Blink is about rapid cognition, the kind of thinking that happens in the first two seconds when you encounter a situation.  These instant conclusions can be both powerful and accurate.  Gladwell points out that the conclusions we reach in those first two seconds can be just as worthwhile as the conclusions we reach after collecting extensive information.  He discusses a phrase from psychology, the power of "thin slicing."  Thin slicing says that we are able to make sense out of situations based on the thinnest slices of experience.  In the book's first example, he tells the story of Thomas Hoving, former curator of the Metropolitan Museum of Art.  Hoving has dedicated his lifetime to studying ancient Greek art.  One day, the curator of the Getty Museum showed him a statue they had purchased for $10 million. 

Hoving took one look at the statue and immediately said, "It's fake."  In a split second, the statue had struck him as "wrong."  After an extensive study of the statue by other experts, they agreed - the statue was a fake.  It took the other experts more than a year to reach the same conclusion Hoving reached in a split second.  Why was he able to reach that decision in the blink of an eye?  When you spend a lifetime studying something so closely, you're educating your subconscious.  You develop your instincts to such a fine edge that, in an instant, you can examine an unusual situation and instantly know what it means.