Art can help convey otherwise inexpressible ideas and emotions. On paper, canvas, and the stage, we are repeatedly confronted with images of ourselves and the world we live in - and we cannot help but respond to them.
By Dame Liz Forgan DBE, Chair, Arts Council
This article is based on a speech given at the Institute on 31 March 2011.
Earlier this year I witnessed an amazing scene in a scruffy little theatre way up the Kilburn High Road.
The Chief of the Defence Staff, Sir David Richards, was standing on the stage. In the audience were half the Ministry of Defence and a bunch of young men with very short hair cuts on a day out from Sandhurst.
Sir David moved to the front of the stage, peered across the lights and said: 'Ladies and Gentlemen. If I had seen this before I went to Afghanistan, I must tell you: I would have been a better commander.'
He was talking about The Great Game, an extraordinary series of plays about the history of Afghanistan from 1842 to 2001 that lasted all day and told a sobering tale of adventure, heroism, hope, idiocy and despair. Its sources ranged from the wonderful diaries of Lady Florientia Sale, a nineteenth-century General's wife, to the real or imagined lives of assorted squaddies, spies, jihadists, patriots and other players who have wandered over that unforgiving terrain in the past 150 years.
Sir David had roused half the Army - and later half the Pentagon - to see these plays not because they did not already have access to any amount of military intelligence, specialist history and textbooks, but because the art of theatre gave it a depth and subtlety of meaning which nothing else had conveyed.
And that, I want to suggest, is the power of art.
It is what human beings turn to at times of greatest intensity, and it allows forms of expression which are oblique, insidious, reaching through the senses of sight, hearing or touch to places where the intellect cannot penetrate.
A Testament to the Past and a Window to the Future
You may be familiar with the terrible battlefield landscapes of Paul Nash and the work of the World War I poets like Wilfred Owen and Siegfried Sassoon, who brought the realities of war home to the whole world. Sassoon's cold anger was all the more powerful for being cast in the simplest of verse forms.Â
         I know a simple soldier boy
         Who grinned at life in empty joy
         Slept soundly through the lonesome dark
         And whistled early with the larkÂ
         In winter trenches cowed and glum
         With cramps and lice and lack of rum
         He put a bullet through his brain
         No one spoke of him againÂ
         You smug-faced crowds with kindling eye
         Who cheer when soldier lads march by
         Sneak home and pray you'll never know
         The hell where youth and laughter go.
Soldiers know all about the power of art to motivate - patriotic songs, regimental marches and US army training chants all use rhythm and melody, whether it's A Long Long Way to Tipperary or Pomp and Circumstance. Â Victories get Tchaikowsky's 1812 Overture or Beethoven's Eroica. Defeat gets a Pibroch or a lament on the pipes. It's not all 'great art', but it all uses art's tools of sound, rhythm, colour and line to move human hearts.
Art speaks of pity, fear, courage and celebration in ways nothing else can do. Kings and commanders through the ages have made as much use of it for their purposes as Sassoon did for his.
And nothing else does grandeur quite like art. What does Henry VIII do when he wants to put two fingers up to the Pope? He commissions Holbein. How do the Stewarts demonstrate that it's their turn for the limelight? Van Dyke. But of course great artists like these don't do simple propaganda. You can tell a great deal more about both Tudors and Stewarts than either Henry or the Charleses ever meant you to by looking at their court portraits.
And it is not all kings and soldiers. Throughout human history some of the most important stories, and most potent expressions  of love, fear, fury or awe, have been told in art. Abstract or realist, music, colour, movement or image. Profound or simple. Universally understood or arcane. It's the language our culture talks when plain straight narrative isn't enough  to convey the power of raw emotion. It is the language through which we understand things which we may not wholly comprehend.
Tangible Effects, Eternal Themes
Art is everywhere. For everything. And every little of it is by what you might call 'artists'.
When our earliest ancestors wanted to describe their working lives, they scratched drawings of hunted animals on the limestone caves of Cresswell Crags. When Shostakovich wanted to pour out his sorrow and rage at the prison of the Soviet state, he wrote his Fifth Symphony. But Stalin, too, used a form of art for his idealised workers and peasants in that very same state, which to him represented a Socialist Utopia.
Diego Rivera conjured the Mexican Revolution in poster art. Catholics and Protestants drew their wars on the gables of Belfast and Derry.  Graffiti artists  spray cartoons and scribbles on dangerous walls to claim their territory. Hebridean islanders sing for loss, Spanish gypsies sing and dance for sex. Cypriot peasants model exquisite figurines of fertility gods. Papuan villagers create intricate patterns to decorate ceremonial masks. Inuit carve the seals and bears they live with out of whale tusks.
And professional, famous artists, though they may be considered to make better art, make it for the same reasons. Peiter Breugel painted terror of damnation. So did Michelangelo, Dante, and half the painters of the Middle Ages. Mark Wallinger set a little white figure of a naked man on a plinth in Trafalgar Square and called it Jesus. Behind him in his search to find what we mean by divinity stretches a countless host, from the great icon painters of fourth century to Francis Bacon. John Cage and Maurice Ravel - in their entirely different ways - turned sex into music. Death inspired the late quartets of Beethoven and fuelled the rage of Johnny Rotten.
We just cannot stop thinking about these things - love, death, God, eternity, meaning, identity, sorrow, fear - and we have to exchange these thoughts with other people, whether our contemporaries or human beings from the other end of the earth or centuries before or after our own times. That's the power of art.
And if you doubt this need - to express feelings and to respond to the power of line, shape, colour, sound and rhythm and words - just look at some of the many extraordinary examples of the power of art to heal and soothe the most troubled of spirits.
It started with Saul, who couldn't settle to anything until David came and played a psalm or two. But it certainly didn't stop there. Our prisons are full of people whose inability to express themselves - or who could not find a way of doing so within the confines of the law - has driven them to crime, and who only begin to reassert control over themselves as human beings when someone finds a means of expression they can use.
Glasgow gangland murderer Jimmy Boyle was utterly changed by learning to paint in the Special Unit in Barlinnie. He became a mentor and inspiration to generations of kids who may otherwise have followed him into a life of drugs and crime.
Dance United works with prisoners all over the UK, teaching them to move their bodies in ways which are beautiful and expressive and giving them a form of voice they have never had before.
I once heard a speech therapist play the tapes of his weekly sessions with an autistic kid so cut off from all human contact by his disability that he could only scream and snarl in feral sounds all day long. No one could speak to him or understand what he said. His frustration had turned him into a wild beast. The therapist just started to beat gently on the table at the pace of a human heartbeat. Days later the boy stopped screaming long enough to listen for a minute. Days later the therapist started beating in simple groups with a pause in between. Months later the boy echoed the rhythm of a group. The therapist responded with the same rhythm - and then for the first time in his existence that boy had communicated with another human being. Now it was certainly not the B Minor Mass. But it was rhythm and pattern and echo and communication. I call that art.
Art wrings your withers. It hits you in the solar plexus. It explains things nothing else can. It wriggles its way into your heart and soul just when your intellect thought it had everything nicely sorted. It produces the greatest joy and plumbs the deepest sadness. It is consolation and agitation. It explains and makes you think again. It is a tool of tyrants and a sword of truth.
Furthermore, the creative industries contribute about £60 billion to the British economy every year, slightly over 6% of GDP. And the government investment in the arts is the equivalent of about one pint of milk each per week.
If you're interested in that sort of thing.
Dame Liz Forgan DBE is the Chair of the Scott Trust, a board member of the Conservatoire for Dance and Drama, a non-executive board member of the Department for Culture, Media and Sport and a Trustee of the British Museum. She was Chair of the National Heritage Memorial Fund and the Heritage Lottery Fund between April 2001 and September 2008, and was appointed Chair of the Arts Council in February 2009.
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