The worlds of art and money have always been intertwined, and art collectors – from the dukes and popes of the Renaissance to the likes of Charles Saatchi today – have been important arbiters of artistic taste. While many works in private collections are bought in the glare of publicity and displayed in galleries, art and artefacts often disappear from view, adorning the walls of private homes or even put in storage as investments.

What is the role of modern day Medicis? Do they buy art as true aficionados or are they driven by commercial motives? If buying an artwork for investment purposes, even to mitigate against tax, helps fund a vibrant art market, keeps contemporary artists out of the garret and safeguards important artworks for posterity, does it matter if art is bought for non-artistic reasons? How do we assess their contribution to our understanding and valuing of art? Even if a collector is driven by purely private gain – financial or pleasure – might there be a public gain? After all, the end result of many a great collection is the creation of a museum or gallery wing. The nucleus of most of the world’s great museums, from the Hermitage in St Petersburg to the New York Met, began as private collections.

Nevertheless, some contend private art collectors who are indifferent to artistic worth artificially confer ‘great art’ status on unremarkable work. Might the huge sums of money distort public judgment about what constitutes ‘good’ art? Or, for all the fashionable disdain for big money, rich moguls and market-driven arts, is public funding of art any more reliable a guarantee of artistic excellence? However we judge art’s merit, in an era in which accessibility is a mantra, should great art be made available to all, regardless of ownership? Are some works of art so important that they belong to everyone?