Little girl and the cookie jar experiment

I am reading an interesting book...called "Stumbling on Happiness". A lot of the information in the book is not new for me as much as it is from a new perspective. It has a very scientific feel!!! The book is trying to answer one central question...Why is it so difficult to accurately predict future happiness? We often find ourselves in the exact spot we imagined but without the feeling of happiness we imagined or a lesser degree than we imagined. To answer this question the author takes an indepth look at how our brains work or dont work when it comes to imagining the future. He explains the difficulty with abstract things like happiness. Happiness is highly subjective. It all depends on our interpertation, our interpertation, depends on our experiences and our experiences are as varied as lotto numbers. Not to mention we operate in a closed environment. What i mean by that is that my brain, my experiences, my imagination, my everything inside my head is closed off to everyone elses heads. I have been toying around with this idea for a while now in my own way. In my opnion this is the single greatest source of conflict among humans. We assume everyone sees the world the way we do!!! There is conflict when people dont see it my way and there is harmony when they do (but that only occurs in my mind) The unfairness is that others cannot know fully what i see in my world, and vise versa. By unfair i mean i cannot hold anyone to my world if they are unaware and i should not be held to someone elses either(again this is how i see it).
The book offers this simple example to illustrate the point (children are great guine pigs because they are so new to life). The experiment is with two little girls, both playing with toys in a room. There is a jar of cookies in the room. One of the little girls is taken out of the room. While she is away, the psycologist takes a cookie from the jar and hides it in the drawer. The little girl is brought back into the room. The girl that was in the room the whole time is asked does the other little girl know where the cookie is? She replied yes. She believed the other little girl had the same information she had dispite having not been in the room when the cookie transaction took place.
........to be continued