For almost 50 years Richard Morris Brown has been quietly working away at his two passions: metaphysics and painting, his ideas on the ‘nature of being’ inspiring his art and his free-flowing paintings helping him work out complex philosophical ideas.

Now both have burst forth into the world, the first as a self-published book, Something to Believe, the second as the opening exhibition in a new series of St Albans pop-up art shows.

“It’s just a bit nerve-wracking because the art I do is quite personal,” says the 75-year-old who will show 30 pieces dating back to the ‘70s.

“When I was painting it I never really thought about it being displayed but deep in my heart I supposed I hoped one day it would be seen.”

Originally from Yorkshire, Richard had an interest in art and metaphysics, which he says “bridges the gap between the rigour of science and the whims of faith”, from a young age.

But with a “choppy” upbringing – “My father died when I was seven and my mother was certified insane when I was 15” – he admits he has suffered with self esteem issues when it came to sharing his work.

“I have got some quite radical ideas, and people are wary of that, such as words like infinity and nothing being meaningless. You can’t point at anything and say it’s nothing. The art is a way of working with these ideas.”

Then along came Sam Sawdy from M-Sieve Art and with him the idea for a pop-up exhibition of Richard’s work, which has quickly grown into a seven-week showcase of 20 artists.

Richard, who was head of the education department at Holloway Prison for 25 years, creates his artwork, mostly in bold poster paints, by simply painting what he feels.

“I just begin with a blank canvas and place a mark using a pencil and then think and then make another mark and it builds up. Very often I don’t have a clue what it’s about, it just all comes from my subconscious.

“I was tentative at first and ashamed of it as I thought people would say ‘what are you doing with those odd shapes and colours?’ but I have grown more confident.”

He adds: "I don't want it to be analysed too much as that kind of negates it. It's just to be absorbed."

M-Sieve Art Gallery, Hatfield Road, St Albans, from November 1 to 9. Details: 07870 941158, m-sieve.com, universetheory.com