Muhammad Ali fought bloody wars against a slew of boxing greats. But his toughest fight took place outside the ring against an opponent that couldn’t be knocked out. For three decades, Ali waged a public battle against Parkinson’s disease — making brave appearances long after the degenerative disorder withered his body and stole his speech. “Selflessness and bravery — those are the two things he epitomized,” said Leslie Chambers, president and CEO of the American Parkinson Disease Association. “He brought the average American’s attention to this disease,” Chambers said. “We’re so grateful for him. In the long run, he’s helped our community in a tremendous way.” Ali was just 42 years old when he was diagnosed with Parkinson’s in 1984, three years after the last fight of his legendary career. The disease ravages the body over time in a slow, savage march. People close to Ali noticed that his speech was already starting to slur and his body already starting to slow before his last bout in 1981.

Stephen William Hawking CH CBE FRS FRSA (8 January 1942 – 14 March 2018) was an English theoretical physicist, cosmologist, author, and Director of Research at the Centre for Theoretical Cosmology within the University of Cambridge. His scientific works included a collaboration with Roger Penrose on gravitational singularity theorems in the framework of general relativity and the theoretical prediction that black holes emit radiation, often called Hawking radiation. Hawking was the first to set out a theory of cosmology explained by a union of the general theory of relativity and quantum mechanics. He was a vigorous supporter of the many-worlds interpretation of quantum mechanics. Hawking was a Fellow of the Royal Society (FRS), a lifetime member of the Pontifical Academy of Sciences, and a recipient of the Presidential Medal of Freedom, the highest civilian award in the United States. In 2002, Hawking was ranked number 25 in the BBC's poll of the 100 Greatest Britons. He was the Lucasian Professor of Mathematics at the University of Cambridge between 1979 and 2009 and achieved commercial success with works of popular science in which he discusses his own theories and cosmology in general. His book A Brief History of Time appeared on the British Sunday Times best-seller list for a record-breaking 237 weeks. Hawking had a rare early-onset slow-progressing form of motor neurone disease (also known as amyotrophic lateral sclerosis "ALS" or Lou Gehrig's disease) that gradually paralysed him over the decades. Even after the loss of his speech, he was still able to communicate through a speech-generating device, initially through use of a hand-held switch, and eventually by using a single cheek muscle. He died on 14 March 2018 at the age of 76.

John Charles Hockenberry (born June 4, 1956) is an American journalist and author. Hockenberry has reported from all over the world, reporting on a wide variety of stories in virtually every medium for more than three decades. He has written dozens of magazine and newspaper articles, a play, and two books, including the bestselling memoir Moving Violations: War Zones, Wheelchairs, and Declarations of Independence, which was a finalist for the National Book Critics Circle Award, and the novel A River Out Of Eden. He has written for The New York Times, The New Yorker, Wired, The Columbia Journalism Review, Metropolis, and The Washington Post. Hockenberry has appeared as a presenter or moderator at many design and idea conferences around the world including the TED conference, the World Science Festival in New York and in Brisbane, the Mayo Clinic’s Transform Symposium and the Aspen Comedy Festival. He has been a Distinguished Fellow at the MIT Media Lab and serves on the White House Fellows Committee. He is a prominent figure in the disability rights movement; Hockenberry sustained a spinal cord injury in a car crash at the age of 19, which left him with paraplegia from the chest down.

Nancy Pedrick Mairs was an author who wrote about diverse topics, including spirituality, women's issues and her experiences living with multiple sclerosis. She was born on July 23, 1943 in Long Beach, California. She grew up in Boston, Massachusetts, however. She received an AB from Wheaton College, and an MFA in writing and a Ph.D. from the University of Arizona. She was diagnosed with MS when she was 28, and wrote several essays on her experiences as a self-described "cripple", including "On Being a Cripple," "Sex and the Gimpy Girl," and the memoir Waist High in the World. Mairs died in Tucson, Arizona on December 3, 2016.

Kyle Maynard (March 24, 1986) is a speaker, author, and mixed martial arts athlete, known for becoming the first quadruple amputee to ascend Mount Kilimanjaro without the aid of prosthetics. Although he was born with a rare condition known as congenital amputation, where fibrous bands prevent the development of fetal limbs, Maynard decided to pursue involvement in sports, first in youth league football, where he played nose tackle for the Collins Hill National Eagles at age 11. He wrestled in high school, ultimately winning 36 matches in his senior year of high school. He went on to place 12th in the 103-pound weight class. Maynard also began weight training, and was awarded the title of GNC’s World’s Strongest Teen by bench pressing 23 repetitions of 240 lbs. The same year, he received the ESPN Espy Award for Best Athlete With A Disability in 2004. Maynard appeared in both Vanity Fair and the Abercrombie & Fitch Stars on the Rise catalog. He was also the recipient of the 2004 President's Award for the Sports Humanitarian Hall of Fame. He went on to attend the University of Georgia and was a part of their wrestling team, but left shortly after starting his education to promote his book and pursue a speaking career. While attending the University of Georgia, he began work as a speaker for the Washington Speaker's Bureau, specializing in motivational speeches. He was also featured on talk shows including The Oprah Winfrey Show and Larry King Live.