3Most pianists know their scales, but few actually understand the essential principles of how they relate to each other. The Circle of Fifths is the ancient "Rosetta Stone" of music theory, that not only tells you which notes are in any key, but also contains the secret of how every scale is built and how scales relates to each other. In The Circle of Fifths for Piano, you will not only learn how "the Circle" works, you'll learn to build it yourself and gain instant access to the deep inner core of theory that governs everything in music.