Do you like music? And colour? Most of us respond to the simple pleasures to be had from light and sound, whether naturally occurring - the sight of a sunset and the song of a bird - or man-made - a familiar painting or a favourite song. Their sensations give a personal delight that creative people have always understood. Painting and music-making employ colour and sound as their basic tools, and an infinite variety of expressive results comes of these simple means - from the colours and forms of the visual arts and the pitches and rhythms of music. Some artists re-evaluate the way these elements are used; Schoenberg's music and the painting of Mondrian were achieved by stringent explorations of the basics. Such fresh approaches to colour or music can occasionally re-invent the art form, refigure the aesthetic landscape and cause ripples in the world at large.
The expressive powers of light and sound are not the sole province of the fine artist. Colour and music are often harnessed for more general purposes - they can, and have been used as means to the ends of religion, politics, commerce, recreation and therapy. The end-purposes will affect their creative use, sometimes suppressing all variation for the sake a uniform, recognisable product. A company, for instance, will specify particular colours to duplicate its logo; a national anthem sounds much the same, trills and all, each time it is played. The desired results are achieved by the proscriptive use of music and colour and artistic scope is circumscribed by the need for mechanical reproduction.
A more symbolic set of strictures are placed on the use of colour and music in the name of religious belief, even where the particulars of a conviction can seem a nonsense in hindsight. When Pope Gregory decreed the colours of the rainbow that Noah saw were red and green only, limners were obliged to decorate manuscripts accordingly. Likewise, the musical note B was long neglected because our ancestors' spiritual advisers considered it barely respectable. Contemporary attitudes are more relaxed: the choice of sound or colour is largely left to the discretion of the creator, as part of the individual's response to any cultural imperatives. Of course, there are circumstances where broader creative control is required. The integration of colour and music, within a film or a piece of theatre, sees their roles refined - sometimes to the point that their presence (or lack of it) is subliminal, subtly augmenting a text or underscoring a mood.
Attempts have been made to regulate the use of our senses even further, by stipulating relationships between colour and music themselves. Most often, arrangements of this kind serve the most exulted purposes, endeavouring to paint a picture of heaven with light and colour, and to describe it with musical notes. Perhaps the most pervasive doctrine of this kind emerged in the 17th century, when Sir Isaac Newton first analysed the coloured properties of sunlight. Newton felt obliged to divide the naturally-occurring spectrum into seven colours, one for each note of a musical scale. In this way, the phenomena of light and sound were united in the one mathematical matrix. His simple array has survived as a colour-music code, as well as a commonly-accepted way of describing the rainbow.