When my opera Plump Jack was performed in 1989 my first piano teacher sent me something that I'd composed when I was four. I remember I played it and it still sounded like me. I'm the same composer I was then.
It's not so much what you learn about Mumbai it's what you learn about yourself really. It's a funny old hippie thing but it's true as well. You find out a lot about yourself and your tolerance and about your inclusiveness.