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Former Secretary of State Hillary Clinton today called Nelson Mandela "a giant among us," whose "unconquerable" soul "demonstrated unequivocally how each of us can choose how we will respond to those injustices and grievances, those sorrows and tragedies that afflict all of humankind."

"Nelson Mandela will be remembered for many things," Clinton began. "He will be certainly remembered for the way he led, his dignity, his extraordinary understanding not just of how to bring democracy and freedom to his beloved South Africa, but how important it was that he first brought freedom to himself."

Clinton, who as first lady was in attendance at Mandela's inauguration in 1994, recalled that during her encounters with Mandela, "I was always struck by the extraordinary depth of his self-knowledge, of his awareness about how hard it is to live a life of integrity, of service."

"I only hope that as we both mourn and celebrate the passing of this universally recognized and beloved figure, that we remember he became that through an enormous amount of hard work on himself," she said.

Clinton was speaking at the U.S. Capitol where she was honored with the Tom Lantos Prize for Human Rights. After she accepted the honor, she remarked how much Mandela was like Lantos, a Holocaust survivor who later served in Congress.

"Here were two men who had seen the worst that humanity can offer; who had been objectified, denied their right to be a Jew in Hungary during the Holocaust or a black man in South Africa during apartheid. They had every reason to come out, if not embittered, cynical; believing that for the rest of their lives, the only thing that would matter was acquiring power, being able to demonstrate their influence, especially as against those who had denied them the right to be who they were," she said. "What always struck me about Nelson Mandela and Tom Lantos was the joy, the curiosity, the enthusiasm for life that they brought with them out of the depths of such suffering."

The Tom Lantos Human Rights Prize is awarded annually to raise awareness about human rights "to bring to the attention of the world the brave individuals who are committed to fighting for justice across the globe," according to the Lantos Foundation.

As she left the building, Clinton, the presumptive frontrunner for the Democratic nomination for president in 2016, paid no attention to a question asking whether she is gearing up for another presidential campaign.

The former secretary of state also ignored a man who confronted her as she boarded an elevator who asked whether her response to the Benghazi terrorist attacks on Sept. 11, 2012, would have been different had her daughter Chelsea been the ambassador to Libya. An agent on Clinton's security detail put her hand in front of the man's cellphone camera until the elevator doors closed.