One who is good at preserving life
does not avoid tigers and rhinoceroses
when he walks in the hills;
nor does he put on armor and take up weapons
when he enters battle.
The rhinoceros has no place to jab its horn,
the tiger has no place to fasten its claws.
Weapons have no place to admit their blades.
What is the reason for this?
Because on him there are no mortal spots.
Tao Te Ching, quoted in the book Deep Survival by Laurence Gonzales