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In the last of a three-part series, writer and philosopher Roger Scruton tries to define the elements which make a great work of art.

The world of art, I have suggested, is full of fakes. Fake originality, fake emotion and the fake expertise of the critics - these are all around us and in such abundance that we hardly know where to look for the real thing. Or perhaps there is no real thing? Perhaps the world of art is just one vast pretence, in which we all take part since, after all, there is no real cost to it, except to those like Charles Saatchi, rich enough to splash out on junk? Perhaps anything is art if someone says that it is. "It's all a matter of taste," they say. But is there nothing to be said in reply? Do we have no way of distinguishing true from false art, or saying why art matters and how? I shall make a few positive suggestions.

First, however, we must ignore the factors that distort our judgment. Paintings and sculptures can be owned, bought and sold. Hence there is a vast market in them, and whether or not they have a value, they certainly have a price. Oscar Wilde defined the cynic as the one who knows the price of everything and the value of nothing. And the art market is inevitably run by cynics. Utter trash accumulates in our museums largely because it has a price tag. You cannot own a symphony or a novel in the way you can own a Damien Hirst. As a result there are far fewer fake symphonies or fake novels than there are fake works of visual art.

Image copyright Getty Images

Things are distorted too by the channels of official patronage. The Arts Council exists to subsidise those artists, writers and musicians whose work is important. But how do bureaucrats decide that something is important? The culture tells them that a work is important if it is original, and the proof that a work is original is that the public doesn't like it. Besides, if the public did like it, why would it need a subsidy? Official patronage therefore inevitably favours works that are arcane, excruciating or meaningless over those that have real and lasting appeal.

Find out more Roger Scruton is a writer and philosopher

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So what is the source of that appeal, and how do we judge that a work of art possesses it? Three words summarise my answer - beauty, form and redemption.

For many artists and critics, beauty is a discredited idea. It denotes the saccharine sylvan scenes and cheesy melodies that appealed to Granny. The modernist message, that art must show life as it is, suggests to many people that, if you aim for beauty, you will end up with kitsch. This is a mistake, however. Kitsch tells you how nice you are. It offers easy feelings on the cheap. Beauty tells you to stop thinking about yourself, and to wake up to the world of others. It says: "Look at this, listen to this, study this - for here is something more important than you." Kitsch is a means to cheap emotion. Beauty is an end in itself. We reach beauty through setting our interests aside and letting the world dawn on us. There are many ways of doing this, but art is undeniably the most important, since it presents us with the image of human life - our own life and all that life means to us - and asks us to look on it directly, not for what we can take from it but for what we can give to it. Through beauty, art cleans the world of our self-obsession.

Our human need for beauty is not something that we could lack and still be fulfilled as people. It is a need arising from our moral nature. We can wander through this world, alienated, resentful, full of suspicion and distrust. Or we can find our home here, coming to rest in harmony with others and with ourselves. And the experience of beauty guides us along this second path. It tells us that we are at home in the world, that the world is already ordered in our perceptions as a place fit for the lives of beings like us. That is what we see in Corot's landscapes, Cezanne's apples, or Van Gogh's unlaced boots.

Image copyright Getty Images Image caption Petites Maisons Villageoises Avec Une Vieille Femme Et Une Petite Fille by Camille Corot

This brings me to my second important word - form. The true work of art is not beautiful in the way an animal, a flower or a stretch of countryside is beautiful. It is a consciously created thing, in which the human need for form triumphs over the randomness of objects. Our lives are fragmented and distracted - things start up in our feelings without finding their completion. Very little is revealed to us in such a way that its significance can be fully understood. In art, however, we create a realm of the imagination, in which each beginning finds its end, and each fragment is part of a meaningful whole. The subject of a Bach fugue seems to develop of its own accord, filling musical space and moving logically towards closure. But it is not an exercise in mathematics. Every theme in Bach is pregnant with emotion, moving with the rhythm of the listener's inner life. Bach is taking you into an imagined space, and presenting you, in that space, with the image of your own fulfilment. Likewise Rembrandt will take the flesh tints on an ageing face and show how each one captures something of the life within, so that the formal harmony of the colours conveys the completeness and unity of the person. In Rembrandt we see integrated character in a disintegrating body. And we are moved to reverence.

Image copyright Getty Images Image caption Rembrandt's Self-portrait With Two Circles at the National Gallery, London

Formal perfection cannot be achieved without knowledge, discipline and attention to detail. People are slowly beginning to understand this. The illusion that art flows out of us, and that the only purpose of an art school is to teach us how to open the taps, is no longer believable. Gone are the days when you can make a stir by wrapping a building in polystyrene like Christo or sitting in silence at a piano for four minutes and 33 seconds like John Cage. To be really modern, you must create works of art that take modern life, in all its disconnectedness, and bring it to fullness and resolution, as Philip Larkin did in his great poem "The Whitsun Weddings". It is fine for a composer to lard his pieces with dissonant sounds and cluster chords like Harrison Birtwistle, but if he knows nothing of harmony and counterpoint the result will be random noise, not music. It is fine for a painter to splash paint around like Jackson Pollock, but the real knowledge of colour comes through studying the natural world, and finding our own emotions mirrored in the secret tints of things, as Cezanne found peace and comfort in a dish of apples.

In art, beauty has to be won and the work is harder as the surrounding idiocy grows

If we look at the true apostles of beauty in our time - I think of composers like Henri Dutilleux and James Macmillan, of painters like David Inshaw and John Wonnacott, of poets like Ruth Padel and Charles Tomlinson, of prose writers like Italo Calvino and Georges Perec - we are immediately struck by the immense hard work, the studious isolation, and the attention to detail which have characterised their craft. In art, beauty has to be won and the work is harder as the surrounding idiocy grows. But the task is worth it, and this brings me to my third important word - redemption.

In the face of sorrow, imperfection and the fleetingness of our affections and joys, we ask ourselves: "Why?" We need reassurance. We look to art for the proof that life in this world is meaningful and that suffering is not the pointless thing that it so often appears to be, but the necessary part of a larger and redeeming whole. Tragedies show us the triumph of dignity over destruction and compassion over despair. In a way that will always be mysterious, they endow suffering with a formal completion and thereby restore the moral equilibrium. The tragic hero is completed through his fate. His death is a sacrifice, and this sacrifice renews the world.

Image copyright PA Image caption The Badminton Game by David Inshaw

Tragedy reminds us that beauty is a redemptive presence in our lives. It is the face of love, shining in the midst of desolation. We should not be surprised that many of the most beautiful works of modern art have emerged in reaction to hatred and cruelty. The poems of Akhmatova, the writings of Pasternak, the music of Shostakovitch - such works shone a light in the totalitarian darkness, and showed love in the midst of destruction. Something similar could be said of Eliot's Four Quartets, of Britten's War Requiem, of Matisse's chapel at Vence.

Poetry mentioned here

"They watched the landscape, sitting side by side/ - An Odeon went past, a cooling tower,/ And someone running up to bowl - and none/ Thought of the others they would never meet/ Or how their lives would all contain this hour." (from The Whitsun Weddings by Philip Larkin)

"Footfalls echo in the memory/ Down the passage which we did not take/ Towards the door we never opened/ Into the rose-garden. My words echo/ Thus, in your mind." (from Burnt Norton - part one of Four Quartets by TS Eliot)

Modernism arose because artists, writers and musicians held on to the vision of beauty as a redemptive presence in our lives. And that is the difference between the real work of art and the fake. Real art is a work of love. Fake art is a work of deception.

Image copyright ALAMY Image caption Matisse's chapel at Vence

A Point of View is usually broadcast on Fridays on Radio 4 at 20:50 BST and repeated Sundays, 08:50 BST - or catch up on BBC iPlayer

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