His scheme of a new musical notation and the principles on which he defended it are worth attention, because some of the ideas are now accepted as the base of a well-known and growing system of musical instruction. The aim of the scheme, let us say to begin with, was at once practical and popular; to reduce the difficulty of learning music to the lowest possible point, and so to bring the most delightful of the arts within the reach of the largest possible number of people. Hence, although he maintains the fitness of his scheme for instrumental as well as vocal performances, it is clearly the latter which he has most at heart, evidently for the reason that this is the kind of music most accessible to the thousands, and it was always the thousands of whom Rousseau thought. This is the true distinction of music, it is for the people; and the best musical notation is that which best enables persons to sing at sight. The difficulty of the old notation had come practically before him as a teacher. The quantity of details which the pupil was forced to commit to memory before being able to sing from the open book, struck him then as the chief obstacle to anything like facility in performance, and without some of this facility he rightly felt that music must remain a luxury for the few. So genuine was his interest in the matter, that he was not very careful to fight for the originality of his own scheme. Our present musical signs, he said, are so imperfect and so inconvenient that it is no wonder that several persons have tried to re-cast or amend them; nor is it any wonder that some of them should have hit upon the same device in selecting the signs most natural and proper, such as numerical figures. As much, however, depends on the way of dealing with these figures, as with their adoption, and here he submitted that his own plan was as novel as it was advantageous.[326] Thus we have to bear in mind that Rousseau's scheme was above all things a practical device, contrived for making the teaching and the learning of musical elements an easier process.[327]