All this does not mean that the East did not make any progress in material things, for if one takes for instance the science of medicine, the books of Avicenna have been the foundation of medical study for the whole world. Besides the music of the Vedas was not only music but a psychological expression of sound and rhythm; and therefore it was also a mystery, a science so perfectly formed that it was not only useful for worldly things, but for meditative purposes. In fact music became the most essential part of religious practice.