Subjectivity of the human mind

An article I read the other day informed me that medical research has only been able to get to the bottom of 13% of the human brain! Even though I had no way of confirming its authenticity it did ring a bell.
In economics there is a popular assumption which has been used in countless theories, i.e. that man is rational. New research has suggested that every human is rational in his own way. This means that rationality is also a subjective term, its different for you and me.
We all learn our moral values in school. Those values, in the innocent, ignorant childhood seem to be divine and supreme. There is also that belief and fear that there is someone, somewhere called God who punishes the bad and rewards the good. But, as we grow older we form our own beliefs and thoughts. The morals are straightened and bent as the individual wishes.
I feel that there is no right and no wrong for adults. For children, yes there is absolute right and absolute wrong but not adults. For adults there is only relative right and relative wrong. The relativity can also be stretched to the convenience of right or wrong.
Adults can think, reason and come up with the weirdest of scenarios about them being right or wrong. They can come up with bizarre justifications. The entire judiciary is based on that. What appears in black and white to even a child is invariably grey to the judge. Isn't that the reason why Kasab is still alive?
The complexity of the co-existence of us humans perplexes me. We have so many people and so many minds and thus so many opinions. Agreeing with your family is also an issue. How do we agree with so many others who we meet everyday? Or even agree enough to peacefully co-exist? Well do we?