With the concentration of power in Rome, perhaps the responsibilities of the papacy are not simply too much for a person of Benedict's age, but for any one person.
Four contributors, all of whom wrote for a previous series called "What Next?" which reflected on the start of Benedict's papacy, now reflect on its conclusion.
The unique features of the modern papacy must be considered when analyzing Benedict's resignation -- including issues of collegiality, age, and secular power.