premise: Parkinson's disease has afflicted professional boxer Muhammad Ali.
hypothesis: Muhammad Ali ( [ ɑːˈliː ] born Cassius Marcellus Clay Jr. ; January 17 , 1942 -- June 3 , 2016 ) was an American professional boxer and activist . Parkinson's disease . People with parkinsonism who have increased the public 's awareness of the condition include actor Michael J. Fox , Olympic cyclist Davis Phinney , and late professional boxer Muhammad Ali .