For the American jazz musician, Charlie Parker, it meant, "your own experience, your own thoughts, your wisdom."
"Without music life would be an error," said the German philosopher Friedrich Nietzsche.
And in the words of American pop singer Billy Joel, "Everyone loves music!"
They must be right, because we spend US$40 billion a year on music. But what do we mean by music? What defines it? And why are we so touched by it? The Big Question: What is music?
Music is something we can all take part in - says Professor Ian Cross, the Director of the Centre for Music and Science at the University of Cambridge. "Every single culture has music in one form or another. They may not have a word for music, but they often have a term which translates into music, singing and dancing."
Where does music come from? "Africa," believes Professor Cross. "We came out of Africa between 150,000 and 60,000 years ago and music came with us. As soon as modern humans got to Europe, one of the first things they do is leave not evidence of hunting, not evidence of fight for survival, but a proper musical instrument." The earliest known musical instrument dates back 36,000 years. It is a bone pipe found in Geissenklösterle in Southern Germany. Professor Cross says this suggests music was as significant for our ancestors as any other aspect of life.
"Music is something that you feel, that you bring to someone else through organising a set of sounds," says 18 year old Jeffrey Reid, a student in composition at the Royal College of Music in London.
So, how do you go about creating it? Jeffrey's teacher, Professor William Mival tells the Big Question that all traditional western music is the rearrangement of just 12 notes - arranged in harmony - the simultaneous sounding of notes of different pitches; melody - the sequence of notes that form the tune; and rhythm - the pulse or beat.
"There are many very eminent composers - people like Sir McCartney for instance - who do not know how to write music. He doesn't know how to read music," says Professor Mival. "There are huge numbers of people out there who do not have what one could call a traditional musical literacy, yet who are profoundly musical and who are able to create very exciting music."
So, what happens to our mind and body when we listen to music? Dr Nicola Dibben, who teaches music psychology at Sheffield University in the UK, says you can actually measure your emotional response to music with a heart-rate monitor.
Emma listens to some of her favourite music, Puccini's 'O Mio Babbino Caro', while Dr. Dibben monitors her response: "Your heart-rate was about 90 beats a minute. But at the moments when the singer's voice goes up to high notes, your heart-rate goes up to a maximum of 104 beats a minute…. Maybe that’s why music is so powerful, because we actually physically feel these feelings and that goes beyond words."
The ways we listen to music have changed significantly over the past century - from vinyl to cassettes to CDs, and now to digital players such as computers and portable MP3 players. Scott Cohen is the co-founder and vice president of The Orchard, a digital distributor of music worldwide. Before the 20th century, he says, to hear any music you actually had to see it live. The development of the first recording devices in the late 1880's allowed people to listen to music at their own leisure and in their own homes.
But it is not just about listening to your favourite tunes. "The greatest thing now is that the cost of recording has come down so much that almost anybody can afford to record their own music," says Scott. Take Pedro, a 21 year old Brazilian musician living in London. "Usually after a session I just record everything on my computer" he says. "It's been amazing to see how this young guy, making music in his room, suddenly has his music available worldwide."
So, what is the future of music? "There's going to be hundreds of different ways in which people get music. But one thing I'm sure of," says Scott, "is that everyone will be getting music digitally. It's not an "if", it is a "when" this will happen."
Have you ever wondered why certain tunes get stuck in your head? Professor James Kellaris from the University of Cincinnati calls these uninvited tunes "Earworms". He has identified three characteristics they all have in common: there’s usually an element of repetition - like in the theme from the film "Mission: Impossible", simplicity is a second characteristic - that's why children's tunes are more likely to stick with you than more complex material, and incongruity - when the tune offers you something unexpected, like the rhythm of the song "America" from West Side Story.
So, how do you get rid of earworms? "Some people report playing a game of tag with them; they sing the song that's haunting them in the hopes of passing it along to their colleague," suggests Professor Kellaris.
This edition of The Big Question was first broadcast on 25th December 2004
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