– Viv Straw

Unlike philosophers of science, planners cannot point to a single philosophical idea that drives their decision-making processes. Science and its resultant technological outputs are founded on a theoretical paradigm.

The Universe is made up of materials and energy sources that act, perhaps react,  in predictable ways. This fundamental constant allows scientists to study the phenomena to find the patterns and eventually design new technologies to take advantage of research findings. For science to be successful, it is necessary to be able to repeat the test and get the same result: this is evidence based science.

The philosophy of science is as much about process as it is about how things work. Scientists create an idea about how something might work (a hypothesis) and then work out how to test it. After running some tests, they check against their original hypothesis and report on whether or not the theory was accurate or if it needs changing.


Science in its fundamental form says that we can think of how something works (hypothesis), test it out (experiment) and compare the results with hypothesis. This process is sometimes referred to as a positivist approach in that it is only applicable to things that can be measured, and these measurable things constitute reality.

Once scientists have sorted out how something works, they can apply the new knowledge to new technologies.

Planning is not positivist or realist approach but ideological: Imagining other ways of doing things or of relating to each other. Planning practice tends to try to establish new worlds based on an idea that may never have been tested using fundamental thinking processes. Many now argue for evidence-based planning. But there is a question about what evidence planners are seeking. How can things in a social context be tested? Would the circumstances be repeatable?

San Diego

Past practice has always been the application of a social idea. New garden cities projects tried to rethink the polluted, overcrowded, unhealthy, vermin, and crime ridden cities of two centuries ago. But this philosophy, as pointed out by its critics, began by blaming the city for the issues. The issues were elsewhere, poverty, joblessness and a lack of environmental knowledge, coupled with a lack of understanding of urban issues drove poor outcomes in crowded places. The planners of two centuries ago saw the poverty and assumed that a changed environment would change lives and people. A utopianism that believed that people need a place in a garden town that could provide open space, a place to grow vegetables and to get exercise and refreshment. This new location would have a spiritual renewing process that would rekindle the lost human spirit and build healthy minds, bodies and spirits. Returning people to the Garden of Eden was the solution to the broken humanity that they witnessed. And slum clearance programs of various sorts continued to be the solution in many minds for a long time.

Two centuries later the world is again moving back into the city. The movement is most noticeable in developing places, while post-industrial, industrialised and new knowledge economies are much more stable having reached greater than 80% urbanisation. But the cities of our developing nations are still growing, and rural populations are looking to them for work and starting new lives.

The New Urbanism of the 1980s reacted with numeric codes to make places more functional and to deliver walkability and neighbourhood relationships. Now the experiment is about mixed use granularity and the ‘live where you live’ mantra of developing employment, recreation, consumerism and residential development in cohabitation. Sometimes referred to as the first, second and third place arrangements, this is an urban experiment with no precedent.

So, what philosophy drives this? Is it just a bewildering array of untested ideas. In the background, there are scientific studies that seem to have identified why the trends are happening. Richard Florida in his work distinguishes some drivers of the creative class as he refers to it. Industrial cities that have seen a resurgence moved up to higher value development or attracted new industries but do not seem to have moved from industrial to knowledge economies. Instead, they have added value to what they do. They have reinvented their infrastructure and repurposed buildings, to create new places with new meanings.

What is the philosophical base that drives this? How can it be evidence based? Can it?  The issues are multi-layered and multi-faceted in a changing context. And unlike the New Urbanist approach planning in this respect is not looking for numeric solutions to relationship problems. And that is what they are. The problem is that we need to identify how we relate to each other in society, how people relate to the urban environment and the natural environment.