In Dan Pink's talk about "The Puzzle of Motivation", he notes that there is a "mismatchbetween what science knows and what business does", particularly in the sense that business relies overly much on extrinsically rewarding people (usually with money) in order to motivate them. Do you agree that too much of a focus on extrinsic, monetary rewards can be problematic, and fail to keep people motivated over an extended period of time? In your own experience, what have you found more motivating at work (or in school)? The extrinsic reward of a pay raise (or the extrinsic reward of a good grade) or the intrinsic reward of mastering a task or problem and adding to your skills and knowledge? Do you think that your emphasis on an extrinsic or intrinsic reward might depend upon the situation you were in?