There is only one practice of solitude: to make a choice and carry it out well. The particulars assemble around this simple principle. One may later regret the choice; one may end up reversing or abandoning it. The choice may consist of doing nothing or refraining from a decision until the time is right. But no matter what it entails, one must entrust oneself to it in order to see it clearly. The practice of solitude requires education and experience. None of the choices of solitude can be made without insight, if they are to be made well. Many practices of solitude can be conveyed only through example. Teachers who practice their subjects--who think about them and work on them in their own time--can show students a way of life. They need not "model" for the students in any canned way; their very conduct is a model. When teachers read a poem aloud or present a mathematical proof, their tone conveys whether they have thought about it at length, played with it, argued about it, and more. Students will likewise learn from the teachers' handling of conflicts that arise in class and in school. But there is more to the practice of solitude than simply doing something well or working toward good performance. The person who shapes something is also shaped. People think of "character building" as something that takes place outside, in the world, but much of it happens in private. Reading, playing an instrument, memorizing the elements, all of this makes a person just a little different from before. Seeing the world a little differently, he is slightly altered in turn. All he needs to do is honor this new shape, not apologize for it, not slur its syllables. It is possible, even with abundant foibles, to live up to the way one sees the world. People learn, over time, what they will not and cannot do, what they will not and cannot give up. Sometimes the practice of solitude comes down to a simple "no." That "no" protects all sorts of other possibilities. It guards a life. (Contains 5 endnotes.)