The mayor recalled how in 1971 he listened on the radio to the first heavyweight championship fight between Ali and Joe Frazier, the Philadelphia boxing legend who died last year. He paused to explain to the younger members of the Constitution Center audience how people his age once gathered around strange, boxlike devices to hear broadcasts of sports events.
By then, Ali, though unbeaten in the ring as a professional, had been stripped of his title, faced prison, and become a polarizing figure - all over his refusal to be drafted to fight in the Vietnam War. His boxing license was restored only after the U.S. Supreme Court voided his five-year sentence.
Frazier, also unbeaten, won the 15-round "fight of the century" in Madison Square Garden in New York City, but Ali captured the final two dramatic bouts between them - the last one the celebrated "Thrilla in Manila" in 1975.
Center president David Eisner noted Thursday that the nation's founding document is at an important juncture, and that Ali "will be the face of the Constitution's 225th anniversary."
"Muhammad Ali symbolizes all that makes America great, while pushing us as a people and as a nation to be better," he said.
Efforts to reach an Ali representative were unsuccessful. The award carries a $100,000 prize.
Eisner acknowledged that even in his infirmity, Ali remains controversial.
"Not everyone is a great fan of Muhammad Ali, or that he was a conscientious objector," Eisner said. But all should respect the principles that led Ali to take his battle over military induction to the Supreme Court, he said.
That battle began, in a way, in 1964, when the man born as Cassius M. Clay Jr. announced that he had joined the Nation of Islam - and soon changed his name.
In 1967, Ali cited his religious beliefs and his opposition to the Vietnam War in resisting the draft, leading to his prosecution.
"How can I shoot them poor people?" Ali asked. "Just take me to jail."
While living in a Spanish-style mansion in Cherry Hill, Ali was regularly seen with his friend and neighbor Major Coxson, who unsuccessfully ran for mayor of Camden despite a lengthy criminal record.
Ali would jokingly call Coxson "the gangster" - no longer funny after Coxson was executed gangland-style by Black Mafia gunmen inside his Cherry Hill home in 1973.
Ali told Maury Z. Levy, then editorial director of Philadelphia magazine, that he had been living in Philadelphia, but his house felt small.
"So then the Major showed me another house in Cherry Hill, this big, beautiful Spanish hacienda. I went and looked at it and didn't like it because I figured it was too far from Philly. I like to live around people and everything.
"But I got to start hanging around with the Major a lot over there, he lives down the block, and I got to like the peace and serenity of it, being away from the people."
For older generations, Ali is seen as possibly the greatest boxer of all time. He reclaimed his title in 1974 in another famous fight, the "Rumble in the Jungle" in D.R. Congo (then Zaire), knocking out George Foreman, who had gained the title by knocking out Frazier. Ali then lost and regained the crown a third time.
Younger generations know him for his battle with Parkinson's and his role in promoting peace around the world. Among other efforts, he has completed goodwill missions to Afghanistan and North Korea, has delivered $1 million in medical aid to Cuba, and secured the release of 15 hostages from Iraq during the first Gulf War.
Last year's medal went to former U.S. Secretary of Defense Robert Gates. The award, first presented in 1989, has also gone to Nelson Mandela, Shimon Peres, Kofi Annan, Sandra Day O'Connor, and Bono.
The 2012 medal will be presented on the evening of Sept. 13 as part of the celebration of the Constitution's anniversary. The night will mark Ali's return to the Constitution Center, where he was first to raise the flag in the Grand Hall Overlook during a special Flag Day ceremony in 2003.
"Muhammad Ali represents how far we have come as a nation," said Doug DeVos, chairman of the center executive committee, "and the spirit of determination, ambition, and civic service that will propel America forward for 225 more years and beyond."
Contact Jeff Gammage at 215-854-2415, firstname.lastname@example.org, or on Twitter @JeffGammage.