premise: Floyd Mayweather Jr. is incapable of boxing.
hypothesis: Floyd Joy Mayweather Jr. ( born Floyd Joy Sinclair ; February 24 , 1977 ) is an American former professional boxer who competed from 1996 to 2015 , and currently works as a boxing promoter . Widely considered to be one of the greatest boxers of all time , undefeated as a professional , and a five-division world champion , Mayweather won fifteen world titles and the lineal championship in four different weight classes ( twice at welterweight ) . Mayweather is a two-time winner of The Ring magazine 's Fighter of the Year award ( 1998 and 2007 ) , a three-time winner of the Boxing Writers Association of America ( BWAA ) Fighter of the Year award ( 2007 , 2013 , and 2015 ) , and a six-time winner of the Best Fighter ESPY Award ( 2007 -- 2010 , 2012 -- 2014 ) . In 2016 , Mayweather was ranked by ESPN as the greatest boxer , pound for pound , of the last 25 years . He is also regarded as the best defensive boxer in the sport , as well as being the most accurate puncher since the existence of CompuBox , having the highest plus -- minus ratio in recorded boxing history .