I expect Tony Abbott will be panned for his statement yesterday that only the “right” kinds of kids should be kept on past year 10. Parasitic education bureaucrats, welfare apparatchiks and bleeding hearts everywhere will slam him for trying to deny children the opportunity of tertiary education, for not “caring”.

But he is spot on.

Few jobs require the rigours of a university degree, or even six years of high school. Past generations got by perfectly well with three or four years of high school. And apart from the proliferation of computers and the internet (familiarity with which develops outside the classroom), how much has the range of available jobs really changed?

For too long Australia has been gripped by the ridiculous notion that the more people finishing high school, the more people attending university, the richer and more productive our country will become. After all, economic growth occurs alongside growing enrolments.

But I think this confuses cause and effect. The wealth generated by a relatively free economy allows us to spend (perhaps waste) more and more on education. It is a furphy that the quantity of formal credentials determines the quality of the workforce’s skills and knowledge. It is the quality of those courses and the productivity of workers in their chosen fields that matter.

For years governments of both persuasions have poured taxpayers’ money into education; “more money for schools and teachers” is sadly a glib winner at the ballot box. Real spending on education has never been as high.

Yet educational standards, at least the ones that matter to employers, have not improved commensurately. Australian productivity continues to decline. Indeed, some would argue that educational standards today are lower than they were 100 years ago, when hard work, discipline, and memorisation were the only tools in trade.

Universities are offering remedial writing courses for recent school leavers, who couldn’t parse a sentence in English to save themselves. The mathematical content of introductory economics and science courses, for example, has declined.

People out of the workforce in training are a cost to society, unless they are pursuing a qualification that enhances their long-term productivity.  Only then can one mount an argument for a public subsidy. That cost also entails their absence from the workforce: the practical skills they would have acquired and their output forgone.

Yet so many courses at university, and optional subjects in state secondary leaving certificates, confer next to no benefit on students beyond a false sense of social superiority. They are mere consumption, the educational equivalent of a big night out, offering society no economic benefit. Andrew Norton, of the Grattan Institute, has suggested median incomes for arts graduates are similar to those holding a vocational Certificate III/IV.

A key purpose of education is to give students a chance to signal their aptitude and diligence, rather than to acquire knowledge for later vocational use. Fostering longer stints in formal education, of sometimes patchy quality, has done nothing to stymie the need for discrimination. In fact, it has made it more difficult for the brightest and most industrious to reveal themselves to potential employers.

Where once a single bachelors degree would have been sufficient to signal one’s ability, now two, three, even four degrees are required. Some of our potentially most productive workers effectively don’t finish school until they are 30, their truncated work life yet another (unmeasured) cost of our misguided education fetish.