The Ryōi Shintō-ryū Jūjutsu transmission document - 'Shinto Yawara Hisho' (心當和秘書) states that:

"At the moment you face the enemy, our intention’s movement come naturally. Earth (Chi) calm Yin and heaven movement Yang. The movement is the Yang’s principle manifestation and represents the heaven (Ten). The technique’s form creation follows the same logical principle as the manifestation of the forms of one thousand living thing’s. However, all of those forms and a hundred thousand techniques created, cannot be grasp if you loose your Tanden’s Ki."