SIR Denis Mahon, art historian and collector of 17th century Italian master paintings, opened a can of particularly stubborn worms on Monday.
He announced that he intended to leave most of the paintings in his £25 million collection to a number of Irish and British public galleries. But the octogenarian wrapped up his gift in a very stern clause.
One of the conditions is that if any of the receiving galleries in Britain sells off works from its permanent collection, the Mahon bequest will be withdrawn.
The uncompromising - and to some, high handed - terms of the bequest are an indication of Sir Denis's passionately held belief that art should be enjoyed by everyone and should be freely accessible to any member of the public.
Over the years he has been a vociferous critic of the British government's "meanness" towards the arts, including the evershrinking funding of galleries and the introduction of admission charges.
"I am fed up by the way everything is decided by accountants," Sir Denis said this week.
"It is not too late to change my plans. All I have to do is leave a note to my trustees... and more of my paintings will go abroad after my death."
People in this country will be pleased to know that Sir Denis imposed no restrictions on the five paintings he donated to our own National Gallery.
Perhaps this has something to do with his family links with Ireland. His mother, Lady Alice Evelyn Browne, the daughter of the 5th Marquess of Sligo, was born at Westport House in Co Mayo.
His father was John FitzGerald Mahon, a baronet and a member of the Guinness Mahon merchant banking clan.
Despite the financial background of his family Sir Denis chose not to go into banking. According to a friend, "he never had the problem of working: he was born with a silver spoon in his mouth."
The silver spoon allowed him to pursue a career as a gentleman scholar and collector of objets d'arte. After attending Eton and Christ Church College, Oxford, Sir Denis turned his attentions to the study and appreciation of European painting.
He was a disciple of the Austrian refugee, Nikolaus Pevsner, at the respected Courtauld Institute in London.
Pevsner was responsible for steering his interest towards Francesco Barbieri, more commonly known as Guercino, "the squint eyed". Guercino's works, and those of other 17th century Bolognese painters, had fallen into a certain disrepute since the middle of the 19th century and were considered over large and florid by some.
As a student, Sir Denis began to collect Gucrcino's drawings, which were so inexpensive at that time that it was cheaper to buy an original drawing than a photograph of a painting. The drawings now form part of his bequest to the Ashmolean Museum in Oxford.
In Paris in the 1930s he bought his first painting by Guercino, the enormous Jacob Blessing the Sons of Joseph, from a dealer near the Louvre. He fell completely in love with the beautiful, sumptuous, fleshy paintings of Guercino and those of his fellow Bolognese Baroque practitioners: Carracci, Guido Reni and Domenichino.
Throughout the next 35 years Sir Denis built up the largest private collection in the world of Italian Baroque paintings. And through his enthusiasm and dedication he almost singlehandedly brought a new respectability to this era in art.
He also collected works by Nicolas Poussin and others of the French classical tradition. He became known as the leading authority on 17th century Italian painting. His book Studies in Seicento Art and Theory, published in 1947, is accepted as the definitive reference work on the period.
He has written authoritative catalogue essays on many Baroque artists and has contributed countless articles to international art journals.
A slew of accolades and honours include the Medal or Ben Emeriti della Cultura presented by the president of Italy in 1957.
In 1964 he was elected an honorary academician of the Clementine Academy at Bologna. Other academies followed with further distinctions.
In Britain he received a CBE in 1967 and in 1986 he was knighted for his services to the arts.
Sir Denis stopped buying paintings during the late 1960s, when he felt that prices had become too silly. He never paid more than £2,000 for any one work, and he has said that his entire collection - now conservatively valued at £25 million - cost him just £50,000 to amass.
He was twice a trustee of Britain's National Gallery and he has been a regular visitor to the National Gallery of Ireland for decades.
Staff there regard him as a special friend and speak highly of his generosity, not just in the context of his recent bequest, but of his willingness to impart advice and expertise freely.
In 1993 he authenticated Caravaggio's The Taking of Christ which had been discovered by the gallery's senior curator, Sergio Benedetti. Sir Denis was just as thrilled as Mr Benedetti and later on, when he took part in an RTE documentary on the painting, he handed over his fee enthusiastically to the National Gallery.
As far back as the 1970s, when James White was the gallery director, Sir Denis mooted the idea of bestowing some of his collection. And the fact that one of the five donated works is Guercino's Jacob Blessing - the very first painting he ever bought - is seen as proof of his special regard for the gallery.
Sir Denis has no close living relatives: he never married and lived with his late mother for most of his life. He was very devoted to her, and upon her death in 1970 he became rather despondent, finding it difficult to look after the large house in Cadogan Square, Chelsea, which they shared.
He still lives in the house with his paintings, alone but not lonely. For, in the words of an Italian friend, "he is married with his art".