The classic sayings about kindness include:

1. Those who are kind will be kind to others.

2. The most beautiful music of the soul is kindness.

3. Sincerity is the highest virtue in life.

4. Sincerity is an openness of the soul.

5. Be a kind person and seek happiness for the masses.

6. Good and evil are two sides of the same coin.

7. All evil comes from selfishness, and the good thing that leads to all lies in not being selfish, and even sacrificing oneself for the common good.