The role of the art collector came into sharp focus last week. It was announced that Simon Sainsbury, a scion of the supermarket family and a magnanimous philanthropist, had left an artistic bequest worth some £100 million to the nation. Important paintings by Monet and Bonnard, Balthus, Bacon and Freud will soon be joining the Tate and National Gallery collections. We will come to visit them. We will come to know and admire them as friends. But how much can we ever know about the man who amassed them? How much do we appreciate the collector’s art?

Sainsbury was famously private by inclination. He may not have been the spooky misfit of the lurid imagination. He may not have sat gloating in some gloomy back room over his great hoard of treasures. But he certainly seemed to have come from a tradition in which collecting was treated as a private hobby: an intellectual and emotional pleasure that served the additional function of decorating one’s private home.

Since the Second World War, however, a rather different strain of collectors has grown up. Their pastime has acquired a much more public dimension. They pursue their own passions — but with a growing awareness of wider responsibility. Their hoards are a matter of public record. Their finest pieces become globetrotting loans.

This is one of the significant changes that James Stourton, the chairman of Sotheby’s UK, notes in an intriguing new book that is published this week. In Great Collectors of Our Time, Stourton looks at art collecting in Europe and North America (with a glance at the Far East) in the postwar era. He invites us to explore the homes and the minds, the methods and museums, the fascinations and foundations, the skills and the legacies of some of the art world’s most extraordinary characters.

From the impenetrably taciturn Emil Bührle, through the immaculately educated Sir Denis Mahon, to the tattooed boffin Ted Power or the notoriously stingy Arthur Gilbert in his yellow tennis shorts, they make an exotic gallimaufry. There are as many types of collector as there are collections, we learn, as we tiptoe with the author through their Aladdin’s caves of priceless goodies, peeping and gazing, admiring and examining — and perhaps most importantly, gossiping — as we go.

So what makes a great collector?Money obviously helps. The world of collecting is dominated by a roll-call of grand dynastic names. It is a playground of tycoons. But cash alone, in this game, is far from sufficient. J. Paul Getty missed dozens of opportunities because he was mean, whereas the Menils, even though they were wealthy, were prepared to go into debt for something they really desired. And a handful of great collectors have started out with extraordinarily little. There are the Vogels, for instance, a childless couple who, meeting their living expenses with her librarian’s salary, spent his entire income as a post-office clerk amassing a spectacular collection of Minimalist pieces.

There is a strong tradition of dealers — Ernst Beyler, for example, or Eugene Thaw — who, like poachers turned gamekeepers, spend their trader’s profits on amassing a private hoard of treasures. And it certainly helps if, like Roland Penrose, you happen to have generous friends who are also artistic geniuses. He always called his collection “the collection that collected itself”.

To the discerning collector, knowledge is far more important than money. Mahon did not just have a banker father: he had a formidable art-historical education to boot. He knew more about Guercino, quipped Ben Nicholson, than anybody since Guercino. Expertise is definitely more important than cash when you are rifling for treasures in a Parisian fleamarket or rummaging around in some old curiosity shop. Besides “whether you buy a postage stamp or a Van Gogh, the pleasure to a collector is just the same,” declared Henri Schiller, who over the years has amassed one of the most magnificent libraries in the world. “I am by profession a collector,” he says. It is only his “hobby” to be an industrialist.

But knowledge is not everything either. “One can know too much and feel too little,” says George Ortiz, who claims to be entirely intuitive in his purchases. Certainly collecting involves passions and emotions. It speaks of instincts and obsessions. It may be an addiction harboured since childhood amid a world of marbles or fossils, stuffed birds or Superman comics.

It may be an interest acquired only with age: Michael Steinhardt had retired before he even started. It may be spawned by a single art work: Roger Thérond fell in love with a daguerreotype in a Paris shop window and from there went on to amass one of the finest photographic collections. Or it may be the offspring of a decorating project: Norton Simon, the formidable collector of Old Master paintings, was not even interested in art until he moved into a new home.

But slowly and surely the great collections take on a life of their own. Sometimes they have been shaped around a precise idea. Schiller’s, for instance, was themed around the whimsical fantasy that one day at the end of the 16th century Homer would return to this earth and want to learn about everything that had been happening and read all about it in the most perfect manuscripts. Other collectors are almost indiscriminate in their preferences. “I have no taste,” says Daniel Katz, “because I am interested in everything.”

Kenneth Clark once asked himself why men collect and decided that it was like asking why we fall in love — the reasons were as random and individual and various. But, at the heart of the great collection, there perhaps lies a hole: an absence which the process of collecting can work to fill. Was collecting a sex-substitute for Peggy Gugenheim? Did paintings stand in for friends for the deeply unpopular Simon? Walter Annenberg’s trophy acquisitions were like a family. They were his children, he said, and he wanted to see them every day. While for Nelson Rockefeller collecting was quite simply “the greatest recreation ever devised”.

Through their possessions these people appear to have discovered some fundamental sense of meaning. They seem to have found some way to express their individuality or satisfy their secret needs. Theirs were not collections to be treated merely like stock-market speculations or like fashions, acquired and discarded according to passing trends. They were pursued with the same sort of passion and energy, courage and dedication, discernment and sensitivity that the artists themselves put into their works.

This fundamental authenticity lies at the core of the art of collecting. Like the creator’s moment of vision, it can transform a mass of objects into something far more than the mere sum of its parts.

And, as the products of these many and various visions become increasingly public in our postwar era; when, for a start, thousands of art works are too big for display in our houses; and when even the biggest homes cannot house so much stuff, the collector starts to play an increasingly prominent role. He can give shape to our history. George Costakis, for instance, flying in the face of a thousand complexities to construct an unparalleled collection of Russian avant-garde works, pretty much defined the subject for those who now look back.

The collector can control the present, as in the case of Charles Saatchi, who created a market and an entire movement to fill it. And he can hold our greatest treasures in careful custodianship for our future.

A great collection, it seems, is in more than one sense, a gift.

— Great Collectors of Our Time: Art Collecting Since 1945 by James Stourton is published by Scala

The UK’s most important collectors

David Roberts
Millionaire property developer. Opened his space OneOneOne in Central London last month. Vast collection of more than 2,000 works, including pieces by Damien Hirst and Marc Quinn. Next year he launches the David Roberts Arts Foundation to benefit young curators and artists.

Anita Zabludowicz
Newcastle- born, buys a lot of work by young, unestablished artists. Recently opened a gallery, 176, in Chalk Farm, North London. Her collection is currently the focus of an exhibition at Baltic Centre for Contemporary Art in Gateshead.

Frank Cohen
The Manchester businessman’s collection comprises more than 1,500 contemporary works. He is said to have bought Tracey Emin’s work You Forgot To Kiss My Soul over the phone while having a curry.

Damien Hirst
Last year the Serpentine Gallery hosted an exhibition of works from the artist’s fine collection that included pieces by Banksy, Francis Bacon and Andy Warhol.

Charles Saatchi
Still one of our most important collectors, despite a certain amount of art world snobbery suggesting the contrary.

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