There is also a second campaign that we must fight. That is the battle against creeping selection. It may well be that there is much to be gained from comprehensive schools that develop a speciality - music, art, drama, mathematics. But there is nothing to be said in favour of allowing those schools to select a proportion of their pupils.
The inevitable result is a hierarchy of esteem. And we know, as a certainty, that once schools are listed in some sort of pecking order - no matter how arbitrary, ignorant or malicious it may be - the morale, the intake and the performance of those at the bottom of the imaginary league table inevitably declines.
Yet the Government somehow thinks it right to allow, indeed to encourage, what it calls selection by aptitude. With a fine disregard for its intellectual reputation, it even chooses to pretend that selection by aptitude is different from selection by ability. Yet we know that both processes produce the same result.
The little boys with violins and the little girls who have music lessons and take their places in selective specialist schools are the children who are coached to win grammar school places through the 11-plus. Jean Floud told us years ago that "There's always a social element in selection." It will prejudice the entry into the specialist schools, as it did and does into the grammar schools.
However, I don't want my part of the rally to turn into an attack on Government policies. The best prospect for complete comprehensive education in this country still lies with the Labour Government. Our task is to turn the prospect into reality.
Our greatest weapon is the strength of our case. We know that comprehensive schools work. For gifted pupils; for average pupils; for pupils with special needs. The improvement in the overall level of education in this country - demonstrated by every objective measurement - is the triumph of the comprehensive system that educates 90 percent of our children. And almost all the failures - the problems that are trumpeted in our newspapers - occur in schools that are only comprehensive in name. They are old secondary modern schools in which the only change has been the name. They are schools that are denied the stimulus of talented pupils and the esteem that they bring because 10 per cent of the school population has been siphoned off into grammar schools. And then the grammar schools have the gall to say: "Look how much better our examination results are."
I believe that many of the existing grammar schools' pupils achieve far less than they should. And I am absolutely certain that they damage the prospects of the schools that surround them. It is nonsense to ask, "Why bother about 166 selective schools, when most of our schools select no longer?"
Every grammar school prejudices the prospects of certainly six and perhaps a dozen of the schools around it. Unfortunately, the Government that claims to support the comprehensive ideal seems not to understand that selective and comprehensive schools cannot exist side by side. They are mutually exclusive.
Talk about a semi- or partially comprehensive system is no more rational than the description of someone as partially or semi-pregnant. Comprehensive education is a state, not a condition. You either have it or you do not. Thirty-six local education authorities do not, with immense penalties for the majority of children in their area.
In Birmingham, the city I once represented, education was depressed by two factors - lack of resources, and the King Edward's Foundation of selective schools. The council could remedy the first detriment but it could not remove the second. Our immediate task is to campaign in those areas where the grammar schools remain.
So today we send a message to all parents who support the comprehensive ideal.
The intellectual argument is on your side. You are not alone. The numbers, as well as the merits of the argument, are on our side. Over the next year we have to mobilise the thoughtful majority against the minority who believe - often wrongly - that they can steal a march on their neighbours.
The Education Minister, Stephen Byers, told us that the grammar schools would go when there was a groundswell of opinion against them.
Today we meet to begin the campaign that will bring that groundswell about.