the joy of music

It has been for quite sometime now that i was pondering over what makes most of us (leave alone those occasional loonies who literally hate music) enjoy music. What exactly is it a particular sound or a series of such sounds and silences possess that arrests attention ? I'm not referring to individual tastes in music but music as a whole entity. I was sure that this question must have been thought over by many people by now, if a guy is thinking about it 25 years after his advent to this wonderful planet as compared to music that has been there since ages. But then, I wanted to know, why i love it ... hmm .. self introspection .. not easy eh ? I tried and here are the some "answers" (clues .. rather ..) that i got:

1) Even when I was a kid, my parents seemed to be happy (smiling, nodding head and all other signs of happiness) whenever they were listening to music (carnatic and a few film songs). So i was already being told that "music" is nice and gives happiness. Ok. if not parents, someone else. Someone in our lives must have been noticed by us as being happy while listening to "music". Though I know that this definitely will have some influence on "liking music", I strongly feel that there are more scientifc reasons than mere imitation of someone else's seeming happiness. (how did the first guy ever get influenced ;-) )
2) It is not hard to realise that there are 7 major notes (err ... frequency-levels for puritans) that are common to all the sects of music irrespective of their geographic background. And they all sound exactly the same. I mean .. come on .. how can this be ?? Call it do-re-mi-so .... or sa-re-ga-ma .... they are all there .. as clear as daylight, staring at you, the seven of them. If the frequency levels that please a typical human ear are exactly same in various (sometimes unconnected civilizations) there's got to be something about it. There are some differences in the number of notes considered for music between these sects. For example even in Indian music, carnatic has 14 notes altogether in a set (including these major - basic 7) and hindustani has 12. Notwithstanding these differences, it's still a ponderable point that those basic 7 are the same. why .. why .. why ??
3) As most of the living creatures we care for, communicate using sound (need not always be in the audible range for human beings - i'm considering sharks, dolphins, bats and other earthmates which communicate in non-human audible frequencies), it is a natural thing, it seems, to respond to a particular variation in sounds as it might correspond (though not immediately perceivable) to a similar variation in sounds that we make while expressing some emotion. Even a non-exponent of music can easily relate to a emotion while listening to a piece. I feel it is that way, for the simple reason that our communication is based on sounds. How many times have we not said .... "hey that is a sad song .." even before we hear the lyrics ... ?
I guess it gives us some kind of satisfaction if hear something so akin to our communication and yet not in the immediate grasp. ... u know ... kind of satisfaction we get while we unwrap our gifts..... , if you get my drift. ....
4) What we perceive as "taste" of a particular food item is actually the summum-bonum of the looks of it on the plate, the smell we get while we eat and the actual responses of taste buds on the tongue. Similarly i feel that what we "enjoy" when we perceive music ... is not just the variation of sounds, but also the emotion associated with it, the imagery we associate .. (next time you hear your favourite song, try not to think of any images .... it was impossible for me ... ) with the emotion or the situation. For example, when i lend my ears to an orchestra ... my imagery is that of synchronization, blending .. ... errr .... conducting .. etc ... ; when i hear a carnatic piece, my imagery is in accordance with emotion i feel while listening to that piece and so on.

in order to get at the why of "enjoying music" i got to these clues .... let me see if further thinking leads me to a comprehensive answer that satisfies me.