The Knowledge
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Chatting with my London cabbie on a longish ride, I was intrigued by how he frequently referred to "the Knowledge". He did so respectfully and reverently, as though it were a sacred catechism he had mastered after years of diligent study. Even though he was speaking, it always sounded as though it came with a capital letter at the beginning. And rightly so, because it is holy writ for London cabbies.
"Learn the Knowledge of London"
London's taxi service is the best in the world, in part because our cab drivers know the quickest routes through London's complicated road network. There are thousands of streets and landmarks within a 6 mile radius of Charing Cross. Anyone who wants to drive an iconic London cab must memorize them all: the Knowledge of London.
The Knowledge was introduced as a requirement for taxi drivers in 1865.
Mastering the Knowledge typically takes students three to four years; it's a challenge, but plenty of help and support is available if you are determined.
I've been to London many times, but have never failed to be impressed by the professionalism and courtesy of the cab drivers and the quirkiness of their black taxis (aka "hackney carriages").
The linguistic reason for this post is not only for the idiosyncratic usage of the word "knowledge" that it describes, but because it fits in with the theme of what knowledge is that we have been exploring in recent posts on AI.
Selected readings
Tim Leonard said,
December 6, 2024 @ 11:45 pm
There's a BBC 4 documentary about it. https://www.youtube.com/watch?v=HEEe6U3dfZ8
There was a 1979 comedy/drama film about it. https://en.wikipedia.org/wiki/The_Knowledge_(film)
There's a Tom Scott episode about it. https://www.youtube.com/watch?v=ZmWREtcDVBE
And I'm sure much more. I think I remember reading that there's a measurable change in brain shape as the Knowledge is acquired.
Martin Schwartz said,
December 6, 2024 @ 11:50 pm
My father was a cabby and trucker in New York City.
I once accompanied him on his delivery route, and was awed
by his streetly and social savvy. He would have related positively
to his London confrères' "the Knowledge" in fact, he could have been a Londoner, since his Bessarabian parents had children in London and Wales before coming to Canada, where he was born.
Martin Schwartz
Seth said,
December 7, 2024 @ 5:10 am
But this isn't something which needs "AI" to be computerized. It's essentially memorizing a large complicated graph with a big table of the shortest route between any two nodes. It's of course impressive to do it at the human level. However, it's very much a data and algorithm process. This is akin to the job of doing manual calculations in the era before modern computers.
There's a profound sociological issue here also, in that having to this memorization to get the driver job, is arguably no longer of value in the era of GPS and pocket supercomputers.
Philip Taylor said,
December 7, 2024 @ 5:27 am
There are, very sadly, also a few London taxi[meter cabriolet] drivers who take advantage of "the Knowledge" to take an unwittings fare a longer (and therefore more remunerative) route than required. On the sole occasion on which this happened to me (I knew the optimal route very well), I challenged the driver, who responded (although not using the actual words) with the time-honoured "it's a fare cop, Guv. !" [pun intended].
Victor Mair said,
December 7, 2024 @ 6:58 am
My cabbie said that the only time GPS comes in handy for him is when it informs him of unusually heavy traffic due to an accident, road work, a special event, etc. In fact, before we set out, he told me that the trip would take so many minutes because of the day of the week and the time of day, which would be longer than at other days and times.
Victor Mair said,
December 7, 2024 @ 7:19 am
Speaking of the presence of East Asian speakers and the transmission of their culture to Britain, together with their introduction to black cabs, see here (especially the second photograph).
Coby said,
December 7, 2024 @ 9:21 am
I'll take a double-decker bus over a black cab any bloody day.
mkvf said,
December 7, 2024 @ 9:49 am
It apparently measurably reshapes their brains:
https://www.nature.com/articles/nature.2011.9602
On Seth's points, there are other benefits to black cabs over GPS-enabled platforms. You wave your arm, the cab stops, you tell them vaguely where you want to go, and they know the best way there. You're not reliant on knowing the exact address or postcode. I guess that's vaguely language related too, in that it shows how flexible human-to-human conversation is, compared to human-to-machine.
In non-language related benefits, they have to stop when their light is on, and they have to take you wherever you ask. That has had an effect on British English. Barristers here work to the 'taxi cab rule'. They can't pick between cases based on what the client is accused of or how complicated the case will be.
DJL said,
December 7, 2024 @ 10:46 am
The Knowledge only really covers central London; ask to go anywhere outside central London, and I'm sure most black cabs will be using a satnav – I live in South East London, and that has definitely been my experience. In any case, apart from cases in which one is carrying a lot of luggage or it is the middle of the night (or there's a strike), I don't understand why anyone takes black cabs in central London…(buses and the tube for me, and if not, then it is ubers, especially outside central London).
And yes, The Knowledge has nothing to do with large language models.
Stephen Goranson said,
December 7, 2024 @ 12:45 pm
A different "The Knowledge" has been offered by some gurus, and jnana marga, and gnostics.
GeorgeW said,
December 7, 2024 @ 3:54 pm
It is impressive, but so was my Uber drive the other night in Tampa with a driver who spoke no English and had clealy been in this country for a short time. (He was using their app which gave directions in Spanish)
I wonder if this is the last generation of 'The Knowledge' drivers.
David Morris said,
December 8, 2024 @ 5:03 am
Mightn't all experienced drivers in major, non-grid cities have the same knowledge?
By way of counter-example, in Dec 2022 my wife and I flew from Sydney to Seoul-Incheon, then took a airport bus to Seoul-Gimpo and a taxi to her brother and sister-in-law's house in a back-street of a minor suburb of a major suburb. The driver tapped the address into his GPS, then drove along one major road, turned onto another major road, then a side street then a back street, deposited us somewhere we didn't recognise at 11 pm and sped off. After some exploring we discovered that we were one block parallel to where we wanted to be. Dropping us one block the other way would have been less of a problem because it contained a local mini-mart and was towards the local main road. He brother and sister-in-law couldn't help because he was working in another country and she was visiting him.
Stephen said,
December 8, 2024 @ 6:29 pm
@DJL
"The Knowledge only really covers central London"
IIRC it is a circle of 6 mile radius centred on Charing Cross. That covers quite a bit of area, even some that is 'Sarf of the river'.
I have got a black cab home a few times ("the middle of the night" or at least after public transport had effectively shut down) and when I said where I wanted to go the cabbie has said that the Knowledge only goes as far as Catford. I have responded that I can direct him from there and it is easy to get back to Catford from the destination and that has been sufficient.
"ask to go anywhere outside central London, and I'm sure most black cabs will be using a satnav" maybe now, it is years since I have used one.
Chris Button said,
December 9, 2024 @ 9:43 am
I'm surprised no-one has mentioned issues with GPS/Satnav in major cities. Whenever I drive into NYC, my GPS seems to get confused. I assume it is due to all the conflicting signals bouncing around. At least, it's a city that is easy to navigate.
John Swindle said,
December 9, 2024 @ 11:38 pm
The eponymous mystery novel by the American writer Martha Grimes is delightful. In the book, The Knowledge is both the London cab drivers' professional qualification and the name of a certain pub which only they can find.
DJL said,
December 10, 2024 @ 3:22 am
@Stephen Catford is not a bad outer ring boundary, as it were, but house prices as they are, I think Bromley is becoming the new centre of SE London, which is where I live.
Philip Taylor said,
December 10, 2024 @ 4:42 am
But have you lived there sufficiently long to remember the incredible smell of roasting coffee emerging from Importers Ltd and filling the whole High Street, DJL ?!
Pedro said,
December 10, 2024 @ 5:54 am
There is in fact a wonderful science fiction novel about a future society based on the ancient wisdom of a London cabbie. Sections of the Knowledge are recited as litany, despite the fact that the streets being named have long been submerged after an apocalyptic flood. It's called The Book of Dave by Will Self.
DJL said,
December 10, 2024 @ 3:16 pm
@Philip Taylor you mean Bromley High Street? I don't think there's any roasters there (been in the area since 2017, but I live closer to Beckenham)
Stephen said,
December 10, 2024 @ 6:51 pm
@DJL
"Catford is not a bad outer ring boundary"
I didn't say it is. You said that the Knowledge only covers central London, and I don't think you would find many people that regard Catford as central London.
@Philip Taylor
"the incredible smell of roasting coffee emerging from Importers Ltd and filling the whole High Street"
DJL is correct about there being no roasters on the High Street – we live walking distance from it. And Importers is long gone – we moved here in 2007.
However it did come up in conversation with someone who is a much longer Bromley resident. That was months ago so I don't remember anything other than a comment about the smell.
Andrew Usher said,
December 10, 2024 @ 7:56 pm
John Swindle wrote:
> The eponymous mystery novel by the American writer Martha Grimes is delightful.
Solecism? An 'eponymous' novel there would be titled Martha Grimes; I am sure you meant it is titled The Knowledge. To mean.'with the phrase under discussion for its title' – if I wanted to be short – I think I'd go with 'thus-titled'.
k_over_hbarc at yahoo.com
John Swindle said,
December 11, 2024 @ 5:35 am
@Andrew Usher: Yes, I meant the novel of the same name by Martha Grimes.
DJL said,
December 11, 2024 @ 5:52 am
@ Stephen
Didn't say Catford is in central London, and that's why I expressed surprise that it would fall within the 6 miles radius The Knowledge is supposed to cover (it's closer to 9 miles if you actually drive that distance).
However, I have had a look at the so-called Blue Book, which has the routes you must master to pass the test (link below), and the furthest those routes seem to go is Lewisham/Dulwich/Sydenham. There are also some suburban routes in there, and Catford is part of one starting in Lewisham, but I don't think that's part of what people call The Knowledge. Anyway, The Knowledge is certainly mostly about central London – or zones 1-2 if you must.
https://www.londonreconnections.com/wp-content/uploads/BlueBookAllLondon.pdf
Philip Taylor said,
December 11, 2024 @ 1:38 pm
From the TFL web site, in re becoming a licensed London taxi driver :
† "Additional", that is, to the 320 mandated routes that lie within the six-mile radius.