Reading a column in the Independent this month on the Education Bill, I came across a statement so extraordinary that I reread it three times to make sure I had understood it correctly and not missed some hidden ironic intent. I also scanned the readers' letters keenly for several days, expecting somebody to dispute the statement. Even more amazingly, nobody did.

The column was by Deborah Orr, whose work I usually admire, and this is what she wrote about a school (unnamed) in the London Borough of Lambeth, where she lives: "Last year 47 per cent of pupils had passed five GCSEs at A* to C grade. This . . . means that 53 per cent left the school functionally illiterate."

Illiterate? The Independent runs a rather odd, but riveting, column on Saturdays in which Guy Keleny, guardian of the paper's style, highlights misused words, grammatical errors, instances of jargon and so on in its pages. The use of "illiteracy" should be drawn to his attention. GCSE grades A* to C are the equivalent of the O-level grades awarded when I was at grammar school 45 years ago. Less than half of my pre-selected fellow pupils managed five O-levels. Today I know university tutors who, at first sitting, got fewer than five top GCSE grades. I accept that some say exam standards have fallen, but surely not to that extent. I accept, too, that Orr used "functionally" as a qualifying word, but she uses it too imprecisely to convey any meaning. She is saying, in effect, that most Britons can't read: a preposterous statement.

I would forgive her - we all say daft things at times - if it weren't symptomatic of a wider phenomenon. This is the rise of a commentariat who express opinions that have no basis in knowledge. Twenty years ago, academics, professional practitioners or a paper's own correspondent would provide a fair proportion of comment. On an education bill, for example, the education correspondent would often be the main source of analysis. On new Labour's current bill, however, I can remember only one article by a specialist - Matthew Taylor, the Guardian's education man - and very good it was, too.

Otherwise, specialists have been largely usurped by "star" columnists and professional "why, oh why" hacks who purport to know about everything from bird flu to the situation in Fallujah. Only a few root their opinions in a broad specialist field: for example, the Guardian's George Monbiot (environment) and Polly Toynbee (health and social services), the Independent's Hamish McRae (economics), the Telegraph's John Keegan (defence) and some political columnists. Most commentators are generalists, sometimes drumming up an opinion after half an hour on the net. This kind of comment reaches its apotheosis with the Daily Mail's Melanie Phillips, who claims to understand more about global warming and MMR vaccines than all the world's scientists and doctors.

There are good reasons for the rise of the commentariat. Academics are less adept at writing for wider audiences than they once were. (The reasons for this would need another column.) Writing a 1,200-word "think piece" - or "thumbsucker", as the rougher reporters call it - is, in some ways, an art form that only a minority even among journalists can master. And specialist reporters, who get their news stories from specialist contacts, are vulnerable to "producer capture". Education correspondents, for example, tend to see sense in what teachers' unions (dread words!) say and to pull their punches for fear of upsetting people they meet daily.

Yet if more comment-page contributors had to face the people whose work they write about, they might hesitate over their more ridiculous remarks. Orr was writing for her editors (as all journalists do) and for her metropolitan middle-class friends who are always moaning about the capital's schools. This "voice of the consumer" - the parent's voice in education coverage - now dominates the political and media culture. But I take the view, which some would call patronising, that newspapers should strive to do more than echo ill-informed prejudice.

I regret to report that Sarah Sands, after little more than eight months, has departed the editorship of the Sunday Telegraph. I always feared that her attempts to spice up this stuffy old paper with pictures of gay kisses, stories about Austrian villages called Fucking and call-girls' diaries would get her into trouble.

I expect her successor, the serious-minded and rather prim Patience Wheatcroft, who comes from the editorship of the Times business section, immediately to put one of her long stilettos into the paper's remarkable series of readers' letters on beating girls' bare bottoms. I drew attention to this exciting innovation two weeks ago. The correspondence has continued, taking it to a sixth consecutive week, which must be a record for any letters-page subject. But I will spare readers further details: those who want that sort of thing know where to get it.