Pope Francis held an audience Friday with the men who elected him, telling the College of Cardinals not to give way to "pessimism."
The 76-year-old pontiff also told the elderly cardinals who gathered in Vatican City's Clementine Hall to greet him that age is "the seat of the wisdom of life" which should be passed on to young people.
Before his formal installation as pope on Tuesday, Pope Francis, a native of Argentina and the world's first Latin American pope, is also expected to meet with journalists Saturday. On Sunday he will appear at the window of the papal apartment to recite the Angelus prayer with crowds of worshipers in St. Peter's Square below.
Meanwhile, the Vatican on Friday rejected as "defamatory" accusations that the newly-elected pontiff, the former Jorge Mario Bergoglio, did not do enough to oppose Argentina's 1976-1983 military dictatorship.
Among charges are that Bergoglio, who was the Jesuit leader in Argentina during that period, failed to protect two fellow Jesuit priests kidnapped and tortured by the junta.
One of the two priests says he later reconciled with Bergoglio. The other priest has since died.
Vatican spokesman Federico Lombardi said the accusations were part of a leftist "anti-clerical" campaign and must be rejected.
Pope Francis began his first full day as leader of the world's 1.2 billion Roman Catholics Thursday with prayers and a celebration of Mass with the cardinals who elected him.
He has set the tone for his papacy by wearing simple garments and avoiding the more luxurious trappings of the papacy. Earlier Thursday, he took a plain Vatican car to a basilica devoted to the Virgin Mary to pray. He later stopped by a Vatican hotel to pick up his belongings and paid the bill himself.
Pope Francis's formal inauguration Tuesday will be attended by foreign delegations, including a U.S. delegation led by Vice President Joe Biden, who is a Catholic.
Pope Francis succeeds Benedict, who is now known as pope emeritus.
The new pope, formerly Cardinal Jorge Bergoglio of Argentina, is the first Jesuit - a priest of the Society of Jesus - to be elected to lead the global church and the first of 266 popes throughout the past 2,000 years to take the name Francis.
Argentines are ecstatic about the selection of the first pope from their country, as were Hispanics in the rest of Latin America and elsewhere.
About 40 percent of the world's Catholics live in Latin America, with Brazil and Mexico having the largest Catholic populations.
Pope Francis, like the 13th century saint whose name he has chosen - St. Francis of Assisi - is noted for his humility and commitment to social issues.
The new pope has been criticized in Argentina for his firm opposition to same-sex marriage and abortion. In addition, a complaint was once filed there claiming he failed to denounce atrocities committed by Argentina's military government between 1976 and 1983.