Taegeuk Sa Jang (also spelled Taegeuk Sah Jang) is the fourth of eight "taegeuk" forms (i.e., poomsae) used by Kukkiwon and World Taekwondo (WT). The word "Sa" is the number 4 in the sino-Korean numbering system. Each taegeuk form is represented by a trigram (such as ☳); trigrams are divination symbols derived from the I Ching. The trigram for Taegeuk Sa Jang represents the concept of "Jin." Jin represents thunder, symbolizing great power and dignity. The power can be seen, for example...