Six Levels of Internal Martial Arts
Level One: Li (力) - Muscular Contraction. Typically referred to as 'using muscle' or 'muscular force'
Level Two: Jing (勁) - While this is typcially referred to energetically, it can also be defined in contrast with the above. That 'energy' must flow through releaseed muscles so: Muscular Release.
Level Three: Yí (意) - Intention (not 'mind' or thought - the characters show an open mouth over the Heart - voice of the heart)
Level Four: Qi (氣) - Energy (Difficult to talk about, but can be thought of as body activation that does not solidify into a shape)
Level Five: Shén (神) - Typically a kind of 'spirit' or 'energy' manifested. In this context a kind of 'personal essence' or 'consciousness' (the cauldron/container that the above four play in)
Level Six: Kong (空 虛) - Emptiness (full release)