‘The great goods cannot always live together.’ That was Isaiah Berlin’s dictum. The current debate about grammar schools reminds us of its truth. Underlying the question of choice, there is an unbridgeable philosophical divide. If most of the grammar schools had not been abolished, a lot of children whose parents could not afford to go private would have had a much better education. But an even larger number of children who received a competent education in comprehensive schools would have been condemned to durance vile in grim secondary moderns, with seriously diminished life chances. So who should take priority, the many or the few?

Looking back, everything could have been handled better, and the much-lauded Butler Act of 1944 does not deserve its reputation. It had numerous and related flaws. The first was the aim of tripartite secondary education: grammar schools, technical schools and secondary moderns – all enjoying parity of esteem. Utter baloney. There never was parity. There was an abyss between the grammar schools, some of them ancient foundations with a long-mellowed patina of prestige, almost all of them occupying handsome buildings surrounded by playing-fields – and the secondary moderns in lowering breeze-blocks with all the grace one would expect from rapidly constructed low-cost buildings in the austere post-war years: cheap schools for cheap schooling. Second, there was no serious attempt to create a technical school sector. Finally, the vital segregation, on which so much depended, took place on the basis of an exam which children took at the age of 11.

There was also a political problem. Until 1944, the lower-middle classes could buy therir children’s way into grammar schools. But once Butler abolished fee-paying, everything depended on the 11-plus. Eleven year-olds had only recently stopped playing snakes and ladders. They were now reintroduced to the game, with the highest of stakes. There was a big snake which carried its victims all the way down to the proletariat. That explains the Tory party’s reluctance to defend grammar schools and resist the march of the comprehensives. Some Tories convinced themselves that comprehensives would be grammar schools for all. Others, less naive, were doubly cynical. On the one hand, they wanted to appease Tory voters: on the other, what did it matter to them personally? Senior Tories of that generation would never have dreamt of using the state system for their own children.

There should have been an alternative to Butler, which had only two routes: grammar schools and technical schools, The latter group would offer high-grade education with a vocational bias. But its abler children would not be cut off from history, literature, the arts, music, science and modern languages though the classics would be left to the grammars. Selection would take place at thirteen or fourteen, and the technical schools would enjoy parity of resources. After all, it would be more expensive to equip their classrooms than the ones specialising in Caesar’s Wars.

Seventy years on, there has been some necessary updating, thanks to one truculent visionary idealist and three practical idealists (if that sounds like a paradox too far, wait and see). It is extraordinary that Michael Gove is now widely regarded as a Jacobean villain. In reality, he is at least as idealistic as anyone in post-war British politics. In particular, he cannot bear the thought of children being condemned to second – or third – rate education. Alastair Campbell once referred to ‘bog-standard comprehensives’ To be fair, he did not approve of such schools – but there was no urgency in the disapproval. That was reserved for selective schools and public schools. Mr Campbell gave the impression that he could live with bog-standard education, as long as everyone had one.

This was anathema to Michael Gove. The idea that bog-standard schools were continuing to fail their pupils during his period as Education Secretary; his response was pain and rage. No wonder he was often such a difficult colleague, like a bull who always carried a china shop around with him. No wonder he had to be moved; he was too emotional to win the confidence of many good teachers and concerned parents, who ought to have been on his side. Mr Gove will not be happy until all children in the UK have the opportunity to develop their potential. George Bush said ‘leave no child behind.’ That summarises Michael Gove’s core belief.

The first practical idealist, Davd Cameron, is not far behind. He has always been interested in education. After the 2005 Election, Michael Howard offered him his pick of Shadow cabinet portfolios. He chose education. Over the years, there had been mutterings in the Tory ranks about the need to bring back grammar schools. They would have been louder but for one awkward fact. Which Education Secretary closed down most grammar schools? Margaret Thatcher.

Mr Cameron’s response was simple. He too wanted more grammar schools. Indeed, he wanted one in every…school, by using streaming and setting to ensure that able pupils were stimulated and stretched. But he regarded the mass reintroduction of grammar schools as a snare and a delusion. Of course any such proposal would win instant popularity, because all parents would assume that their beloved brats would win places. Then reality would intrude.

Imagine a town with four schools. One becomes a grammar, to universal applause. When people grasped the point that the grammar would only cater for one in four, the clapping would subside. Meanwhile there would be wholesale dislocation. Most of the town’s best teachers would scramble for posts at the grammar, even at the cost of cuts in rank and pay. This apparently generous strategy would turn into an exercise in bureaucratic chaos and educational pessimism. Instead of leaving no child behind, the outcome would be lifeboats for a minority, disappointment for the majority.

David Cameron saw no alternative. There had to be a battle to raise standards in every school, for every pupil. Academies and free schools were part of this, but the government never lost sight of the great goal: enhanced life chances for all. The other practical idealists, Kenneth Baker and the late Ron Dearing, were using the same hymnbook. The aim of the Baker/Dearing Academies was to offer high-level vocational education at 14-plus. That is a much more sensible age for parents and children to make important choices as to the best form of curriculum. Ken Baker is insistent that there will be no second-best about his schools. They will demand parity of esteem as of right, while ensuring that the pupils earn it.

In view of all this, the call for new grammar schools might be seen as a side-show. There is surely no harm in allowing existing grammar schools to expand and even to opening a few new ones. But it would be absurd to pretend that this is the answer to Britain’s educational needs.

There is a further problem: a trap into which Tories have fallen. Social mobility sounds like a laudable aim. Who could object to measures which would allow able people to rise and prosper? It is also amusing to steal Left-wing catch-phrases, such as social mobility and social justice. But these phrases also have Left-wing baggage. They come perilously close to positive discrimination. Even Michael Gove slipped over the edge, at least on one occasion, when he complained that five Old Etonians, plus George Osborne, a mere Pauline, would be writing the 2015 Tory Manifesto. But they just happen to be among the ablest politicians and advisers of their generation. It would have been absurd to refuse to use them because they were OEs.

After 1945, in the Soviet Empire, many able people faced hardship because they came from a bourgeois background. They were denied the careers which their abilities deserved. The authorities justified this in the name of social mobility. Michael Gove, a Scot, is no doubt proud of the Scottish education traditions of yesteryear, which enabled the lad o’pairts to show his paces. But that was social mobility by effort and ambition, not by quotas.

So wise Tories should be cautious when talking about social mobility. Opportunities spread as widely as possible: yes. Outright war on the bog-standard comprehensives: yes. Careers open to talent: yes. That said, the key word is talent. Individuals must be given the chance to succeed and to be judged on their merits. But merit must prevail, not social categories. Tories should demand that the clever individual is allowed to strive and rise, whatever his race or background: that excellence is rewarded – even among Old Etonians.