After leaking plans to the Daily Mail last week to scrap GCSEs, Michael Gove was both denounced as an inhumane Victorian and welcomed as a one-man panacea for all Britain's social ills. Broadly, the former tendency came from the left and the latter from the right. This represents a terrible defeat for the left, and I say that as someone who is not a conservative.

Perhaps the greatest failure of the modern centre-left in Britain is its connivance in the systematic dismantling of academic education in the state sector. This has been done under the guise of vocational education, a secular tyranny which consigns the poorest students – or at least those forced down this path – to a life of diminished learning and stunted imagination. It has led to a terrible chasm in our society, which I wrote about in The Independent two years ago: skills for the poor and schools for the rich.

If you go to the great public schools around the country, or speak to its progeny, you will note that all sorts of specialist, skilled activity – woodwork, cooking, sport – is complementary to academic learning, by which I mean crunchy subjects like physics, maths, Latin, and history. It is not a substitute. This is because, in the schools that produce the most intellectually able students – and I know how contested is the measurement of intellectual ability – they know that it is tough academic subjects – organised bodies of knowledge transmitted through the generations – that learning is cultivated.

The expansion of vocational learning in the past 15 years was a way of palming off struggling poor students on to subjects that kept their attention. But there are two massive problems with this approach. First, adolescents don't know what's good for them, and in any case their interests are temporary and transient. At 14, I wanted to be a porn star, a cricketer, and a train driver (in that order). You can be the judge of how that worked out for me. Second, if a pupil from a poor background specialises in textiles at 14, and realises two years later he doesn't want to be a clothes manufacturer after all... then what? Better to have tried and failed at tough subjects than head down a blind alley with no turning back.

Vocations are fine, even laudable. But they should complement, not substitute, academic learning – and therefore be reserved for those over 18. I cannot tell you whether or not Gove's adoption of a Singaporean system is a good idea. But I do know that when people on the left instinctively denounce any plan to restore academic rigour to the state sector, they are going in for the very class warfare they used to despise.

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