There is no direct link or relation between Ba Gua (as a martial art) to I Jing (the book of Change).
However, the principle and concept of I Jing has strong influence to Ba Gua practice.
For those who want to take Ba Gua as a practice for health purpose, I Jing will be a very important document to guide the internal practice. Or we can say that most of the internal practice for health purpose of Ba Gua comes from I Jing study.
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