The three-and-a-half-pound meat loaf between our ears is not a simple recording device but a remarkably smart computer that gathers information, makes shrewd judgments and even shrewder guesses, and offers us its best interpretation of the way things are.

Because those interpretations are usually so good, because they usually bear such a striking resemblance to the world as it is actually constituted, we do not realize that we are seeing an interpretation. Instead, we feel as though we are sitting comfortably inside our heads, looking out through the clear glass windshield of our eyes, watching the world as it truly is.

We tend to forget that our brains are talented forgers, weaving a tapestry of memory and perception whose detail is so compelling that its inauthenticity is rarely detected. In a sense, each of us is a counterfeiter who prints phony dollar bills and then happily accepts them for payment, unaware that he is both the perpetrator and victim of a well-orchestrated fraud.

Excerpt from Stumbling on Happiness by Daniel Gilbert