A single, if complex, theoretical conclusion emerged from the first four chapters of this essay. It is that agents do well only if and when they act to satisfy only those desires whose objects they have good reason to desire, that only agents who are sound and effective practical reasoners so act, that such agents must be disposed to act as the virtues require, and that such agents will be directed in their actions toward the achievement of their final end. This sounds like a complex platitude, until it is spelled out. But these are not four independent sets of conditions that agents must satisfy if they are to act rightly and well. Spell out any one of them adequately and in so doing you will also have to spell out the other three. Moreover, like all theoretical conclusions in politics and ethics, this one can be understood adequately only by attention to the detail of particular cases that in significant ways exemplify it, not imaginary examples, but real examples. Understanding such conclusions is inseparable from knowing how they find application. Yet such examples will be of agents who are, like the rest of us, not yet fully rational, who are still learning how to act rightly and well, and who therefore are more or less imperfect in all four respects. That they are so makes it possible for them on occasion to serve another purpose, that of exhibiting the relevance of the generalizations of theory to reflection by particular agents on the singularities of their own lives. And this is of peculiar interest when those agents are ones from whom we ourselves need to learn.
The four individuals whose stories I am going to recount, at least in part, were just such agents. Each had a singular history, yet one that throws light on other lives lived out in in very different circumstances. For each there is an adequate record of the relevant episodes in their history. All four are neither too close to us that our view of them is distorted by our own concerns, nor too distant that the relationship of their lives to ours is problematic.