Zeno of Citium (334 BC – 262 BC) was a Greek philosopher from Cyprus, and was the founder of the Stoic school of philosophy which he taught in Athens, from about 300 BC.

 All things are parts of one single system, which is called Nature; the individual life is good when it is in harmony with Nature.

Seeing that the universe gives birth to beings that are animate and wise, should it not be considered animate and wise itself?

Happiness is a good flow of life.

The end may be defined as life in accordance with nature or, in other words, in accordance with our own human nature as well as that of the universe.  [The “end” here means “the goal of life.”]

Love is a God, who cooperates in securing the safety of the city.

All the good are friends of one another.

We have two ears and one mouth, so we should listen more than we say.

As quoted in Diogenes Laërtius Lives and Opinions of Eminent Philosophers, vii. 23.

Variant translation: The reason why we have two ears and only one mouth is that we may listen the more and talk the less.

No evil is honorable; but death is honorable; therefore death is not evil.

A bad feeling is a commotion of the mind repugnant to reason, and against nature.

does not exercise reason; there is nothing more excellent than the universe, therefore the universe exercises reason.

If melodiously piping flutes sprang from the olive, would you doubt that a knowledge of flute-playing resided in the olive? And what if plane trees bore harps which gave forth rhythmical sounds? Clearly you would think in the same way that the art of music was possessed by plane trees. Why, then, seeing that the universe gives birth to beings that are animate and wise, should it not be considered animate and wise itself?