I think communication is one of the key tools to understanding. Here I would like to mention that when I say communication, I mean talking, yes, but also communication of a product via package, in the form of typed notes, music, poetry etc.
Talking to yourself is essential as it enables us to understand ourselves and thus, eventually help us make others understand us!
Alok says, "I am what I think." I kind of agree with it. The belief that your personality depends on your thoughts and view-point is very correct. But this phrase is incomplete.
Your thoughts make you, true. But till you express them, your thoughts serve no purpose.
Einstein wouldn't have made the brilliant contributions to science if he didn't believe in his thoughts and work to eventually make all his findings. But also, he wouldn't have been what he is today if he wouldn't know the art to express his work and make others understand the same.
This is what makes teaching a very difficult profession.
This is what makes more communicative doctors more popular.
This is what helps depressed people to come out of their trauma.
This is what enables us to understand any form of music.
This is what makes sure we fall in love.
This is what provides an outlet to all our thoughts.
This is what completes me.
Prolly this is why my blog-name is express. Another more practical reason is, "express" is the first reaction I get when I introduce myself to people :P