Cities and Walking

Walking hints at a hidden connection between the physical world and the realm of thought. As the sights of the city unfold before our eyes, so do our problems unravel and our ideas compound. Familiar places unearth forgotten facts; each unexplored alley promises an epiphany. It should come as no surprise then that many of the great thinkers were also great walkers, a connection that probably goes back even further than Aristotle's peripatetic lectures. Kant's daily walks were so regular that clocks were set by them. Kahneman and Tversky used to walk together as they thought through the problems in behavioural economics which would lead to a Nobel prize. Nassim Taleb likes holding discussions while walking, but only if his partner walks slowly enough. It is heartening to see I follow in distinguished footsteps with my habits. When I was little, I used to pace my room as I roamed elaborate fantasy worlds. Now I ponder my philosophical projects as I walk, whether on my way somewhere or wandering without destination. It is surely an oversight of the English language that there is no word for the combination of walking and thinking.

There are the obvious physiological benefits of walking for thought. A comfortable stroll increases blood circulation to the brain without being too taxing on heart or muscle. The tempo of our steps seems to nudge our thoughts onward. Physical activity maintains our state of arousal, lest our thoughts lure us to sleep. Sensory engagement with the surroundings stimulates the hippocampus, improving memory consolidation.

The pseudo-random stimuli may also act as noise to amplify the signal of ideas too hazily formed to be grasped on their own. Moving into a different locale may serve as a marker for switching to a different approach to thought, guiding cognitive search between local and global levels. Of course, a thought-provoking word in a sign or a serendipitous item in a shop window can serve as the trigger to a solution, like the apocryphal apple of Newton and the oneiric ouroboros of Kekulé.

What features of a city make it amenable to thought, if not appealing to flâneurs? It must have sufficient walkability, as a sine qua non. The walkways must be wide and the crowds not too dense to reduce resistance and turbulence. The paths should be dendritic, with just enough lanes and alleys to suggest adventure without leading to a paralysing embarras du choix or becoming a disorienting labyrinth. And of course there must be enough of interest in the city. These can come in the form of avenues and arcades, bridges and canals, monuments and sculptures, shops and cafés, buskers and peddlers, and many more. It is important that the city has a style of its own. Calvino's Marco Polo said, "You take delight not in a city's seven or seventy wonders, but in the answer it gives to a question of yours." A city without wonders is not likely to answer any questions, but raise a few of its own.

How then shall we go about building a city that answers questions for everyone, like a Quora of brick and stone? Perhaps by reversing the process we desire and melding thought and concrete in the first place. If passers-by can use their smartphones or Google Glasses or some other devices to add comments, suggestions, questions, or even random thoughts to a particular location in the city, like cyber-graffiti, then the city will be overlaid with thought, and soon develop a symbiosis, as suggestions become physically instantiated and new places and happenings in the city generate further ideas. This way, we harness the wisdom of crowds, while also accelerating the organic bottom-up growth of the city for its people, by its people.

The discourse will be not merely architectural and urban, but also sociological and political. Each answer the city gives us will also be a prompt to ask another question. The very way we live will be transformed. The invisible city in which we live will become more visible, yet each time the visible part is extended so is the invisible part. Such adapting cities would also evolve memetically as city plans are informed by each other, like actual genetic algorithms. Would all happy cities be alike, or would we see an explosion of diversity, where tiny differences in histories are amplified to radically distinct destinies? There is only one way to find out. The flâneurs have nothing to lose but their footprints. They have cities to win. Flâneurs of the world, unite!