QUOTE(Rainbow @ Dec 23 2005, 04:36 PM)

Not necessarily, it might help you to be able to clap basic rhythms, for example, before you start playing the viola (an excellent choice of instrument btw, it shows good taste!) but it always helps to be able to apply the knowledge you learn to something practical. Remember, we're always here to help you.
Though if you are a complete beginner to music you might need help in understanding the idea of how different note values work in practice.. it doesn't make immediate sense to everyone who understands it theoretically.
Learning some basic theory before starting to play might help you to make sense of the music when you dp start to play.