"Dan" means "single". [1]
The concept of "one" was very important in the Taoism. One meant "single", which was in turn equivalent to Dan. This connection demonstrated the process of evolution and branding throughout the Taoist history.
Therefore, the so-called "Dan-bearing" in Taoist jargon was referring to a state when the Qi inside one’s body was mellow and plenty enough to dispel the pathogenic energy, prolonging one’s life.
Another example would be the term "Yuan Ying"[2], which was referring to the recovery of one’s original simplicity; by condensing one’s vital essence inside one’s body, one could create another self in pure-energy form, as primordial as a baby.
However, as time passed, these concepts were misinterpreted by later generations. Dan-bearing was translated into the production of a tangible ball resembling a glass marble, while Yuan Ying became a bouncing and vivacious little man.
Bullshit.
