Don DeLillo's bleak short story "Looking at Meinhof" describes an encounter between two strangers at the Museum of Modern Art in New York. The meeting takes place in the room displaying October 18, 1977 (1988), Gerhard Richter's remarkable suite of 15 canvases ruminating on the alleged suicide/death/police murder of Andreas Baader and other members of the Baader-Meinhof terrorist gang in a German prison in 1977. The man in the story, it transpires, is killing time between job interviews. The woman, though, is in thrall to the cycle of paintings.
"I realise now that the first day I was only barely looking. I thought I was looking, but I was only getting a bare inkling of what's in these paintings. I'm only just starting to look ... I think I feel helpless. These paintings make me feel how helpless a person can be."
She has developed an obsession with the multiple images of Ulrike Meinhof dead in her cell ("the head, the neck, the rope burn, the hair ... the slurred mouth in one painting appearing nearly natural elsewhere"); the two paintings of Andreas Baader dead on the floor of his cell, head similarly in profile; the large slurred canvas of the crowds at the funeral, the three pale coffins hoisted on shoulders, passing through them.
She has taken to returning day after day to interrogate the "ashy blur" of the grey-toned paintings based on the found photographs in police files and tabloids, and to immerse herself in the wintry but apparently consoling light emanating from their surfaces, enjoying a transcendent experience of the kind Mark Rothko liked to report people had in front of his paintings, and that pilgrims still travel to the Matisse chapel in Vence, for example, or the Rothko chapel in Houston to share.
"The people who weep before my pictures," Rothko remarked, "are having the same religious experience I had when I painted them." That people cried when confronted with his pictures proved to him that he was communicating basic human emotions. "It was a cross. She saw it as a cross," DeLillo writes in "Looking at Meinhof", "and it made her feel, right or wrong, that there was an element of forgiveness in the picture, that the two men and the woman, terrorists ... were not beyond forgiveness."
Gerhard Richter is not a believer. In anything. "I believe in nothing" is the most famous thing he has said, his equivalent of Warhol's "I want to be a machine" and belief that "everybody should be like everybody". ("I want to be like everyone else, think what everyone else thinks, do what is being done anyway": Richter, "Notes", 1964.)
"I consider belief of every kind, from astrology to every elevated religion and all great ideologies, to be superfluous and mortally dangerous," Richter has said. "We no longer need such things. We ought to work out different strategies against misery and injustice, war and catastrophes."
Born in 1932 in Dresden, Richter was a child in Nazi-era Germany: his mother's brother, Uncle Rudi (whose portrait he later painted), died a young Nazi officer, while Richter's mentally disabled aunt was imprisoned in a Hitler euthanasia camp. He fled the eastern bloc and "the criminal 'idealism' of the Socialists" for Dusseldorf a few months before the Berlin wall went up in August 1961. Art, he once wrote, "has always been basically about agony, desperation and hopelessness". The art world, by contrast, "is entirely superficial. Openings, dealership, social game-playing: these have become the form of art. They have long since wholly or at least largely taken its place."
"Thirteen years under National Socialism. Sixteen years under East German Communism," reads his official biography. Followed, it might add, by nearly half a century of what Richter has many times (supposedly jokingly) called "Capitalist Realism" in the west.
Although the new paintings he is showing from next week at London's Serpentine Gallery grew out of the magisterial, geometrically patterned stained-glass window he designed for the south transept of Cologne cathedral, unveiled in August last year, the atmosphere Richter's paintings evoke is not one normally conducive to transporting the viewer to a spiritual realm.
He seems temperamentally better suited to the secure courthouse purpose-built for the trial of the Baader-Meinhof group in a field a few hundred yards from Stammheim prison in a suburb of Stuttgart in the mid-70s. The single-storey building was surrounded by high steel fences and floodlit at night, and armed policemen patrolled it with guard dogs. "Inside the windowless, artificially lit, technologically well-equipped, utilitarian and atmospherically space-age courtroom," Jillian Becker writes in her book Hitler's Children, "the prisoners sat in a row ... dressed in similar blue jeans and loose black sweaters, thin from their hunger strikes and with prison pallor on their faces." It is an emotional climate - wan, dejected, sinister and slightly cruel - reproduced in the work of a whole generation of younger European artists who might reasonably be thought of as Richter's children, pre-eminently Luc Tuymans, Marlene Dumas and Gregor Schneider.
Richter began doing social realism in East Germany; then, when he came to the west, was immediately taken up by the onslaught of pop art from America. This set him at odds with Georg Baselitz, his close contemporary and fellow fugitive from the GDR, who denounced and denied both mass culture and photography, which for many years formed the basis of Richter's art.
From the outset, Richter painted what his website describes as "images without glory"; images that rendered the ridiculous, ordinary; the tragic, ordinary; the beautiful, ordinary. "Many amateur photographs," he once said. "are more beautiful than a Cézanne."
Under the general heading "Photo paintings", click on any category - C includes Candles, Cars, Clouds, Corrugated Iron, Curtains; D begins with Death - and you are presented with images of insolent dumbness and puzzling neutrality. The subcategory "Everyday Life" brings up paintings called Pedestrians, Working in the Garden, Man on the Phone. Under "Buildings", we get Small Car Park, Small Church, Grey House, Corridor. Under "Household Icons", Kitchen Chair, Pillow Picture, Toilet Paper (many versions of the same, nearly used-up roll of prison-issue Izal).
It is almost as if, in these modest, mostly black-and-white paintings, Richter has stumbled across cheap images more or less accidentally and then spent a week or more translating them into paint. Which is roughly what happened. Throughout his career he has shown a distrust of intention. He has consistently refused the idea of the "masterpiece" or "inspiration", and preferred instead to rely on ready-mades and chance. The images in the paintings are almost without exception based on pictures torn from newspapers and magazines, or snaps taken with an inexpensive camera. They are further impoverished or distorted by being made to appear blurred or bleached or ham-fistedly under-exposed.
"I hate the dazzlement of skill," Richter wrote as a young man of 32, in 1964. "For example, being able to draw something freehand from life, or - even worse - inventing or putting together something entirely original: a particular form, a particular composition or an eccentric colour scheme ... I want to leave everything as it is. I therefore neither plan nor invent; I add nothing and omit nothing ... Being able to do something is never an adequate reason for doing it."
In the 1970s, in apparent contradiction of his younger self, Richter began to use colour ("Black-and-white was starting to get too aesthetic") and to turn his hand to abstract painting. But this was gestural abstraction in the manner of the abstract expressionists, with all the performative carpet-chewing and messy existential angst cleanly and clinically removed.
In his 2003 Mellon lectures, the former chief curator of painting at MoMA, Kirk Varnedoe, described Richter as "a part-time abstractionist" (a category in which he also placed Jasper Johns and Cy Twombly). Before the second world war, Varnedoe said, abstraction was an endpoint. It was something you arrived at after you had tried everything else. It was the absolute. For Richter, far from being an end-of-the-line distillation, abstract art was one option among many, to be picked up and put away again as he chose.
"Richter is not a painter of clarification," Varnedoe said, "but a painter of doubt, one who constantly lives with 'yes, but'. Like Warhol, he is involved simultaneously with representation and the nagging ghost of abstraction. But unlike Warhol, he works into abstraction from the inside, as an absolute abstract painter, and shuttles between a form of photographic realism and a form of abstraction." The pictures' "heartlessness about their mechanical nature" made them very difficult to love. There was "something acidulous and chilling" about Richter's colours. What his abstractions and his trademark blurry, photo-figurative paintings had in common was "the cool, deadpan, noncommittal nature of the engagement with the subject and the distance from the subject". So different from the old abstract expressionists' crusty ideals of sincerity and good faith.
Part of Richter's attraction for younger artists has been his refusal to accept that success means having a style. But Damien Hirst, a longtime admirer of Richter's, believes the "skin" of the pictures is what makes them identifiably "Richters"; that his work has always and only ever been about what Richter himself has called "the smooth, equalising surface". "The subject matter is secondary," Hirst says. "The unifying thing is the surface. The real care has gone into the surface of every painting. Photographs don't have a surface. It's what makes them different from paintings. It's what painting has left. It's like Richter takes a rippling, moving, delicate surface and hangs the image on top of it. It could have been rolled on in one sheet. They're like sweets or chocolate. They melt."
Hirst is an artist who owes a debt to the colour side of Richter's practice. He has always been happy to acknowledge this. In the mid-60s, Richter started making paintings which reproduced the kind of colour sample charts that can be picked up in any hardware shop. What he was interested in was their smooth perfection and the precision in the reproduction of the colours, with the minimum of composition. They were sober, impartial and anonymous.
Hirst saw reproductions of Richter's big, billboard-sized colour-chart paintings as a student, and many years later was prompted to adopt the same strategies of randomness, seriality and a gridded layout with his spot paintings, a raft of which was going under the hammer at Sotheby's as we spoke last Monday. Chatting about Richter was a kind of displacement activity. Richter's works also sell in the high millions. Hirst is far from alone in considering him to be among the world's greatest living painters.
Hirst has commented in the past that the spot paintings could be what art looks like viewed through an imaginary microscope: "A scientific approach to painting like the drug companies' scientific approach to life." Writing in the catalogue that accompanies 4900 Colours at the Serpentine, Birgit Pelzer remarks of Richter's work that "the painted colour charts attempted to be as far away as possible from the emotive and sublime, from expression and lyricism. They aimed to take art to the edge of its own destruction."
For several years, Richter painted the commercial colour cards as found, complete with white grid between the rectangles of colour, only on a grand scale. Sometime in the 70s he introduced chance and random selection into the composition; colours were numbered, and the numbers pulled out of a hat. Eventually, the separating margins were allowed to disappear, and raw colour freed to rub up against raw colour. The effect this produced unintentionally mimicked another photographic effect: that of pixelation - electronic blurring - except that digital hadn't been invented yet. "Bright, vulgar, modern colours," as David Batchelor has written, "in bright, vulgar, modern collisions with other bright, vulgar, modern colours."
In his book Chromophobia, Batchelor makes the distinction between what he calls "digital colour" (commercial paints that come out of a tin) and "analogical colour" (artists' paints that come out of a tube). "Analogical colour is a continuum, a seamless spectrum ... a merging of one colour into another. Digital colour is individuated; it comes in discrete units; there is no mergence or modulation; there are only boundaries, steps and edges."
The postwar period brought the digitalisation of colour in art. This, Batchelor argues persuasively, "was an entirely new conception of colour: more urban colours than the colours of nature. Artificial colours, city colours, industrial colours. Colours that are consistent with the images, materials and forms of an urban, industrial art."
In August 2007, the city of Cologne unveiled Richter's startling new window for the south transept of Cologne cathedral. The original window had been destroyed during the second world war and replaced with clear glazing in 1948. Nearly 60 years later, Richter elected to fill in the sections of Gothic tracery with thousands of gridded, vibrantly coloured squares which suggested that the early, stained-glass images of Magi and saints had been pushed through a processor to the point of hyperchromatic digital breakdown.
The seemingly arbitrary distribution of colours at Cologne was generated using a specially developed computer programme, and his renewed interest in using chance to determine composition led Richter to develop the idea for 4900 Colours at the Serpentine.
In this most recent work, acrylic chips are chosen at random, spray-painted, and glued to an aluminium sheet. "The random programme presents an instantaneous and apparently countless collection of coloured groupings," the catalogue explains, adopting the tones of a public-service announcement. "The computer executes instructions without conscience or discernment, without intuition or will, without feelings or inductive thought. We are in the finite and infinite universe of numbers where the calculation process is transformed into a production role." All human agency has been removed.
Why would a painter present a series of 49 identically sized, identically gridded panels made of industrially manufactured paint chips and present them as a single exhibition?
As long ago as 1966, Richter wrote: "I steer clear of definitions. I don't know what I want. I am inconsistent, noncommittal, passive; I like the indefinite, the boundless; I like continual uncertainty. Other qualities may be conducive to achievement, publicity, success; but they are all outworn - as outworn as ideologies, opinions, concepts and names for things."
He added: "Now that there are no priests or philosophers left, artists are the most important people in the world. This is the only thing that interests me."
· Gerhard Richter's 4900 Colours: Version II is at the Serpentine Gallery, London W2, from September 23 to November 16. Details: 020 7402 6075; serpentinegallery.org
· This article was amended on Tuesday September 23 2008. An editing slip meant we located the Rosary chapel, which Matisse designed and decorated, in Venice. It is in Vence, southern France. This has been corrected.
