KangYu Ch.7-8

Heo-Sil

Kang-gi and Yu-gi, dependently upon their existence and non-exisitence of hardness and softness, can be the change of <Heo-Sil>.

“What are <Heo> and <Sil>? What has its appearance that has nothing intended in real is called <Heo>, while, on the contrary, what is filled with intention to do something regardless its appearance is called <Sil>.” “As you know what your motion should be like and you know what points you should attack and what points you should not, then, riding the flow of <Heo> and <Sil>, you can succeed in your offense at the opponent.”(Ch. 29)

For an example, consider the case the opponent kicks you. Its defending technique is to concentrate your strength on the soft part behind his Kang-gi. On the other hand, if you avoid it stepping slightly aside, it is a Yu-gi as you follow his approaching toward you. This technique is to lead his offense to vainness with your <Heo> to his <Sil>. On the other, if your opponent respond to your <Sil> this way, you can also respond to his <Heo> with your <Heo>, making your kicking to light stepping, that is, to a faint kick, so that you can give him a strong attack with the next swift kick helped by the tide from your serial stepping. This is possible because “<Heo> contains <Sil> while <Sil> contains <Heo>.”(Ch.29)

On the other hand, the technique of counter-kick of Taekwondo is to respond to the opponent's kick with your <Heo> thrusting his <Heo> that supports its <Sil> with your <Sil>. How can you do this? “Seek some empty points in the opponent's motion. Then, go into it.”(Ch.38)

All of these say, “you can have <Heo> as <Sil> and <Sil> as <Heo>, and it is so changeful that each of both follows including the other, which makes the flow of <Heo-Sil>.”(Ch.29)