An architect devises a style of building in which it is impossible to be bad. Something about the architecture puts the brain into a state of happy fellow feeling, encouraging moral behaviour. This style of architecture is immediately adopted for all public buildings. Gradually public life becomes increasing safe but also increasingly bland and featureless. A group of activists discover that just introducing unexpected elements – statues, trees, playground equipment – can jam this effect. The very success of their campaign, the fact that they're able to carry out these interventions within the 'good' buildings means that what they're doing is also somehow 'good'. It is good not to be wholly good all the time.