John Winfield Stephenson (b. August 9, 1923 - May 15, 2015) was an American actor and voice actor. He worked in the animation business (particularly Hanna Barbara) beginning in the early 1950's, with some of his most recognizable characters being Mr. Slate from The Flintstones, Doggie Daddy from Augie Doggy, Captain Murphy from Sealab 2020, General Flagg and Col. Sharp from G.I. Joe: A Real American Hero and Professor X from Pryde of the X-Men.
Due to declining health and the onset of Alzheimer's, Stephenson retired from voice acting in 2010. He passed away in 2015 at the age of 91.
FLINTSTOOOOONE!!