“Practical wisdom,” Aristotle told us, “is the combination of moral will and moral skill.” A wise person knows when and how to make the exception to every rule, as the janitors knew when to ignore the job duties in the service of other objectives. A wise person knows how to improvise,as Luke did when he re-washed the floor. Real-world problems are often ambiguous and ill-defined and the context is always changing. A wise person is like a jazz musician — using the notes on the page, but dancing around them, inventing combinations that are appropriate for the situation and the people at hand. A wise person knows how to use these moral skills in the service of the right aims. To serve other people, not to manipulate other people. And finally, perhaps most important, a wise person is made, not born. Wisdom depends on experience, and not just any experience. You need the time to get to know the people that you’re serving. You need permission to be allowed to improvise, try new things, occasionally to fail and to learn from your failures. And you need to be mentored by wise teachers.”