 The executive virtues are an important ingredient in human excellence, but, like all virtues, they should not be cultivated in isolation from the substantive ones. When Aristotle discussed the virtues, he argued for the importance of phronesis or practical wisdom in the application of the virtues so that they would not be deficient, excessive, or misplaced. In the fully virtuous person, the virtues were never meant to be possessed in isolation but as an integrated cluster—one of the things the ancients were plausibly getting at when they spoke of the unity of the virtues.