His lecture on Tuesday at the London Institute of Education was given on the 20th anniversary of his landmark Ruskin speech, which launched the “great debate” on education and opened the secret professional garden to the uncomfortable glare of public scrutiny. Most of the anniversary speech adroitly combined a tactful endorsement of current Labour party policy with deeply held personal convictions, but the sting came at the end when he pointed out that money recouped from the abolition of the Assisted Places Scheme, Labour’s only definite financial commitment on education so far, would be a mere drop in the ocean.

“I do not blame Gordon Brown for refusing to allow the Conservative party and the media to pin him in a corner on tax increases,” he said, “but he will be in no doubt that a big bill must be paid if Britain’s children are to have the high level of education and training that will be needed in the 21st century. ”

Lord Callaghan, now 84, reminded the audience that his own interest in education reform had been engulfed and frustrated by the economic crises of the late 1970s.

The next Labour government should first “put before the nation an all-round panoramic view of what Britain’s educational future is to be”, and then aim to carry it out in instalments, starting with universal nursery schooling and an attack on disadvantage, taking care meanwhile that “hope should not be so long deferred that disillusion sets in”.

Lord Callaghan remarked that when he re-read his Ruskin speech recently, “it was hard to see what the fuss was about”. Now that education is dissected daily by politicians of every hue, younger members of the audience must have found it difficult to comprehend that in 1976, a Prime Minister’s right to trample on teachers’ professional domain by raising questions about schools was hotly disputed. If this was the most dramatic change since ‘76, many of the other problems he raised then, he said, are still to be solved. “Let us stop tinkering with school structures, such as bringing back grammar schools, promoting selection and other gimcrack ideas,” he urged. The education service should concentrate on raising achievement among the majority of children of average ability so that nobody leaves school without the basics needed for employment. Toeing the new Labour line, he endorsed specialist schools, condemned selection while supporting streaming, advocated co-operation with private schools while hoping that they “wither on the vine”.

“The battle for higher standards will be won only if we can enlist the teachers as full partners”, he said, adding that a General Teaching Council should be set up as a statutory body established by Act of Parliament.