“He was a mystery to unravel, a puzzle I desperately wanted to solve.”

“She is the mystery that is wrapped tightly around the man I am trying so desperately to unravel.”

“Every mystery ever solved had been a puzzle from the dawn of the human species right up until someone solved it.”

“Man is a mystery. It needs to be unravelled, and if you spend your whole life unravelling it, don't say that you've wasted time. I am studying that mystery because I want to be a human being.”

“But the other half of my motivation came from farther back in my brain, in the curious part that I inherited. It came from the spot in my skull that feels the burning need to unravel puzzles, finish crosswords, indulge in Internet games, and read all the mystery books I can get my grubby little paws on. Like it or not, need it or not, and want it or not, I can't leave a good mystery alone.”

“The monkeys solved the puzzle simply because they found it gratifying to solve puzzles. They enjoyed it. The joy of the task was its own reward.”