Kyokushin kaikan (極真会館, Kyokushin kaikan) is a style of stand-up, full contact karate, founded in 1964 by Masutatsu Oyama (大山倍達, Ōyama Masutatsu?) who was born under the name Choi Yong-I (최영의). Kyokushinkai is Japanese for "the society of the ultimate truth." Kyokushin is rooted in a philosophy of self-improvement, discipline and hard training. Its full contact style has had international appeal (practitioners have over the last 40+ years numbered more than 12 million).