We've looked at Johns' arguments about this subject - the need for Standard English and the dangers of street slang to inner city youths - on this blog before and, to be honest, much of what he says in the Four Thought lecture is a slightly reheated version of his older articles which you can find here and here.
Unlike Johns, who sees the issue in stark terms - Standard English = good, slang = bad - the issue is more complicated than he suggests. I think he probably realises that, but why let research, reality and facts gets in the way of a good rant? And hey, it seems to be doing him some good, as he gets to stand on stage among an overwhelmingly white, pensionable and right wing crowd and denounce lefties to big applause.
One of the stand-out moments in his Four Thought piece (apart from the Stevie Wonder joke - Stevie Wonder is blind? LOL!) is his hugely overstated attack on white, middle class liberals, who espouse a doctrine of "cultural relativism" in which all language styles are just as good as each other and where street slang is viewed as the authentic voice of the streets and therefore not to be discouraged.
Instructively, he doesn't name a single one of these sinister lefties, or tell us about a single paper, article or case study that they've produced to make such a claim, but he reaches heights of rhetorical flamboyance in making these claims:
Contrary to the risible notions promulgated by cultural relativists - often white, liberal, middle class ones - notions which are deeply patronising, obnoxious and offensive, not to mention viscerally racist, of accepting black kids from Peckham speaking in inchoate street slang because they deem it to be the "authentic rhythms of Africa", I tell my mentees "We don't live in Timbuktu, or the south Bronx; we live in England, so speak proper English".For a man who likes teaching young people how to use adjectives, he sure uses a lot of adjectives...
But, as I stated back in 2011 in the response to his original ghetto grammar piece:
Firstly, you'd be pretty hard-pressed to find any linguist or educator who doesn't argue that a mastery of Standard English is a prerequisite of a good education. Who are these cultural relativists that Johns is referring to? It smacks of the right wing arguments about the "PC brigade": some nebulous and sinister cabal of liberals and lefties hell-bent on messing up everything about young people's education with their crazy commie views. They don't really exist...While Johns is clearly right to say in his articles and lectures (and yes, even his speech to the Tory conference) that "language is power" and that some of the most marginalised and underprivileged in our society desperately need that power more than their pampered Eton-educated counterparts (err, not that he said that at the Tory party conference), he's spectacularly wrong in claiming that slang is the problem.
Secondly, code-switching is not that difficult for young people. They do it all the time. But only if they have another form to switch into. That's essentially the point that Johns is missing. The young people he works with - if they have as poor a command of Standard English as he claims - don't have a problem with slang: they have a problem with basic literacy. To lay the blame for these young people's inability to write and speak clearly at the door of street slang and those people who don't condemn it out of hand is a very weak argument.
Yes, there may be some young people who struggle to grasp a sophisticated level of Standard English - that has pretty much always been the case and we should strive to help them - but there are many many more young people who know exactly how to code switch when they use language in different situations and who know exactly when and when not to use slang and the value of that slang.
In attacking street slang, Johns misunderstands the real power of language: its ability to serve us in different situations and with different people and to convey a massive range of different, nuanced attitudes. Language is power, but rather like in the anecdote Johns tells us about being pulled over by the police and bamboozling the Met copper with the word "abstemious", Johns seems to equate power with the superficial quality of knowing a few more adjectives than the next guy. Really? Is that it? If anyone is patronising young people, it's not an anonymous collective of liberal lefties but Johns himself.