Like every art form, music is linked to a particular time; it is the living expression of its own period and can be completely understood only by its contemporaries. Our 'understanding' of old music allows us only a glimpse of the spirit in which it is rooted. We see that music always reflects the spiritual and intellectual climate of its time. Its content can never surpass the human power of expression, and any gain on one side must be compensated by a corresponding loss on the other. In these essays, Nikolaus Harnoncourt summarizes his views arising from years devoted to the performance of early music. The problem of interpreting historical music is particularly critical in our age, when modern music has little appeal for the listening public. The vacuum left by the absence of a truly living contemporary music is therefore filled by older music. But for performers and audiences to understand music of earlier times, they must learn to comprehend the languages and messages of the past.