First, good for good is an inherent feature of kindness. Not only do you have to repay the kindness of others, but you also have to give to others yourself.

from: [Ancient Greece] Aristotle: The Ethics of Nico Kyle

Introduction: Aristotle (384-322 BC), an ancient philosopher and ancient Greek, was one of the great philosophers, scientists and educators in the ancient history of the world, and he was a master of Greek philosophy. He is Plato's student and Alexander's teacher.

second, the benefactor should be careful that the beneficiary is not a treacherous person and will not repay kindness with evil.

from: [Ancient Greece] democritus: The Pieces of Works

Introduction: democritus (Greek: Δ η μ? κριτο? , about 46 ~ 37 BC), was born in the commercial city of Abdallah on the coast of Thrace, a great materialist philosopher in ancient Greece, and one of the founders of the theory of atomic materialism (first put forward atomism (everything is made up of atoms)).

third, a small favor given in time is of great value to the beneficiaries.

from: [Ancient Greece] democritus:

Fourth, the heart of repaying kindness is nobler than anything else.

from [ancient Rome] Seneca: Collection of Letters to Luxiliu

Introduction: Seneca (about 4-65 BC), an ancient Roman politician, Stoic philosopher, tragic writer and orator.

5. Only those favors that are not bought by money are worthy of thanks.

from [ancient Rome] Ovid: Poems of Love

Introduction: Ovid, an ancient Roman poet.