Think about the metric by which your life will be judged, and make a resolution to live every day so that in the end, your life will be judged a success.

I've concluded that getting the categories right is an absolutely crucial step to building useful management theory, and unfortunately too few writers do this. You've got to engage in serious scholarship, and then figure out how to write it in a way that lots of people can understand.

In my first career I had founded my own company, with a group of MIT professors, before coming to Harvard to finish my doctorate, and so I had a deep respect for the brains, talent, and dedication of managers. That made it hard for me to believe the attributions in the business press that stupid management was to blame. So I looked elsewhere for an explanation.

The only useful information about the market will be what I create through expeditions into the market, through testing and probing, trial and error, by selling real products to real people who pay real money.

Every disruptive innovation is powered by a simplifying technology, and then the technology has to get embedded in a different kind of a business model. The first two decades of digital computing were characterized by the huge mainframe computers that filled a whole room, and they had to be operated by PhD Computer Scientists. It took the engineers at IBM about four years to design these mainframe computers because there were no rules. It was an intuitive art and just by trial and error and experimentation they would evolve to a computer that worked.

If the theory accurately predicts what they [scientists] see, it confirms that it's a good theory. If they see something that the theory didn't lead them to believe, that's what Thomas Kuhn calls an anomaly. The anomaly requires a revised theory - and you just keep going through the cycle, making a better theory.

Year after year after year, people write books about managing innovation or about leadership, for example, without ever going through the pain of saying, "This kind of leadership will cause this result in these circumstances and a very different result in those circumstances." This is academic malpractice of the worst kind.