The long-haired lecturer from the late 1970s made a very different impression when he returned to present outstanding achievement awards at his old college, the City Lit, on Monday.
The dark mane was replaced with a few wisps of grey. The shaggy beard was now close-cut. And the large frame of 25 years ago had swelled to even greater proportions.
But the voice was unmistakable as he reminisced about the two years he spent teaching part-time at the college in Covent Garden, London.
Charles Clarke, the Education Secretary, told the audience at the ceremony at the British Museum: "I owe a personal debt to the City Lit. It was the most stimulating educational experience of my life."
He recalled that he taught a Fresh Horizons course designed to help adults who left school without adequate qualifications to prepare for university.
"I wasn't a very good teacher but I taught maths," he said. "What the course taught me was that we had a group of people, mainly women, who had left school at 16 deciding that education hadn't much to offer them at that time.
"Maths was a subject they didn't all enjoy instinctively. My job was to persuade them that education was interesting and useful. But I learned more from them than they did from me.
"It was genuinely inspirational because if people could see things as they were in a different way, then education could transform the way they looked at things."
One City Lit lecturer who was part of the Fresh Horizons team with Mr Clarke remembers him well. Linda Dicks, who teaches social studies, said:
"He was remarkably different in those days. He was very left wing and an idealist. We all were."
The Education Secretary and Alan Tuckett, director of the National Institute of Adult Continuing Education, presented awards to 35 City Lit students and six groups who have been nominated for Outstanding Adult Learners Awards.
Mr Clarke said: "All education is about giving people the confidence to educate themselves. With confidence everything is possible. It was very much the case that teachers were a tremendous source of support and encouragement. That everybody is a student always is very important. I wish that approach to education was more widespread. Everybody, whatever their circumstances, has had to overcome issues in their own lives. Everybody has the capacity to learn and educate themselves.
"The City Lit taught me that everybody has things to learn and can benefit from education and gain the confidence to tackle the problems in their lives."
The award nominees exemplified that sentiment. Learning Works award winner Gary Haines told the audience: "I owe Fresh Horizons a debt I can never repay."
He left school at 16 but later developed a passion for history, has had one book published and two commissioned, and now works full-time as an historical archivist after gaining a BA in history.
Connie Silvester won an Outstanding Adult Learner nomination after a lifetime of taking City Lit courses. Now in her eighties, she first took a painting course in 1948 and has just completed a City and Guilds course in woodcarving.
Richard Brown suffered a speech impairment after he had a stroke at the age of 37, took a Getting Your Confidence Back course, and is now an advocate for people with communication difficulties.
The City Lit is London's biggest provider of part-time learning for adults, offering more than 3,000 courses to 23,000 students.
The awards are a national event, part of Adult Learners' Week, organised every year by NIACE.