in a wooden barrel. The burly academic from Leeuwarden University occupied a large, upturned tub, placed next door to a bookshop, as part of the Netherlands' celebration of a "national month of philosophy".

Hoekstra (left) spent the days chatting to interested passers-by: "Lots of people visited me, some were shy and just sneaked a look in. Children laughed out loud. Others talked for a while, expressing a more profound interest in what I was doing." The most popular topics of conversation were stress in western society, the modern addiction to luxury, and our habit of repeating pleasures so often that they stop being pleasurable - genotsbevrediging, as the Dutch call this feeling of let-down.