First of all, let us consider the question What is Music?, because before we answer why, we must understand what is it that we are actually talking about.
गीतं वाद्यं तथा नृत्यं त्रयं संगीतमुच्यते
— शार्ङ्गदेव, संगीतरत्नाकर
We find this definition by Śārṅgadeva in his Sangita-Ratnakara, where he says singing, instrumental (music) and dance, these three are called music.
Wikipedia says, Music is the arrangement of sound to create some combination of form, harmony, melody, rhythm, or otherwise expressive content.
Concise Oxford Dictionary says, music is the art of combining vocal or instrumental sounds (or both) to produce beauty of form, harmony, and expression of emotion.
But in a one of a kind definition, Sri Abhinavagupta says the musical sound is that which draws away to itself the minds of listeners from the non-musical, usual sound.
I like this definition. Because it hits at the core matter. And given the philosophical mind of Sri Abhinavagupta, we can expect that he will give such a definition.
But with this definition, a question arises, that why is it that this ‘musical’ sound has this ability to attract the listeners. Here, we must first understand that our five senses (Vision, Hearing, Smell, Taste and Touch) provide us either happiness or misery. And we always root for happiness, never for misery. So certain visions are liked because they provide happiness and those that provide misery are not liked. What is liked is desired and what is not liked is desired to keep away from. So, some sounds are liked because they give happiness. This is okay. But I feel the attraction part is still a bit unanswered here.
Therefore, we understand now that some ‘sense objects’ provide happiness and some provide misery. This is actually a fine scale of happiness from negative to zero to positive. Now the question why a certain sense object provides a certain index of happiness on this scale, this is difficult to answer. This maybe because there are some patterns in the universe, which we ourselves subconsciously are made up of, and when we come across such patterns from our senses, we like them. It’s a matter of order vs chaos.
This was a deeper discussion on what music is. But if you ask casually, we would be talking instead about the types of music prevalent in the world. We have different forms, genres or whatever you may call them. These different varieties come from different states of mind and likewise produce different states in the minds of the listeners.
So now, why music?
To be honest, it is quite self-evident. It is just there. How can we ignore it? We have so many languages to express our thoughts and emotions, and none of them comes close to the language of music. And it is universal. It requires no prior study to hear it, and experience it.
And in India, as other things, music has evolved to be expressed in a very subjective manner. There are rules, and then there are no rules. With an agreement to a ‘common ground’, then the musicians are free to roam in the clouds of imagination, or, invoke something higher and flow in that state.
Music can be for entertainment, and it is so in most cases. But when a person is in a state where he deeply longs for truth and meaning, such a person takes absolute refuge in music. And the result, as we can imagine, is quite different from the ‘entertainment music’.
This phenomenon has not been a rare case in India. In fact, there have been numerous ‘saint-musicians’. And so, the music, or the corpus of music literature, is already very spiritual or devotional. But this other kind of music, the longing one, the spiritual one, this is still a rarity in my opinion.
Therefore, it is hard to answer why music. It is akin to asking a saint why spirituality. There will be so much to say that they may end up staying silent.