The concept of 'space' is fluid, contingent upon the circumstances of the moment. Sociologists have demonstrated how ideas of place can arise, change, even disappear in the age of the Internet and the fast jet engine. They have also shown how the concept of space can be used to analyse problems as diverse as normative ideas, pathological fears, and professional and political power. 1 In that last vein, David Harvey argued in 1973 that 'created space […] reflects the prevailing ideology of the ruling groups [… it] is an integral part of an intricate sign-process that gives direction and meaning to daily life'. 2 Harvey's insight came at the high-point of Marxism's influence in the social sciences. But it also gave expression to a remarkable collapse in confidence in the objectivity of governments at a time when even the most optimistic writers accept that 'Britain seemed to be in a state of collapse'. 3 This was a remarkable descent from the optimism of the post-war world. As Minister of Health Aneurin Bevan declared, when he laid the foundation stone of the Spa Green Estate in Finsbury in July 1946: 'we are going to […] rebuild Britain […] with cities that will be the joy of generations to come'. 4 How and why had this great sea-change occurred?This ideology of the social democratic era had clearly identifiable characteristics, and Alison Ravetz has delineated six main elements. First, they were supposed to be scientific, based in the method of 'survey then plan'; partly because of this, second, they were thought of as universal and comprehensive, giving expression to set rules about urban life; third, they were positivistic, aiming to change human behaviour by changing the environment. Fourth, they would be an ongoing process, continually reacting to dynamic change; fifth, they would segregate land use in an orderly manner. Sixth and last, architects and planners hoped to organise housing in small to medium-sized neighbourhoods that would foster social and community life. 5 The claim to be rational, scientific and modernising brought together at least five of Ravetz's six themes, as it was scientific, comprehensive, positivistic, dynamic and orderly.