What would you have done if you hadn't gone into teaching?
I was going to be a brewer. When I finished my degree at Cambridge I was ready to join one of the large brewing companies. But when I got near to it I had a fit of idealism and questioned if it was really what I wanted to do.
Who has been your biggest professional influence?
My father was a chemist; he was a lecturer in fuels and explosives at the Royal Military Academy in Sandhurst. I got into it very young.
What has been your career high so far?
Being knighted. But I have also had quite a lot of letters and emails from people I taught as long ago as 20 years saying: "I saw your name and wanted to write to you and say that you are the reason I'm now a career scientist."
Where did you last go on holiday?
I went walking in Ribblesdale in the Yorkshire Dales.
What was the last book you read?
I have just been reading Herodotus: The Histories. He wrote about the war between the Greeks and the Persians. I find ancient history absolutely fascinating.
Are you tech savvy or a luddite?
I'm reasonably tech savvy. Technology enables me to do things, but I wouldn't get new technology for the sake of it.
What is your biggest regret?
I don't think I have got any regrets. I like being where I am and feel that I have been very fortunate in my life, both personally and professionally. If I had done anything different, my life wouldn't have ended up as it has.
Who would be your ideal dinner guest?
What is the first thing you do on a Friday evening?
Have a nap.
What website do you use the most?
My homepage is the BBC. It's superb for keeping up with what's going on in the world.
Are you an early bird or a night owl?
Early bird. I'm up at six.
Interview by Meabh Ritchie
Sir John Holman is director of the National Science Learning Centre, which provides professional development support networks for teachers by helping them to explore contemporary scientific ideas. He is a former secondary school chemistry teacher.