In the second place, the two-and three-part ‘Inventions,’ and the preludes and fugues in the ‘Well-Tempered Clavichord’ have proved themselves to be, as Bach himself hoped, the very best of teaching or practice pieces. It is not that your conventional Mr. Dry-as-dust teacher has power to inflict Bach upon every tender, rebellious generation. It is rather that the pieces themselves cannot be excelled as exercises, not only for the fingers but for the brain. One need not delve here into the matter of their musical beauty, but one must pause in amazement before their sturdiness, which can stand up, still resilient, under the ceaseless hammering of ten million sets of fingers. Clementi and Czerny are being pounded into insensibility; Cramer, despite the recommendations of Beethoven, is breathing his last; Moscheles, Dohler, Kalkbrenner, and a host of others are laid to rest. But here comes Bach bobbing up in our midst seeming to say: ‘Hit me! Hit me as hard as you like and still I’ll sing. And when you know me as well as I know you, you’ll know how to play the piano.’ So Bach has been, is, and will be introduced to young people. He inspires love, or hate, or fear--a triple claim to remembrance. In the third place, there is an intellectual complexity in his music which, as a triumph of human skill over the masses of sound, deserves and has won an altar with perpetual flame. And the marvel is that this skill is rarely used as an end in itself, but as a means of expressing very genuine and frank emotion. Here we come upon perhaps the great reason of Bach’s immortality--the warmth of his music. It is almost uniquely personal and subjective. In it he poured forth his whole soul with a lack of self-consciousness and a complete concentration. His was a powerful soul, always afire with enthusiasm; and his emotion seems to have clarified and crystallized his music as heat and pressure have made diamonds out of carbon.