Dr Andrew Norman (Letters, 1 July) “calculates” that, had the 11-plus examination been retained throughout the UK, there would now be 7,800 grammar school-educated undergraduates at Oxbridge and that, on this basis, 25,200 state-educated pupils have been deprived of an Oxbridge place during the past 40 years.

Unfortunately for Dr Norman’s theory, there are actually more than 10,000 state-educated undergraduates currently at Oxbridge and the proportion of such students has risen from 37 per cent in 1964 - the heyday of the post-war grammar school - to 56 per cent in 2010.

Indeed, Oxford is about to admit its highest ever proportion of state-educated pupils.

Ironically, Dr Norman’s naive and simplistic calculations lead to a conclusion which is the exact opposite of the one he wishes to draw: the sooner selection at 11 is completely abolished, the better.

Michael Pyke, Campaign for State Education, Lichfield, Staffordshire.