The science of Indian music is founded on a most natural basis. Sound is graduated into tones, semitones, and microtones. Time is divided into six finer divisions, besides the usual six. Each note has its color, a planet, and an element, according to the mysticism of sound. Our music is based upon the principle of ragas, scales. Mystically they are subject to time and season, and each raga has an effect upon the spheres. Poetically ragas have their images; they are also idealized as "ragas" (men), "raginis" (women), "putras" (sons), "bharjas" (daughters). Mathematically they have increased from one to innumerable ragas. Artistically they are taken from the natural music of diverse people. And scientifically they have five divisions: ragas of seven notes, six notes, five notes, even notes, and odd notes.