Question

In this post, I will examine what exactly music is and how it might have evolved. Then I will proceed to explain why we find music enjoyable. This will naturally lead to the explanation of why most of us (if not all of us) find the major pentatonic scale and its derivatives to be naturally "happy". I will also be able to explain why, for instance, most of the popular chart-busters have simple rhythm patterns.

Sound

Men (and animals) have developed the capacity to hear for various purposes, one of the most important of them is to sense danger. For example, a hiding animal about to pounce and attack is detected by the man, who might be out of sight, using his ears -- the sound produced by the pouncing animal being the auditory cue. Likewise, rocks eroding and caving in (after perhaps some kind of land-slide) onto a man's house produces a series of sounds, which the man has to quickly perceive and react. Thus sound is mainly a cue for danger to which men have to react quickly to prolong their lives -- which is why men are highly receptive to sound. Let us examine the characteristics of sound that signifies danger. It is either a sudden short sound, as it is when an animal pounces or can be a series of sounds at random intervals and of random volume as it is when rocks are caving in.

First music -Rhythm

Now let us imagine that man A suddenly uses his hands and starts producing a periodic repeating sound. Man B (out of sight) upon hearing the first few sounds would sense danger initially and his body would ready itself to react to it (by producing appropriate hormones etc.). However, as man B continues to listen to it, he senses that there is something strange to this sound, in that, it is of uniform volume and is periodic; and it does not match any of the patterns of the sounds that indicate danger. Curious, he goes towards the source of the sound slowly and finds that it is actually man A generating it. Suddenly, the curiosity changes to relief and joy as he realises the safety in the situation. In other words, he experiences a series of emotions, namely fear-->curiosity-->joy, for what essentially constitutes the simple rhythm.

Why is it that the man B found the rhythm to be safe? Just because of the fact that the rhythm played consisted of sound at non-random times...In other words the pauses between the sounds bore simple ratios. This makes it highly unlikely that the sounds could have been produced by a natural cause; which in turn leads the man to a sense of safety and joy. Thus I claim that the simple periodic rhythm might have been the earliest music.

The different notes of music can be analyzed in a similar fashion. The different notes in music constitutes a simple ratios of the frequencies. For example if C (Sa) is 256 Hz, then G (P) is 3/2 of the original frequency which is 384 Hz. These simple ratios are those that make the probable source of the music non-random, which in turn causes emotions of safety and joy.

With this theory we are now in a position to explain several things which are empirically observed:

The pentatonic scale (or its variants) is common across various types of music -- for e.g. chinese music, Greek , Celtic, classical, Hungarian, and Indian music etc. I claim that it is common across most musical traditions because of the simplicity of the ratios of the notes in this scale. For e.g let us examine the notes of the major pentatonic scale (known as Mohanam or Bhupali in Indian music). The notes in this scale are: