Music depends entirely on the sense of hearing, and this book is literally about how we hear it. During the past fifty years there have been spectacular advances in our knowledge of how the ear and hearing system work. In its advanced form it is a large, extremely complicated subject and really a closed book to all but specialists in that field of study. One can, however, extract a simplified explanation of the mechanism, to which basic musical phenomena can be applied. But add to that our modern understanding of evolution and behaviour, of how advanced animals including ourselves use their hearing, together with acoustics, and the mass of fact and belief about hearing music, and one is faced with a huge body of uncoordinated and sometimes conflicting material.

In such a situation in science, and it appears equally true of music, it is often fruitful to go back to first principles. So the book begins by discussing the origin and early evolution of simple ‘western’ tonal music, which appears to be almost universally accepted and acceptable. No one knows how music originated. I suggest that it started with experiments with artefacts – with instruments, and not with the human voice. This is not unfounded belief, for the later chapters appear to substantiate the assumption, and if it runs counter to your current belief, I ask you to give it the benefit of the doubt until you have read all the arguments.

A consideration of the evolution of simple music from first principles produces a list of basic questions about intervals and scales, tone, dynamic, harmony, time and so on. And as the discussion develops it leads amongst other things to the conclusion that the harmonics of musical sounds, which are the basis of so much theory about music, did not and cannot play the role which has been so widely attributed to them ever since they were revealed by Helmholtz in 1870. I then examine whether the hearing mechanism provides some form of answers to the questions and conclusions. I believe that it does and that it produces a different view of the basis of some fundamental features of music to those which are commonly held. It also provides a cogent explanation of why our hearing mechanism behaves as it does, and therefore why we receive the sensations of music in the form we do.