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Andrew Motion: The Toll Gate, Rousseau

When Henri Rousseau died in 1910, at the age of 66, his daughter invited Robert Delaunay to paint a posthumous portrait of her father. "Please be so good as to depict him in his black morning coat, with an open waistcoat and black tie," she wrote. "That is to say, quite properly – not in the overalls that you were more used to seeing him in."

This sounds like a concession to bourgeois taste, which in a sense it is. But it's also proof of the ways in which Rousseau's life as an artist combined with his career as a servant of the government. Born in 1844, he worked as a customs official between 1871 and 1893, officiating first at a toll booth on the Auteuil Embankment, and later at the Porte de Vanves; he taught himself to paint as he raised duty on merchandise and foodstuffs taken in and out of Paris. In the last part of his life, when he painted full-time and was taken-up by avant-garde luminaries such as Gauguin and Picasso, he was known as "Le Douanier" – the customs man. Throughout all this time, he embraced the attractions of order and structure and regularity, while also feeling very strongly the allure of wild freedom.

This freedom is best shown in the famous jungle pictures, which combine the presentation of creaturely liberty with a display of unhindered imagination and psychological drama. No wonder the surrealists liked him. But it also appears in pictures that seem to be much more nearly tame. One of the best of these is his little masterpiece The Toll Gate (c1890), which possibly represents his workplace at the Porte de Vanves. It is a picture in which tradition combines with individual talent – and also disputes with it.

There are several stories of Rousseau using his worktime as painting-time. "He would find somewhere to sit alone, to paint and draw," one of his friends remembered. And there's evidence to show that much of what we see in The Toll Gate is accurately described: the gate itself, the bollards, the high bank of earth (fortifications), even the figure standing on top of them, all appear in a contemporary photograph of the Porte de Vanves. But there's plenty that's adapted or made up as well. The grassy area in the foreground of the picture, for instance, which is laid over real-life cobblestones, and the view beyond the gate? We'll probably never know for sure, but it seems reasonable to suppose the trees layering towards the skyline, and almost engulfing the factory with its two chimneys, and the church with its slim spire, are there under licence rather than in fact.

Prolific nature, calm-looking but rampant, lurks just beyond the gate. This is not the only way in which the picture makes us aware of boundaries. The crossing- (and meeting-) point of wild and tame, and country and city, is echoed by the structural difference between horizontals (a part of the X-like path which holds the whole picture together) and verticals (the trees, the gates, the figures, the chimneys). All these allow for the idea of tension within reconciliation, and make the picture feel at once dynamic and still, full and deserted, familiar and strange.

This mixture of opposites is matched by narrative ambiguities, and in particular the picture's human figures. Two of these have a clear role to perform: they're uniformed customs officials. But they're presented as little wind-up toys that have just popped out from a humanised cuckoo-clock. The third figure is even more oddly poised between one thing and another: hidden (cancelled) by the long leg of a lamp-post, it is not clear whether he (or she) is approaching the city or leaving it, and not clear either what is in the cart. A large, heavy object apparently. A chest of drawers? It matters, because without knowing, we can't be sure whether its owner will have to pay duty (or has just paid it).

The business of owing, which pervades The Toll Gate, helps to explain why so enjoyably crisp a picture should also feel so bounden. What do the figure and the cart tell us about Rousseau's relationship with the employer he was so quick to defend ("I'm a civil service man")? They comprise a classic image of displacement. They make us think of a refugee.

Margaret Drabble: Self-Portrait with Bandaged Ear, Van Gogh

Van Gogh with his bandaged ear stares with clear and unflinching blue eyes from the wall of the Courtauld Gallery with an expression of dignified and stoic endurance. Visitors pause and gaze, arrested by one of the best-known and most sombre self-portraits ever painted. He does not stare directly at himself or the viewer, but into some inner world of suffering and fortitude. He does not look as mad as in his flame-toned 1887 self-portrait with a straw hat, nor as ill as he did when he painted himself in 1888 as a Japanese ascetic in ashen colours against a pale green Veronese background, with sunken cheeks, receding close-cropped hair and a stubble beard. In the Courtauld portrait, painted in early 1889 not long after his quarrel with Gauguin and Gauguin's abrupt departure from Arles for Paris, he looks both determined and resigned – determined to continue to work, despite the "vast shipwreck of his life's esteems" (a phrase from John Clare, another tormented artist), and resigned, in my interpretation, to the inevitable recurrence of the bouts of intense mental suffering that threatened his reason and eventually took his life.

We know a good deal about Van Gogh's state of mind from his remarkable letters, where we can read in heart-breaking detail of the high hopes he had held of establishing an artists' colony in the south of France. Van Gogh had known years of intense isolation and loneliness, and he craved, perhaps too overtly, companionship. The optimistic spirit of The Yellow House survives in many colourful and joyful works, as do poignant paintings of the empty chairs of Gauguin and Van Gogh, representing the most intense period of their creative friendship. Dogged by money worries, and by differing attitudes to daily expenditure (again itemised in scrupulous detail to Vincent's patient brother Theo), the relationship was unlikely to survive, and a violent dénouement was perhaps inevitable, although the form it took continues to appal, move and astonish.

On the night of 23 December 1888 Van Gogh, as we believe, cut off part of his right ear, and took it to a prostitute in a brothel, an act of manic craziness that precipitated Gauguin's desertion. Recently it has been suggested that it was Gauguin who sliced off his friend's ear with one of his fencing swords in a brawl, or in self-defence, and in support of this theory it must be said that Gauguin repeatedly wrote to Van Gogh asking for his fencing gear to be returned to him, a request that Van Gogh found irritating and childish, though whether it had any sinister implications we do not know. Certain it is that Van Gogh made mock of the "engines of war" with which Gauguin had equipped himself. But whatever happened that night, the friendship was at an end, and Van Gogh was alone once more, confronting a future of mental instability, religious hallucinations, poverty and solitary labour. The fact that he knew his delusions to be delusions was little comfort to him. They would attack him just the same.

The self-portrait makes him look like an old soldier, wounded in battle. He will not sign off yet. His heavy buttoned greatcoat will see him through another campaign, and his hat of cheap and weirdly animated fur will keep his balding skull warm through another winter. His firm and handsome mouth conceals his broken and missing teeth. His bandaged ear will heal – indeed, within weeks he is joking about having a papier mâché substitute made. But it is a long road ahead, and he knows it. He foresees the asylum at St Rémy, the doctors and nuns, the fellow inmates (whom he ceases to regard as crazy once he gets to know them, and whom he paints with respectful affection).

Perhaps he foresees the astonishing work of his last few years – the cornfields, the cypresses, the irises, the olive groves, the starry skies. Perhaps he knows that his paintings will not sell in his lifetime. But he will work on, as miners and peasants work, because that is what he does. He saw himself as a labourer, and he laboured.

In the background of the portrait, on the wall, we see a tribute to his recent discovery of Japanese art. We also see an easel with a pale, unfinished canvas. The easel is at once a crucifix and a peasant's A-frame for the carrying of burdens. The canvas waits.

Ali Smith: The Etang des Soeurs, Osny, near Pontoise, Cézanne

Green. How can I be this old and still this green?

Imagine a picture, more than 100 years old, in an empty gallery, the floor buffed, the cleaners come and gone, the room locked and darkened. The light outside falls, then comes up again, the place opens its doors. It's the moment before the people come and go in front of it all over again the length of another day.

The story opens when I go to the gallery with you and we both see this painting at the same time. We both stop and stand quite still because the painting, which is all movement, is also about what still means.

It's a painting of a tree over water and some other trees and a path. But what it's really about, you say, is, is . . .

I look at you. I see you're flushed, you've coloured up. It was made really fast, you say. (You are speaking quite fast.) Look, it's not finished here, you say, and here, it's been done really quickly again with the flat of the knife. Uh huh, I know a little about Cézanne, I say, I know how when he was an old man in Aix the village boys used to follow him and throw stones at him; I mean, look how modern it is, it's 40 years ahead of itself. I say it like I know and like these things might be connected. You point out the reds and greys and umbers, the working of reflection, the flecks of green in the tree-trunks. You use a word I don't know and then you spell it: alizarin. You mention Giorgioni; I nod like I know (though I don't). You say some things about post-impressionists using opposite colours in shadow, often a hot colour so that shadow becomes light. I say something about light and dark, point out stripes and diagonals. You point to the centre of the picture, how there's a space held in what looks like the opposite of space, in the fullness and movement of the leaves and the wind, there, look. I say ponderously how lacking in ponderousness it is. You nod. Then you say this:

Look at the way the artifice of it is the thing that makes it alive. Look at the way it's made out of the flatness of its own surface so we'll know we're not being deceived, so you'll know that it's just a painting. It takes away illusion.

No illusion. That's it. The surface opens itself. What I'm looking at ups and arrows right through me like someone just shot me with colour, with the truth about green. It's like being mugged by life, punched in the gut by umber green, red green, gold green, brown green, grey green. Who knew that green was a present tense, that greenness could moss all the pasts and the futures, cover all the words that ever believed themselves carved in stone and eat them into air? The gallery falls away, leaves nothing but leaves and striplings in a landscape where the curve of the tree is the curve of the eye is the curve of the surface of the piece of gristle inside the chest that happens to be keeping me breathing. What just happened? I turn to see where I am, again. I'm here. You're still there still beside me. You turn and regard me back. Your face is as bare as mine.

Ruth Padel: Landscape with the Flight into Egypt, Pieter Bruegel the Elder

"Landscape with?" So what are we supposed to look at, the story or its setting?

This landscape is a dialogue between blue-green and brown, darkest at the bottom with a red scatter in the right-hand shadow, from flowers like droplets of blood whose almost unnoticeable scarlet is echoed in Mary's red robe. Behind her is a dead tree whose top has dropped, forming a cross with the trunk.

Landscape into narrative, the crucifixion foretold in a falling spruce.

Her donkey has passed a pollarded tree hung with a shrine like a nesting box, the kind Bruegel painted as Catholic rural shrines in haymaking. Out of this falls something else, an idol. In iconography of the flight, paganism collapses as Christ goes past. On one branch of it sits a sentinel black bird, marking the moment at which the family comes out of one shadow and enters another.

Only one face is visible. Mary's eyes are turned down; Joseph has his back to us, leading them into a chasm so dark it looks black. But something four-legged in there, a stag maybe, is looking up at them, and a white bird is flying through the dark. The painting is a little theatre of barely noticeable falling and flight, a dialogue between visible and veiled, movement and stillness.

The centre is a hidden baby, refugee from Herod's baby-massacre, and this is transition, the darkest part of their journey. Behind them are two facing shores for past and future, Holy Land and Egypt. In that mystic way in which New Testament shadows Old, the displaced family seeks asylum in the country from which Moses led his persecuted people. Both shores are light. The open water between narrows to a V into which Mary's figure rises as another V upside down.

It is hard to see in reproduction, but both shores hold towns. The ones they've come from are blueish; blurred, as if underwater. The towns they'll reach are sunlit and biscuit-coloured. But the only people visible are three travellers around a cave, the left-hand shadow, so far away they are the same size as that black bird. Bruegel will make the parallel between bird and human soul more obvious in his 1565 Winter Landscape with Skaters and Bird-Trap, where uncaught birds are the same size as people skating. His landscapes are allegory as well as narrative. The bird traps are set for human souls risking the world's slippery ice.

So what is a landscape? Greek tragedians displaced the moral pain of their day into myth. Bruegel explores his in two ways. In peasant allegories where landscape is absent, and in religious narrative moments whose landscape setting matters as much as the characters. Between 1562 when he painted Triumph of Death and 1568 when the Netherlands finally rose against Spanish rule, he perfected landscape as the place of suffering.

This one, from 1563, expresses his own experience of displacement. About 1552, age 27, he went to Italy where he did his earliest signed, dated painting, Landscape with Christ and the Apostles at the Sea of Tiberias. His earliest surviving works are drawings. This man from the Low Countries produced drawings which connoisseurs call unparalleled in European art for mountain grandeur.

Back in Antwerp, he began the peasant themes which gave him his nickname, "Peasant Bruegel". His mother-in-law came from the town of Mechelen, whose artists suggested to him the moralising, peasant themes by which he expressed obliquely the horrors of reformation and Spanish occupation. As Auden said, the 1562 Landscape with the Fall of Icarus is "about suffering". Landscape is where important moments happen. A Procession to Calvary (1564). A moment on a donkey in the mountains. Ayslum-seeking.

Amit Chaudhuri: La Loge, Renoir

Pierre-Auguste Renoir was never my favourite impressionist. I studied him as a teenager for the same reason I studied the post-impressionists and late Turner: for the release they constituted from the overripe representational quality of renaissance art. My teenage soul in Bombay rejoiced at no longer having to gaze at nudes that purportedly looked like real, flawless naked women, at Venuses and Davids that closely resembled, right down to the tendon, the real Venus and David, at dead pheasants that glowed like actual dead pheasants in a gentleman's kitchen. "Human kind cannot bear very much reality," wrote TS Eliot; and he might well have been writing of a certain revulsion against the renaissance. Part of my antipathy must have come from what I saw as my cultural inheritance. Whatever was "Indian" in me couldn't recognise the pheasants and reclining nudes. This didn't prevent me from participating, intimately, in Van Gogh's fields, in Cézanne's hillsides, in the elements that combined to produce Turner's mysterious steam engine. Like the cities of the world from the end of the 19th century onwards – London, Paris, Berlin, Calcutta, Cairo – the new painting was a place of frenetic cultural intermingling which we could all, in various identities and guises, inhabit.

With Renoir, Europe still seemed very distant. An Indian contemporary of Monet's or Alfred Sisley's might have encountered, in Bengal, some of the very things they did: a semi-industrial sunset; an elusive vantage-point glimpsed at the end of a canal in the middle of a city. Sisley's and Monet's pictures contain a new awareness of the momentary in the midst of the everyday that's also in evidence, soon after, in Tagore's songs and the works of the poets and artists who follow him. But that Indian would have probably seen the sort of people gathered at the Moulin de la Galette in Renoir's famous picture of a café only in a colonial setting.

The crowd in the cafe and on the square almost provoke, unfairly, the question you might legitimately ask yourself when you watch the film Notting Hill: "Where are the immigrants?" You don't ask this of the Sisley painting because the intercultural contact that's characteristic of modernity's abandon – bringing together styles from the Parisian street, Bali, Japan, Africa and India – has already begun to animate its technique. You turn to Renoir's cafe expecting that abandon and play. But you're disappointed. The painting has none of the air of estrangement of, for instance, Van Gogh's cafés. Instead, it's a painstaking, penetrating study of a frozen society, fixed by class, a bourgeoisie that, even while drinking and dancing outdoors, is unaware of anything but itself, and apparently unconscious of the conflicted world of imperial France it thrives in.

"All great civilisations have been based on loitering," said Renoir's film-maker son, Jean, in relation to his first experience of India. But it could also be a statement about Paris, and a certain response to Paris, of which impressionism, post-impressionism, the writings of Walter Benjamin, and some of Renoir's own films are examples. But it would be wrong to look in Pierre-Auguste's paintings for the flânerie you find in his son's work.

This came home to me when I saw, for the first time, the original of La Loge – with the painting described above, Renoir's most powerful meditation on the bourgeoisie. Unlike Sisley, Monet, Cézanne or Gauguin, Renoir isn't concerned with the outdoors, or the street, or the aura of unfamiliarity that's inherent in everyday locations in the modern world: he's fascinated by interiority – not the interiority of individuals, but of a class. It's a class intent upon studying, admiring, and spying upon itself from various angles, and, in doing so, in keeping at bay or denying the momentous change that surrounds, defines, and will superannuate it.

The theatre box is a sort of fragile social cocoon; the shared glance, even if it has a private, erotic charge, confirms the artificially inviolate and self-regarding nature of this world. Benjamin said, referring to the rise of the novel, that, by the 19th century, the public wanted to read about itself. The same could be said of theatre when La Loge was painted, with Ibsen's gradual pre-eminence. But the figures are not looking at the stage. They – as the painter knows – constitute the pulse and tissue of theatre itself.

In this way, Renoir inaugurates a line taken up by his son in La Règle du Jeu, the incisive dissection of the French bourgeoisie's relentless fashioning, and preservation, of its own universe.

Picture This at Somerset House – Writers' Talks in the Courtauld Gallery, is at Somerset House on 4 and 13 October, 6.30pm. www.somersethouse.org.uk