The Earth Element's organs are Spleen and Stomach. It is the digestive system and it control the muscle.
Yin and Yang relationship deals with how fast the person move, or which muscle group the person tend to use - Long muscle, suited for marathon, or Short muscle, suited for short distance.
"Promise" is the most Yin. It consist of mostly seed oil, which is the stored energy of winter. The person who choose this tends to be slower but more consistent.
"Symbiosis" is the Yin. The person who choose this is a people people. He would make an offering of sweetness in order to place himself in advantageous position among a group.
"Tranquility" is the neutral. The person who choose approach the task with ease, or needs the easy going temperament.
"Delight" is the Yang. The person who choose this focus on light.
"Agility" is the most Yang. The person who choose this uses the fast muscle. He may move fast and tries to get things done, or would like to gain the speed.