I was bouncing around London yesterday, on one leg, by taxi, i got into a conversation about ‘The Knowledge‘. To be a cabbie in London, you have to acquire The Knowledge, a notoriously difficult task, typically taking three or four years, studying up to thirty hours a week. The Knowledge is, to put it simply, a mental map of London, the ability to take a destination from a customer and to know the quickest route, and various other routes should there be heavy traffic or delays. To have The Knowledge is to know the city inside out, and backwards.
You start with the ‘Blue Book‘, listing three hundred and twenty routes, and quite literally ‘get on your bike‘, learning the roads, starting to build a foundation mental schema. These routes are called ‘Runs‘, just a starting point in creating a framework understanding of the topography. Once this map is embedded, you learn ‘Points‘, landmarks, restaurants, hotels, pubs, offices and so on. Points are scattered around the runs, enhancing your mental representation of London.
Next come ‘Turnarounds‘, these are junctions, literally special routes to reorientate yourself in a different direction: for example if you are heading down Oxford Street, east to west, it’s actually hard to turn off, not many exists, lots of one way streets, so you need to know how to reorientate yourself north to south anywhere on the map. These are short cuts, cut throughs, expertise learnt over the years and codified as part of this vast tribal knowledge.
Once you’ve mastered all of this, you turn up at the examining office for your ‘First Appearance‘, when the examiner gets you to narrate any number of journeys around town. Assuming you pass, you go back, every fifty six days to do the same again, harder each time. When you get good enough, it drops to every twenty eight days, then finally to every twenty one days. At this point, you will either pass or fail, and when a badge comes up, you will be eligible to buy it and become a cabbie.
So what’s happening over this time? How is this knowledge changing you? It’s been well documented that learning The Knowledge physically changes the brain, where the posterior hippocampus is enlarged. This part of the brain that deals with route finding and our mental maps. The learning actually rewires the brain, which appears to maintain a high degree of plasticity into adult life (although this seems to come at a cost: adapting to be superb at navigating in London appears to make you ‘worse’ at learning to navigate in other cities, the theory being that this part of the brain is, literally, filled up, or specialised for London.
It’s amazing how adaptable the brain is, how we are able to learn new skills, how we can adapt, even more amazing that sometimes these changes are so significant that they can literally be seen in the physiology, although i guess it’s not different from seeing the finely sculpted physique of an athlete or dancer, each specialised in their own way.
I was fascinated by the structured approach to teaching what must originally have been verbal tribal knowledge, passed from one driver to the next or built up purely through necessity. Slowly this was codified into The Knowledge’: multiple narratives captured into the Blue Book, then the archaic structure of presenting yourself and, finally, being accepted. It’s a latter day company of knights of the road, a round table with a steep learning curve to get a place.
In the days of sat nav and gps, it’s strangely archaic, as we see in many other cities where drivers just punch it in and follow directions. I guess that, longer term, there is no possibility of the knowledge surviving, it’s really just an elaborate protection measure to stop just anybody becoming a cabbie. So the evolution of the specialist brain around this type of navigation will die out, just as, in the past, we would have seen people specialising in various other skills that have become redundant, superseded by new technology, extinct.
And this isn’t just a historic oddity, it’s significant if we look at preserving software languages or early computers: the specialisms that created them are changing faster than ever. Our ability to learn is amazing, our ability to forget no less so.
We are adaptable creatures, but sometimes knowing what knowledge to hang onto and what can safely be lost is a challenge.