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On October 14, 1972, Warner Brothers release the series "Kung Fu" featuring a Shaolin priest - Kwai Chang Caine (David Carradine) and his journey through the old West. What was new to the American public was not only the fighting but the philosophy that was presented with each show. In each episode, Kwai Chang Caine recalls a memorable moment when his wise teachers, Master Kan (Philip Ahn) or Master Po (Keye Luke), taught him a lesson which provides an insight to his current problem. For many, this was a new experience and sparked an interest in Chinese Martial Arts and Chinese culture. Unfortunately, the show was cancelled after 63 episodes,on March, 1975. The series was brought back as "Kung Fu - the Legend Continues" in 1993 and lasted for another 88 episodes (4 seasons) but the second series never approached the sentiments of the original series.
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"As quickly as you can...snatch the pebble from my hand." [Caine tries and fails]
"When you can take the pebble from my hand, it will be time for you to leave."
Kwai Chang Caine (David Carradine) played the young grasshopper asking Master Kan (played by Philip Ah)
So there you have it. It's from the old TV Show "Kung Fu"

Some trivia for ya... David Carradine, the Young Grasshopper, plays "Bill" in Kill Bill.