Zeno of Citium was a Greek philosopher who founded the Stoic school of philosophy in Athens in the early 3rd century BC. Some synonyms for his name include Zeno the Stoic, Zeno the Philosopher, and Zeno of Cyprus. He was known for his teachings on ethics and his belief in the existence of an objective moral order. Zeno's influence can still be seen in modern philosophy, particularly in the emphasis on personal responsibility and the importance of living an ethical life. Despite living over two millennia ago, Zeno's ideas continue to be studied and admired by scholars and students around the world.