The evolution of cities: Geddes, Abercrombie and the new physicalism

Michael Batty is Bartlett Professor of Planning, Centre for Advanced Spatial Analysis, University College London, 1–19 Torrington Place, London WC1E 7HB; email: [email protected]. Stephen Marshall is a Senior Lecturer in Planning, Bartlet School of Planning, University College London, 22 Gordon Street, London WC1H 0BJ; email: [email protected] One hundred years ago, the first coordinated reactions to the urban chaos of the industrial revolution were being established though a system of centralised planning, while the rudiments of a theory underpinning this collective action were also being fashioned, through the writings and rhetoric of Patrick Geddes. Drawing on Darwin’s theory of natural selection, he laid the foundations for a response to urban growth that drew loosely on ideas of evolution, but which ultimately became established through the imposition of a top-down ‘organic’ order in city and regional plans associated with the work of Patrick Abercrombie, one of Geddes’ best-known followers. This approach was rooted in ‘physicalism’, a perspective that assumed social problems might be solved by manipulating the physical built environment. This ideology began to fragment from the mid-twentieth century on as questions over its effectiveness in generating more liveable and equitable urban environments grew. Now, however, there are signs that with the contemporary problems of climate change, energy and sustainability, this viewpoint is being reasserted. We argue that the seeds of this perspective were first developed 100 years or more ago, primarily by Patrick Geddes, but that his unique style diverted the field from grasping the real message of an evolutionary physicalism, which is only now becoming apparent.