There is a view that historic cities have all the answers and we just need to look at them. Or, in any case, it’s just common sense. If professionals had a bit more common sense they would make a better set of decisions.
There are at least three reasons why this can’t be entirely the case. Or, if it is, why our definition of common sense needs careful construction.
First, the variety of different forms of urbanism – of scale, of climate, of culture to name but three – is so great that there is too much common sense to learn. The heterogeneity of reality is beyond any kind of professional common sense. What is needed is not common sense but local knowledge, scaled up into knowledge sets, analysed and synthesized into theory and, finally, externalised into methodologies and technologies to guide practice. A particular, place-specific sense.
Second, the scale and pace of urban change is now so great that new forms of urbanism are being created for which there can be no prevailing common sense. Cities are growing larger, with increasingly large areas of unplanned and informal neighbourhoods. The car is creating new forms of non-traditional urbanism, and not always to the detriment of places. Technology is replacing some kinds of human interaction and enhancing others. These new kinds of urbanism require careful analysis and new thinking. A new thinking to cature the uncommon senses that are emerging.
Third, common sense is so often tied in with local knowledge. There is a belief that, if only you ask local people, common sense will prevail and all the answers will emerge. Of course it is right that local knowledge is tapped. But so is it also right that this local knowledge is brought together with an appreciation of the big picture that local, common sense can often not include. Places work at a local scale not only because of how they a designed locally but also how they are configured at the larger scale. The schism of scales, between architectural urban design operating at the local level and urban planning at the global, is detrimental to the sustainability of places. Individual knowledge at the local scale needs bringing together with analytic understanding at the global to create a common sense across scales.