Professor Herdt describes some of why the virtues are so important in thinking about what constitutes a flourishing life. A challenging question concerns how to foster the virtues. Christian theologies of course offer accounts of transformation by the Spirit, by God’s love, by following Christ’s example, by suffering, etc.
Professor Herdt distinguishes between infused and what are sometimes called acquired virtues. With regard to the latter, there has been interesting work in psychology and the social sciences on interventions that can promote character development. Such interventions have been successfully evaluated in randomized trials with, for example, interventions to promote gratitude, forgiveness, and compassion. However, such "interventions" may be more difficult to conceive of for fostering the cardinal virtues (practical wisdom, justice, fortitude, and temperance). These may require longer term communities and commitments and formation. It would be interesting to understand what virtues and aspects of character can and cannot be fostered through simple interventions at the population level.
Empirical study of the virtues requires measurement which itself is challenging with respect to character. It would likewise be interesting to better understand what virtues are more, versus less, amenable to empirical assessment. I have discussed some of these issues and challenges in the pieces below:
VanderWeele, T.J. (2022). The importance, opportunities, and challenges of empirically assessing character for the promotion of flourishing. Journal of Education, 202:170–180.
VanderWeele, T.J. (2022). Character and Human Flourishing. Psychology Today, August 2021.