Bridget Riley, National Gallery

    Forget the term op art — Bridget Riley is at home in the National Gallery, deep in dialogue with the old masters she reveres

    There is no such thing as an art movement with a really good and appropriate name. All such appellations are crude or misleading. For me, the worst is postimpressionism, which tells you nothing about anything and manages to exaggerate the deeply misleading initial impression of impressionism, which was nothing of the sort. Fauvism is also disastrous. It comes from the French for wild beasts and therefore suggests there is something of the wild beast about Matisse’s way of painting. Which is a joke. The third worst, in my opinion, was op art. Yuck. Not only are the sounds involved as grunty as a punch in a Jean-Claude van Damme movie, the information conveyed by them is so misleading. Particularly when applied to the queen of op art, its best-known practitioner and most sensitive explorer, the treasurable, transcendental and downright saintly Bridget Riley.

    Riley is not an op artist. She is — and this is where the semantics grow immediately impassable, and where I happily admit to instant defeat — a rhythmic expressionist, a colour poet, a master of essence art, or essentialist, a minimal emotionalist, but not an emotional minimalist. Or she’s just bloody good at what she does, a national treasure and one of the most intelligent and thoughtful painters now at work in the land.

    Op art is a reduction of “optical art”, and, alongside its grunty curtness, the chief problem with the expression is that it is so Neanderthalishly shallow. All art is op art on its most basic level. Even the lovely sound installation by Susan Phillipz in this year’s Turner Prize show, which consists of an empty gallery where you can hear the sound of Phillipz singing plaintively, depends for much of its impact on the mood-striking emptiness of the room.

    Riley’s work, however, has never been a reduction of anything to anything else. It has always been an enlargement, a conveyance of bigger understandings about the way great art is put together. It is thoroughly misleading, as well, to suggest that her pictures are aimed squarely and solely at the eyes. No art — not even Vasarely’s — does that. These are subtle emotional whisperings that employ colours and rhythms to trigger lingering memories in the viewer’s eyes and flutter them past their associated emotions. Calling it op art is like describing the forthcoming wedding of Prince William Arthur Philip Louis of Wales to Catherine Elizabeth Middleton as “W bangs K”.

    Proof of all this and more is provided by a very pleasing show devoted to Riley that has come to the National Gallery. No, that is misleading too: this exhibition has not come to the National Gallery, it has come home to the National Gallery.

    One of the main points the show makes is that Riley’s art, however abstract it may initially appear, has always been rooted in the art of the old masters. They, and not the science lab or the optician’s chart, are her first and best teachers. In a delightful return of favours, she is now teaching us important things about them.

    The show has an exceptionally wide time span. Pertinent paintings from the National’s collection, going back to Mantegna and Raphael, have been included alongside Riley’s work, which ranges from examples made at the beginning of her career to brand-new things produced in the past few weeks. Riley is now 79, so that is a mighty rainbow. A lesser artist would have resorted to smudging and vaguery to squash such a timescale into the National’s tiny Sunley suite. Riley makes a virtue of compactness and succeeds not only in making these petite galleries look grand and substantial for once (which is where a profound knowledge of op-art magic really is useful), but in creating a precise encapsulation of her chief artistic concerns. Just as her paintings find the deeper order in a visual cacophony, so this show finds the deep-seated order in her long and undu­lating career.

    We begin with a marvellous face-off: Mantegna on one wall, Riley on the other. The Mantegna — The Introduction of the Cult of Cybele at Rome, from 1505 — is a difficult painting that I shamefully admit to hurrying past on most NG visits. It’s difficult because all the figures we see in the procession carrying the new cult idol into Rome are painted a monochrome grey, as if carved from stone. Mantegna has tried to make it look like a sculpted frieze. The subject matter, too, is obscure. Only now do I learn that the cult of Cybele was an unusually bloody religion whose priests castrated themselves at their initiation, and whose followers had to cut themselves while worshipping. Mantegna describes none of these horrors, but manages to imply all of them with a careful selection of frozen grimaces and a wave of physical anxiety that ripples along the length of the procession like the Mexican wave at a football match.

    This is the aspect of the painting Riley has picked up on in Arrest 3, an arrangement of rippling lines that she painted in 1965, and which now engages the Mantegna in a fascinating tag contest across the ages. To echo the monochrome of Mantegna’s mock statuary, Riley has narrowed her palette to greys, blue-greys and blacks, which undulate in lines across the surface like the wake from a passing barge. The anxiety Mantegna implies with his frozen grimaces, and which you initially assume to be missing in the gentler Riley, reasserts itself when you reread her title: Arrest 3. The essence of Mantegna has been extracted and preserved in abstraction.

    The show ahead turns out to be as much about the old masters as it is about Riley. Her insights into their colorific ambitions and compositional plans, carefully presented in captions that she herself composed, are unusually helpful. Notably her careful description of what’s actually going on in the colour scheme of Raphael’s Saint Catherine of Alexandria. It’s the gallery’s most gorgeous Raphael, whose beauty is unmissable. Riley, however, notices how handsomely the handsome Raphael has tied the blue of the sky to the warm yellows of the earth with a cunning corkscrew of matching colours that twists up through St Catherine’s robes. It’s a brilliant bit of observation that takes your understanding of the painting onto another plane.

    All this constitutes the show’s amuse-bouche. The main meal is a range of pictures from various points in Riley’s career, with the lessons to which she has just drawn your attention in the art of others followed up in her own art.

    Thus, Raphael’s spiralling St Catherine composition finds a clever echo in Red with Red, from 2007, in which two types of red twist up through a background of blue that also forms a foreground. The spirals reappear in quadruplicate in a recent work called Blue (La Réserve), in which Riley creates a single sunny French landscape out of four upright interweavings of blue, brown, green and lilac. It’s as lovely a painting as she’s ever made.

    The display also shows off two new works painted directly onto the walls of the gallery. The largest of these, Composition with Circles 7, occupies the longest Sunley wall and is the chief reason this show feels so grand and big. If you had blindfolded me before I came in here and asked me how high I thought the Sunley Room was, I would have answered 20ft, maximum. Exhibitions in here always feel low and crowded. In fact, it turns out to be a whopping 45ft high, and Riley’s new wall piece, made entirely of interlocking black circles, stacked in ranks from floor to ceiling, is the first exhibit in living memory that makes the Sunley Room soar.

    This isn’t just veteran picture-making experience that is being displayed here. This is a particularly bright and insightful form of visual intelligence. Throughout the show, Riley takes the lessons learnt from her beloved old masters at the National Gallery and employs them in ridiculously clever new ways. Seurat, whose Bathers at Asnières is one of the gallery’s greatest masterpieces, is another of her favourites. The second giant wall painting here, Arcadia 1, has a similar colour scheme to the Bathers, with pale blues, warm browns and cloudy whites evoking the Seurat combination of river, riverbank and sky. But because this is a wall painting, with no frame around it, Arcadia 1 has a boundlessness about it that brings the entire room into play and turns every visitor into a potential Bather.

    As if all this were not enough already, the National Portrait Gallery, next door, has a small display devoted to the portrait drawings Riley made in her college days at Goldsmiths. They are superb. Working mostly in red chalk, and searching always for the dreamy essentials of a face, Riley does what Seurat did before her and masters drawing first. Apparently, she spent three years studying the faces of her fellow students, over and over again. Only after she was really good at figure drawing did she fully know she was fully ready for abstraction.