When I was little I longed to be a nurse. My mother found the ambition wanting and kept on at me to upgrade to doctor or surgeon (brain). As I got older I wanted to be, variously, a vet, a spy, a psychoanalyst, an illustrator, a novelist, a translator and, bingo! — unless you’re my mother, who’s still sobbing hot tears — a journalist. My sisters wanted to be, respectively, a poet and a marine biologist. It’s not that we were Nerd Family — we were/are, in fact, extremely silly and pleasure-seeking.

My friends were the same: they wanted to be “a businesswoman”, a pilot, a ballerina, a teacher. Obviously my contemporaries and I all had pop star fantasies but they involved singing into hairbrushes in the privacy of the bathroom; if we were any good at acting — which some were — we confined ourselves to school productions.

Fast-forward 30 years and it’s not just that people want to be actors or pop stars instead of doctors or lawyers — it’s that they want to be these things even if there isn’t an iota of evidence that they have the merest crumb of aptitude for the job (see the parade of deluded losers who audition for The X Factor).

Research published last week shows there has been a “seismic shift” in children’s ambitions over the space of a single generation. Becoming a sports star, like, er, Wayne Rooney, is in top spot, becoming a pop star is at number two and the third slot is occupied by being a famous actor (teaching, finance and medicine held the top three slots 25 years ago).

Regarding the last two, the combination of reality television talent shows and the abundance of drama or other “performing arts” courses means everyone thinks they can have a go. This is basically insane — a mathematical impossibility. There are many, many more drama students and actor wannabes than there are acting jobs in the entire western hemisphere.

Obviously talent shows must bear some responsibility for this state of affairs, but then talent shows were around in the 1970s, too: Opportunity Knocks was even more of a water cooler (except there weren’t any water coolers) topic than The X Factor or Strictly are nowadays and its participants accrued plenty of column inches. So what’s changed?

Might it be the change in parenting approaches? Here’s an example: when my eldest son was about six, he was determined to be a squirrel when he grew up. I was utterly charmed by this and — “encouraged” is the wrong word because it suggests I set up agility courses in the garden and left nuts lying around in challenging places but ... you get the gist.

At no point did I say, “Actually, darling, you can’t really be a squirrel. It’s not going to happen.” Eventually his ambition moved on and he decided he wanted to play for Manchester United. This went on into his teens. At no point did his father or I say, “Um, the football thing — it might not work out; shall we make a Plan B?” We just bought him football boots and ferried him around to games miles away.

Now, this is nice: I’m not suggesting I should have stamped all over my son’s dreams instead. But, as the writer Barbara Ehrenreich points out in a book that’s just been published in America, there is such a thing as too heavy a rose tint and there are consequences to the more crazed reaches of optimism. In Bright-sided: How the Relentless Promotion of Positive Thinking has Undermined America, the author takes America’s famed sunny outlook to task, tracing its origins “as a marginal 19th century healing technique” to “its enshrinement as a dominant, almost mandatory, cultural attitude”.

Ehrenreich gives both barrels to, among others, evangelical churches that preach that you have only to ask for something to get it because God wants to “prosper you”; and academia, which includes departments of “positive psychology” and examinations of “the science of happiness”. She suggests the whole fixed-grin, everything-is-going-to-be-fine approach is also behind the current financial crisis, which she sees as fuelled by the refusal even to entertain the possibility of negative outcomes, such as mortgage defaults.

Positive thinking, she concludes, has brought us to “an era of irrational optimism resulting in disaster”; after all these years, realism might be a valid alternative. (The book is being published by Granta in the UK in January, retitled, snappily, Smile or Die.) Meanwhile, children want to be Alexandra Burke, who won The X Factor last year. And Burke isn’t happy. The 21-year-old said last week that her success has caused family difficulties: her mother, who used to sing with the group Soul II Soul, has found it hard to adjust to Alexandra’s much-yearned-for level of fame.

“She had Soul II Soul, but it didn’t last as long as she wanted it to last,” Burke tells the new issue of Marie Claire magazine. “Then I get this big new show, I win it and it’s weird for her to see. Although she’s proud, it’s like she wants to rewind time to when she was younger, when she didn’t have kids.” Her 16-year-old brother attempted suicide last summer: “He’s going off the rails ... he needs a father figure.” Stories like this — and there are hundreds of them — do nothing to deter people’s ambitions, which I find weird.

Parents haven’t changed, even if their children have: in the survey they still favour the traditional professions, with the law, medicine and being an entrepreneur topping the tables of careers they would choose for their children. They should perhaps realise they’re hardly likely to get a doctor for a daughter if they encourage her to have unrealistic expectations about her future global pop stardom.

We think we’re being kind, loving and supportive when we tell our children they can be anything they dream of being, but it’s not exactly telling them the truth, is it?

I wonder if it’s a coincidence that the three professions children most long for are the three — sports stardom, pop stardom, acting stardom — that enable adults to remain basically infantilised for life. I suspect it’s got an awful lot to do with being overly cosseted and not ever being willing to give that up.

+ I don’t really understand the luxury jewellery market. Diamonds, for instance. They’re shiny stones. They’re pretty and sparkly, but then so is glass or crystal and if someone is wearing an amazing ring I honestly can’t tell the difference (as for carats: no idea).

I’m not opposed to diamonds — although the people who mine them usually have appalling lives, which I personally find a bit of a turn-off — but I don’t really see the point. What is the point — love expressed through pounds sterling? It’s not really my bag.

So I was amused by the story last week about the £15m giant ruby that turned out to be a £100 paperweight. The (supposedly) 10,000-carat Gem of Tanzania, which had been exchanged for 11m shares in a Shropshire construction company, was on closer examination found to be a big lump of anyolite, an East African type of crystal.

However, the story rather proves my point, which is that precious stones are only as precious as you believe them to be: one minute the Gem of Tanzania is the eighth wonder of the world, the next minute it’s just a lump of rock. Its appearance hasn’t changed, only the perception of it. Wear costume jewellery and spend the money on holidays instead.

india.knight@sunday-times.co.uk

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