Dr Nick Axten, now 76, said he needed “a long hard think” over the more than 50 intervening years.
In 1970 Dr Axten received a prestigious Fulbright scholarship for a PhD in mathematical sociology at the University of Pittsburgh. But after five years he returned to the UK with the PhD unfinished.
Today the University of Bristol conferred him a Doctor of Philosophy in front of his wife Claire Axten and 11-year-old granddaughter Freya.
Dr Axten said: “What I was trying to do in the early 70s was exceptionally difficult.
“Some problems are so great it takes the best part of a lifetime to get your head around them. They need a long hard think. This one has taken me 50 years."
Dr Axten’s research, which he hopes to publish, builds on the ideas he was working on in America five decades ago. It is a new theory for understanding human behavior based on the values each person holds. Dr Axten says it has the potential to change our view of behavioral psychology.
When he started his undergraduate in Leeds in 1967, men wore their hair long and women were wearing miniskirts.
Smoking inside university buildings was the norm and personal computers were still sci-fi.
“It was still flower power and there was a revolutionary feel. It was the time of the Vietnam War, Paris, Prague and student sit-ins. Jack Straw was president of the students’ union in Leeds,” he remembered. “Sociology and psychology were suddenly boom subjects. I went to study them because I wanted to understand people.
“I have loved being a student again at Bristol University. All of the other philosophy graduate students were around 23 but they accepted me as one of their own. They are clever people full of ideas and I loved talking with them – especially at the pub in the afternoon.
“Doing a PhD is a lot of hard work, but it’s been brilliant.”
Dr Axten came to the University Bristol in 2016 to do an MA in Philosophy, aged 69. He then studied for a PhD in Philosophy at the same university, finishing in 2022 aged 75.
His University of Bristol supervisor, Professor Samir Okasha, said: “Nick was an incredibly enthusiastic, energetic and committed student during his time here.
“It’s fantastic to see him graduate half a century after he started his original PhD.”
During a varied career Dr Axten lived all over the UK and was creator and principal author of the school teaching programme ‘Oxford Primary Science’.
He lives in Wells, Somerset, with his wife and is father of two children and four grandchildren.