The foundation of Kuk Sool Won™ training is based on the theory of YU-WON-HWA.
From the theory of YU (flowing, as in water), we learn to "go with the flow." When we are pushed, we pull; when we are pulled, we push. Also, water symbolizes many things, not the least of which are adaptability, softness and at the same time, great force.
The theory of WON (circle) acknowledges that every person has his or her own circle of "private space." Attacks which invade this space should be redirected with flowing and circular defensive motions. This circle should be thought of as least resistance; always rolling (active), and therefore, difficult to hold or grasp.
Finally, the theory of HWA (harmony) represents the unity of mind and body. In practice, this is accomplished through repetition. Harmony is achieved within oneself, through a state of "emptiness" that recognizes "+" (yang) and "-" (um) are part of one; each is there to allow the other to exist, and cannot exist if the other part is not there.
The ramification of the theory of YOU-WON-HWA is that as flowing water seeks a harmonious state with its environment, constantly adapting to external changes, we should also seek to maintain harmony within our inner circle so that all trespassers in this space are redirected in direct proportion to the force they introduce.