For the leaf lives its appointed time and does not struggle against the wind that carries it away. The leaf does no harm, and finally falls to nourish new leaves.
In The Wheel of Time, the Way of the Leaf is completely pacifistic philosophy that forbids violence, or even touching a weapon. This is because they believe that violence will always in the end harm the one doing it more than one getting killed. It is followed by people called Tuatha'an, and it is essentially modern form of the Covenant.
See also Da'shain Aiel, Aiel, the Way of the Coconut.