“Knowing” a language is too vague a term and even if we agreed here what we mean by it, that wouldn’t have any meaning in the wider world, where it would remain vague.
On the one hand you have people like me who can say you don’t really know a language until you are really intimate with the way it handles all manner of nuance and situation, in the way you can be said not to fully know your wife or husband after forty years of marriage. There used to be a show in which married couples would be quizzed about each other and some surprises would come out about things they didn’t know about each other, this was the whole premise of the show and I believe that similar content has been on the TV or radio channels of most countries.
Then you have the 80:20 approach, where you get 80% of what a native of similar intelligence and education to you would have of his language, but Vilfredo Pareto, that famous Esperantist, discovered by throwing his pocket money onto a table that this only takes 20% of the time it would take to actually get as good as that equivalent native speaker, in the language.
I tend to aim for this kind of thing, if I get to be 80% as good in the language as my equivalent native speaker, then I can already communicate as sophisticatedly as I like and that ENS will take up the slack. That way, I get 5 languages for the price (the ‘time-price’) of one, which is a good bargain and also highly usable.
A lot of people using English comfortably in international business are at something like the 80% level. Whether they used the time saved to learn four other languages to the same good but incomplete level, learn some other thing, do more business or just spend more time with their guinea pigs is up to them.
Further down the scale you have people who claim to know 20 or 30 or 80 languages. These are the polyglot equivalents of social networkers who have contact lists well in excess of the Dunbar number. For those who feel “dunbar” than they did before when I say that, I am referring to the lovely gentleman in the featured image, Professor Robin Ian MacDonald Dunbar, the head of Experimental Psychology at Oxford University. Some people say he is the one Diana Gabaldon had in mind when creating the character Roger Mac in the Outlander series. He represents the theory (more than an opinion, as he has got lots of data and it’s all been per reviewed and that) that humans can have meaningful and stable social relationships with somewhere between 100 and 250 people. Most typically this number seems to peak at about 150 people. I have to say I personally have little resonance when it comes to this theory, as I have a social media network which extends to (at the last count and I count it once a quarter) a little over 12,000. Allowing for the overlap between Facebook and LinkedIn that would still likely be over 9,000 being conservative.
Now continuing this analogy between knowing languages and knowing people, the 9,000 maybe symbolises the languages which there are in the world. How many there really are is probably fewer than that by now, as languages have a tendency of going extinct before they even achieve literacy and an archive. Manx and Cornish are among the lucky ones. I reckon there are probably something more like 1,500 which could be learned without recourse to field linguistics and a lot of malaria shots. There are currently 1,353 languages in the Gideons Bible App (my hearty and ongoing recommendation to all interested in the Bible and in languages, and it is free of course, and contains plenty of audio – available on all good App stores) and I am kind of going on that and things also I read in SIL resources. A lot depends on how you place the cut-off between what is another language and what is a dialect. There are more difference between forms of English and Arabic than there are between some clusters of two, three, four or more languages recognised as being separate. There are various tests for this, but in practice no overall consensus seems to have been reached, and of course politics rears its Gorgon’s head and turns objective thought to stone at regular intervals.
Then let’s consider analysing this into the people who asked to connect with me and I agreed, but probably if I cleared them out it wouldn’t make a great deal of difference – well I did at one point produce a cut down database of my contacts (pre GDPR, you understand) and the people I considered valuable contacts that I means to be able to email and phone with ease came to around 800 and now it may be more like 1000, so really maybe only 10%. This, in my languages/people analogy, is a good equivalence to the long lists of “Languages I would like to learn” which some of the less powerful intellects in the Polyglot universe seem to feel compelled to posting from time to time. Yes, we probably all would like to have the time to look at to a greater or lesser extent 10% of the languages that there are, listen to 10% of the songs there have even been, watch 10% of the movies, read 10% of the books, but because there are so many in reality we are going to cover a much smaller sample than that, whether we be persons of leisure or fanatically careerist sarariiman who take inemuri rather than reading breaks because they are too tired, and take zero leisure, apparently.
Of the 800, I would say that I know to greet on the street from the LinkedIn list 500 and another 500 from the facebook or YT side, and as far as really writing on a regular basis is concerned, sending memes privately, playing Quiz Planet or ItsYourTurn and chatting in a way that gets to know even a faceless person, maybe 300. But this is because I make an effort. This may represent the languages that an ambitious polyglot learns a few words of, learns maybe the Korean hangul, learns a bit of Koine to read some passages of New Testament, knows a few words or sentences of for touristic purposes, or looked at for philological research.
When it comes to actually knowing people very well, as it knowing how they will react in a certain situation, it is just a handful of people. And the same goes for languages.
And then you have to wonder whether you really know any person, or language, at all.
So in summary, the whole use of the term “knowing” a language is unhelpful, and I would simply refer the gentle reader to the sentence of Socrates via Plato: “ἓν οἶδα ὅτι οὐδὲν οἶδα“, or “All I know is, I don’t know Jack”.
And for sure, we all do know a lot less than we think we do.