When people are born they are supple
and when they die they are stiff.
When trees are born they are tender
and when they die they are brittle.
Stiffness is thus a companion of death,
flexibility a companion of life.
So when an army is strong
it does not prevail.
When a tree is strong,
it is cut for use.
So the stiff and strong are below,
the supple and yielding on top.
 
A rather blunt marketing tool for Qigong, written several thousand years ago!