On my first visit to the Art Institute's exhibition of Claude Monet's 1890s "series" paintings, two teenage girls stood looking at one of the pictures, a particularly radiant sunset landscape. One remarked to the other, "Oh, wow, I didn't even know they had colors like that back then." While at first amused by her ignorance, I soon had to conclude that in a certain important sense she had got it right. However much she did not know about such great 16th-century colorists as Grünewald and Titian, her eyes were seeing exactly what Monet had placed on his canvases: colors that can only inspire wonder.

Art historian Paul Hayes Tucker, in his excellent and informative catalog, stresses that Monet chose his subjects with a deep awareness of their significance. Grain stacks represent the fertility of the French soil; Rouen Cathedral is — as an example of Gothic architecture — a symbol of the great achievements of French civilization; poplar trees were used as symbols of the French republic from its inception. Tucker makes many good points, and provides often-fascinating background material, but it seems clear to this viewer that Monet's principal subject is light. Skeins of small brush strokes combine a variety of colors to render meadows, mountains, grain stacks, and cathedrals as a part of — indeed as creations of — the sun, the air, the sky.

Hanging at right angles to each other in a corner are two paintings of Norway's Mount Kolsaas, one of which is unfinished. A comparison of the two, which are quite similar compositionally, gives a good indication of where these paintings' magic dwells. While the unfinished picture is immediately pleasing, one needs to turn to the finished image to find a surface swarming with tiny details, each possessed of an ineffable delicacy, and each related to the others in a kind of organic interdependence that calls to mind the completeness of a living being.

It is because this work lives in such details that the paintings' deepest beauty does not survive in reproductions; the work must be seen up close, slowly, canvas by canvas. Viewed this way, the surface of each painting suggests a wealth of inner movement, as the eye progresses from one tiny colored splotch or line to the next, as if viewing some mysterious microscopic living world. This was certainly noticed, in some form, by contemporary observers; the critic Brownell wrote in 1895, "Monet's art [has] become nature itself."

In the 1890s Monet devoted most of his time to painting the same subject, again and again, often from the exact same position — but in different kinds of light, and in different seasons. These works were first exhibited together as each group was completed, and many of Monet's admirers at the time hoped — as Monet himself did — that some of the series could be kept together, preferably in France. Instead they were sold to collectors all over the world, a dispersion that evokes the breaking up and scattering of the panels of so many Renaissance altarpieces. Monet's series works were never exhibited together again in quantity until this show — only one of the reasons the show should not be missed.

When one sees ten or more pictures of the same grain stacks or cathedral exhibited side by side in the same room, one obviously notices the central subject. But because the subject is repeated in tends to recede, allowing the viewer to concentrate on what differs from picture to picture; it is in this way that light assumes its place as Monet's transcendent subject.

That light is a subject is also clear from the way each picture is painted. The facade of Rouen Cathedral is not presented as a solid mass of stone, but as a mottled and multicolored surface, crawling with brush strokes. The facade thus has the indistinctness of an object seen through a dense but richly colored haze. Indeed, it is one of Monet's great achievements that he can make the air, and the light that resides in that air, as fully visible as the world of solid things.

In one particularly beautiful series, "Mornings on the Seine," we see the transition from dawn to daylight in mostly identical compositions. In the dawn pictures, Monet's surfaces, while still richly detailed, are less mottled with different colors, as he creates in each area of color the unearthly, tenuous, shadowy unreality of things seen long before sunrise. As the light grows brighter, the colors grow more solidly sensual — yet they never take on the flatness of colors used only for their own sensuality, which so often characterizes bad painting. In the extremes of this series one can find a less obvious duality. Each area of color is painted with a richness that seems to radiate light out from the canvas, as if the work had light sources within it. At the same time each color has a delicacy so fine that one often has the feeling of looking through it, or even of passing through the surface and into the color as easily as one can pass through the air.

Monet's touch and vision are intensely physical. In his pictures of the Creuse Valley the hilly terrain is painted with a roughness that suggests some of the feeling of feet climbing on and stumbling against a rocky hillside. The colors and brush strokes in many of the grain-stacks paintings have a sensuality so strong that one feels the light can almost be touched. In addition to evoking movement, most of these works also suggest touch, smell, even taste. Among the five senses only sound is absent from these images, which are largely devoid of human presence.

Yet there is much more than sensual pleasure here. As is the case with a number of other 19th- and early 20th-century paintings, each work presents itself as a knot of paradoxes. The feel of the physical world — the reality of its objects and of the air that gives us all life — is present with stunning immediacy. But at the same time one cannot resist the feeling that each of these works is as carefully arranged, composed, and synthetically created as the gardens Monet cultivated at his home in Giverny. The overall compositions are often very simple, yet they seem carefully selected and perfectly balanced — too perfect to be an accident of nature. Similarly, the small streaks of color always give one the feeling they were selected as much for their harmoniousness in relation to each other as for their fidelity to the actual scene. The catalog recounts a wonderful story about how Monet, finding that a tree that he was in the process of painting was budding earlier than expected, set an assistant to work pulling off its leaves until he could finish his picture.

Another related paradox can be found in the work of a number of Monet's contemporaries, particularly Cézanne. The viewer is always encouraged to see each image as both a representation of an intensely felt nature and as pure paint. Thus Monet's brush strokes are always visible, and in many works he applies the paint in varying degrees of thickness to produce relief effects. This slight three-dimensionality heightens one's sense of the physicality of the object depicted, while making it even more apparent that one is viewing pigment.

Thus the natural and the arranged, the inner and the outer, the image as representation and the image as a sign of its own nature and making, the picture as window and the picture as abstract surface, are all possibilities present in each work. The viewer is asked not to choose one or the other, but to become more deeply aware of each alternative, of each contradiction.

The paradox that interests me most, and that seems most particular to Monet, is the oscillation between luminosity and transparency. In many of the sunset scenes the red light of evening seems to glow from deep within the image, yet if one changes one's perceptual perspective only slightly — steps back from or closer to the surface — this light can also appear to be no more solid than the invitingly placid surface of the water in the Seine paintings. The light, suddenly and inexplicably emptied of its physicality, becomes a window on some mystical, spiritual realm that lies beyond all possible imagery.

Of course each viewer will experience these works a bit differently. But I believe that the key to feeling their full power is not only to look at each painting slowly and with care, but to look at each from varying positions. They should be seen from three or four feet away to observe the entire composition; from a foot or less to dwell on details; and from perhaps the center of the room to allow simultaneous comparisons of the pictures in a series. In the Art Institute's superb installation, adjacent paintings constantly interact, as if in dialogue with each other, as if each had something to tell us about the other. Part of what they have to tell us of course is that the light and air are an integral part of our planet and of all that we see. But another part, harder to pin down with words, has to do with the way these pictures become something quite different from the nice, soothing, decorative scenes that make up the popular image of "impressionism." As one varies one's position in relation to a particular painting and observes how radically the work's effects change, one realizes that Monet has created images that go beyond simply rewarding careful viewing — as most fine paintings do — by revealing new details or aspects from each new position. Rather these works, individually and even more strongly when seen together, manage to escape from the realm of painting as object.

For many, paintings are a form of decoration, to be taken in at a glance, seen for whatever pleasing effects they may offer, but whose existence is always fundamentally separate from the viewer's. Monet's work breaks down such a separation. The multiple and contradictory possibilities that each work evokes make it more of an environment than a separate object. One does not look at it — one is in the experience of viewing it, one lives it.

In the next to last room of the exhibit there are some pictures of Norman cliffs, including one of Val-Saint-Nicolas in which the right and center are filled with cliffs, while some distant boats are seen on the sea at bottom left. In the left center, just off the cliffs, is a flock of birds. On each of my visits this painting struck me as odd, but it was a while before I understood why: the birds evoke movement by the fact that we expect that if we see birds in the air they are likely moving. By contrast, every other picture in this show evokes movement in unexpected places: in the fabric of a grain stack, the texture of a field, the placid surface of a river. These pictures evoke movement solely through Monet's painterly skill. In so doing, they suggest the life that inheres in all things, as well as new ways of seeing those things. This is something Monet had to struggle to achieve himself in order to also make it possible for us. While engaged in the Rouen Cathedral series, he wrote, "Each day I add and subtract something that I had not even known how to see before."

Professor Tucker explicates the social and political meanings Monet's subjects might have had for him and his contemporaries, surely a useful art-historical enterprise. Keeping in mind that one of the most enduring characteristics of great art is the way it can sustain reinterpretations by each new age, I would ask: What might these paintings mean for us?

We live in a culture cluttered with objects, with a surfeit of media noise and a glut of images that encourage only the most superficial visual impressions. If seen with care, Monet's work can help inspire a renewed vision. Rather than offering us wall decorations whose effects never change, he offers us pictures that have some of the completeness, complexity, and changeability of a living being. In fact, each canvas presents an integrated vision of naturally interdependent parts — trees, water, air, and sky; or sky, river, and the cliffs the river helped shape — painted with a pattern of tiny brush strokes that strike the eye as themselves complexly interdependent. To a species whose perception of all else on our planet is nothing if not hierarchical he offers images that envision all parts of the world, from trees to rocks to the polluted smoke over London, as equally alive. To a civilization whose hypertrophied industrialization is steadily breaking down all the life-producing interconnections nature built up over millions of years he offers an image of birds, boats, cliffs, sky, air, and light as all part of the same ecosystem. Indeed, it would not be going too far to say that these works offer a genuinely ecological vision. Connections are made between cause and effect, nurturer and nurtured — Tucker points out, for example, that the houses in back of the grain stacks were occupied by the farmers who grew and stacked the grain we see. But each painting also offers us a more complete experience of our own selves, as one feels one's perceptions of it shift between possibilities. And relationships between pictures in the same series heighten our awareness of the changing effects of light and air, of the natural cycles of the times of day, or the four seasons. Finally, this work is ecological not only in its vision of a unified natural world but also in its form — and in the kind of thinking that form encourages. The viewer is constantly led to widen his frame of reference: from objects in a picture to the relation between objects; from objects to their relation to light and air; from one half of a paradox to its antithesis; from a single picture's instant of time to the times that came before and after, which are suggested both within each painting in the way light effects are rendered and by the paintings of the same view hanging on either side.

Many have noticed in the Rouen Cathedral series an apparent conflict between Monet's multicolored, variegated surface and the Gothic solidity of the cathedral stone. But behind this apparent conflict lurks a deeper ecological truth. In emphasizing light and air over the stability of the object, Monet has seen deeper into the core of things, to a truth that many ignore. The sun is the engine that drives our world, makes the seasons, warms the air, creates wind and rain and snow, and provides us with the light and heat that make life possible. Once the world is understood in this way, what is unusual is not Monet's emphasis on light but that so many other artists have chosen to place their greater faith in the independent solidity of the object world. For the same light and air and rain that the sun helps create, and the plants its energy helps spawn, will over many centuries break up stone — including the stone of cathedrals — turning it ultimately into dust or new soil. Monet, living in a France rich in ruins, must have seen many examples of crumbling stone. Depicting the breaking up of the solid stone facade by sun and air, Monet is establishing larger connections — uniting in the grandest of ways cause and its predictable ultimate effect. While we see a single day dawning in the Seine series and the four seasons in the grain stacks, we are looking simultaneously centuries into the past and centuries into the future in the cathedral series. While Tucker emphasizes Rouen Cathedral as a proud symbol of French civilization, I would argue that Monet's deeper truth is that the "ecosystem" of sun, air, and wind makes all things creatures of light and time. It is also true that the never-ending process of change, across hours and across millennia, will long outlast republics and civilizations, even French ones.

A renewal of eyesight, an awareness of paradox, an ability to see deeper into the nature of things, a profounder awareness of the interdependent relationships that tie all things together — what more can one ask from any art? Riding home on the el from one of my viewings of the show, I looked back at the distant Loop skyline. Gazing at those skyscrapers through miles of slightly hazy air, I could see a delicate beauty in the way that varieties of light and air determine the appearance and ultimately the very existence of all things. Not the least important aspect of this great exhibit is that it deepened in myriad ways my sense of what the world is, of what it means to be alive.