The delicate task, choosing a successor in Benedict's shadow

Call it the "chill effect."

When the College of Cardinals gathers in the Sistine Chapel under the splendour of Michelangelo's frescoes,its memberswill be dealing with a spectre. The well and certain knowledge that the last pope is still alive, and living just down the road.

The cardinals in conclave will be acutely aware that they are electing not only a new pope, but through him, a direction for the church. And whatever their choice, it will be read as a reflection on the papacy of Benedict XVI.

Of course, the cardinals are free to choose whomever they wish, and Pope Emeritus Benedict XVI has already pledged "unconditional reverence and obedience" to his successor.

But and it's a big but with the former pope still alive, will the cardinals be willing to elect someone who wants to make substantial change?

To do so could be seen as critique of Benedict's leadership. In a church not exactly known for its public self-criticism, and with little or no tradition of rebuking the decisions of former leaders, a very delicate situation has arisen.

The election of John Paul II in 1978 brought a tidal wave of charisma into the papacy. After the very short reign of John Paul I, John Paul II took the role of pope onto the global stage and became a major player in geopolitical events.

Through his writings and speeches, he created a profound vision, which was a church fully engaged with the world and throwing its weight around on the global stage.

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It was a controversial vision, to be sure, but over the course of the next 25 years, John Paul II put his stamp on nearly every aspect of the church.

The enforcer

With his death in 2005, the cardinals chose as his successor Joseph Ratzinger, whose influence in John Paul II's Church is hard to overestimate.

Cardinal Ratzinger was in many ways the enforcer of John Paul II's vision. After his own election as pope, Benedict XVI's eight years were very much a continuation of John Paul II's church, albeit with a few tweaks here and there.

When a pope dies, there is a very definite end to a pontificate. The period of mourning can itself become transformative, generating an expectation of rebirth and change.

Historically, this has not always occurred, but the opportunity is there. While the legacy of the former pope is always respected, no one has to worry about his feelings.

Benedict XVI's resignation has created an unprecedented situation.

On the streets of Rome, this is being described as a "hinge moment" in the history of the church. (The word "cardinal" itself comes from the Latin "cardus," meaning "hinge.")

For more than a generation, the church has been on a very particular path. Now, there is a palpable sense of expectancy, anxiety, even urgency over its future. Which way the cardinals' hinge will swing has people here on tenterhooks.

Transformation?

Consciously or subconsciously, it may be difficult for many cardinals to bring themselves to vote for profound transformation, for fear it could be seen as a rebuke of Benedict XVI's vision.

Radical or immediate change would be problematic, in terms of graciousness and loyalty to the former pope to whom a great number of the cardinals owe their appointment.

While there are suggestions of anger within some parts of the Vatican's curial government over the pope's managerial leadership, it's unlikely anyone would wish to cause him personal embarrassment.

Yet the failure of the conclave to indicate some change in vision and understanding of the evolution of global affairs could make the Vatican hierarchy look moribund, and will certainly lead to dissatisfaction amongst some in the church, and many outside.

Cardinals themselves have a vested interest in maintaining the respectability of the office of pope and the smooth continuance of Catholic teaching.

Substantial change could be read as tacit acknowledgement of failed leadership, and that the church has been outmoded, which could undermine its moral authority amongst the faithful, we well as its legitimacy in global affairs.

Expect that upcoming events will be spoken of as "building upon Benedict's legacy"; a transition, not a break. When the new pope is elected, the Vatican will need to smooth over any disparity between the priorities of the new pope and those of his predecessor.

Those hoping for big, immediate change should temper their expectations. Still, new popes can surprise.

With the election of John XXIII in 1958, the cardinals were expecting a rather dull pontificate. What they got was Vatican II reform on a massive scale. But John XXIII didn't have to contend with his predecessor living next door.