System taekwondo GUB to DAN

System taekwondo GUB to DAN
The system start ti Taekwondo is the GUB and arrives at DAN.
Nine are the sum of the components of heaven, earth, Yin and Yang, The GUB system is decreasing, 9-1 and Dan system is increasing, 1-9.
This system in oriental symbolizes all forms of life come down from heaven, live on land and return from whence they came.
In the decimal system unit 9 is also the highest number.


Source: Taekwondo