A friend recently introduced me to the writing of Michael Gerber, and here I find, courtesy of Dane Carlson, an article by Gerber on what makes an entrepreneur. Money quote (lots more in the article):
It’s my position that all successful entrepreneurs possess one fundamental ability, one fundamental quality, one fundamental skill, one fundamental interest, without which they would never be successful: Entrepreneurs possess the ability to perceive the world as a system. Without a doubt, every entrepreneur worth his or her salt is a "systems thinker." They could not do what they do without it.