A friend of mine who teaches Yang style T'ai Chi once asked me if I knew about the 3 Inners and Outers.
What he meant are the six harmonies, typically divided into the the 3 internal and 3 external co-ordinations. These are:
- The hands co-ordinate with the feet
- The shoulders co-ordinate with the hips
- The elbows co-ordinate with the knees
- The heart co-ordinates with the intent
- The intent co-ordinates with the Chi
- The Chi co-ordinates with the power
I knew these as part of the 10 co-ordinations, which are:
- The head must co-ordinate with the coccyx
- The neck must co-ordinate with the waist
- The shoulders must co-ordinate with the inside of the thigh, where it joins the body
- The elbows must co-ordinate with the knees
- The shin of one leg must co-ordinate with the shin of the other leg
- The toes of one foot must co-ordinate with the toes of the other foot
- The spirit must co-ordinate with the mind
- The mind must co-ordinate with the Chi
- The Chi must co-ordinate with the strength
- The inner aspects (spirit, Chi) must co-ordinate with the outer aspect ( the external form )