In art, as in science, some of the most thoughtful, pioneering minds work away quietly in their studios or labs for decades before the world catches on to what they are doing. For nearly 30 years – from the late 1940s to the mid-70s – François Morellet, a self-trained painter, ran his family’s factory in Cholet, western France. Come the weekend, he was quietly inquiring into the nature of subjectivity in art – or as he describes it, 'flirting with the void'.

'When your goal is to say nothing, it is easy to do so, but the biggest challenge is to let people know about it,' says Morellet, as he prepares a series of exhibitions in London and Brazil to mark his 90th birthday. Now, at last, his early pieces of radical minimal and conceptual art are recognised by the establishment, and hang in major collections including the Tate Modern and MoMA; and his international reputation is growing.

He is wryly philosophical about his late success: 'I often said that in the past, I considered that my work was widely underestimated and that today it is probably overestimated. Injustice can be quite bearable, especially when it favours yourself.' This attitude, of standing back from his own success and observing it with a scientific, politicised coldness – yet always with a warm, humanising wit – is typical of the attitude Morellet has always taken to art.

In the early 50s, reacting against the values of the day, Morellet began to experiment with painting and printing methods that used systems to minimise the sensibility of the artist, and 'make work as empty as possible'. He explored an aesthetic dictated by both mathematical rhythms and chance, producing works like, Random Distribution of 40,000 Squares Using the Odd and Even Numbers of a Telephone Directory, 1960. Pre-dating the minimalist movement, he took as aesthetic inspiration his love of free forms like jazz and the apparently infinite motifs used in Oceanic tapa fabric designs.

Morellet later embraced neon tube lighting and installation art, always looking to reject art historical baggage with fresh forms, materials, and even language. When I asked Morellet if he created work in response to architectural spaces, he said he was allergic to the word 'create'. 'As far as I am concerned I amuse myself playing with constraints that I establish with my systems. Playing with "rules of the game" is the most efficient way to reduce my subjective decisions which is my first and final goal. Playing with architecture saves me the trouble of using my own constraints.'