Jeet Kune Do Training
JKD as it survives today - if one wants to view it "refined" as a product, not a process - is what was left at the time of Bruce Lee's death. It is the result of the life-long martial arts development process Lee went through. Bruce Lee stated that his concept is not an "adding to" of more and more things on top of each other to form a system, but rather, a winnowing out. The metaphor Lee borrowed from Chan Buddhism was of constantly filling a cup with water, and then emptying it, used for describing Lee's philosophy of "casting off what is useless". He also used the sculptor's mentality of beginning with a lump of clay and hacking away at the "unessentials"; the end result was what he considered to be the bare combat essentials, or JKD.

The core concepts of JKD are derived from Wing Chun. This includes such ideas as centerline control, vertical punching, trapping, and forward pressure. Through his personal research and readings, Lee also incorporated ideas from boxing and fencing. Later during the development of Jeet Kune Do, he would expand to include the art for personal development, not just to become a better fighter. To illustrate Lee's views, in a 1971 Black Belt Magazine article, Lee said "Let it be understood once and for all that I have NOT invented a new style, composite or modification. I have in no way set Jeet Kune Do within a distinct form governed by laws that distinguish it from 'this' style or 'that' method. On the contrary, I hope to free my comrades from bondage to styles, patterns and doctrines."

Said another way, Lee believed that only what worked should be used in martial arts and the rest discarded. And that's what makes Jeet Kune Do special. By the way, it's also what makes his ideology the precursor to modern day mixed martial arts.

Bruce Lee studied Wing Chun, an empty hand form of kung fu under Sifu Yip Man and one of his top students, Wong Shun-Leung, in China before leaving for the United States in 1959. With this training, he developed an understanding of striking through centerline control (protecting the middle so opponents had to attack from the outside). What's more, he gained a dislike for flashy movements and an understanding of how to intercept an attack before it had even started (an unorthodox method of countering). Beyond Wing Chun, Lee also studied both western boxing and fencing.

Lee felt the dynamic property of JKD was what enabled its practitioners to adapt to the constant changes and fluctuations of live combat. He believed that these decisions should be done within the context of "real combat" and/or "all out sparring" and that it was only in this environment that a person could actually deem a technique worthy of adoption.

The overriding principle of Jeet Kune Do is to eliminate what doesn't work and use what does. This isn't just a global ideology, either. There is also an individual component to the Jeet Kune Do philosophy, where the strengths and weaknesses of practitioners are taken into account when practicing and formulating their martial arts plan. With all of that said, there is a framework that is utilized to allow for this, which sometimes varies depending on the branch or substyle being of JKD being offered. Regardless, here are some of the important and rather universal points.

Centerline Control: Lee's Wing Chun training taught him to protect his centerline so attackers were forced to try and strike from the outside in. This is a staple of JKD.

Combat Realism: AKA- forget kata. Some martial arts styles swear by kata, or pre-arranged fighting movements conducted in isolation where practitioners are asked to pretend that they are taking on attackers while delivering punches or kicks. JKD and Lee did not subscribe to the kata philosophy, nor any flashy movements or point sparring measures. Rather, they believed that learning in such a manner sometimes fooled martial artists into a false sense of combat security, as many of the moves being practiced did not work in real life.

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Jeet Kune Do Training