Timeline of Major Ethical Philosophies

  • 624 BCE

    Thales of Miletus

    Thales founded the Milesian School of natural philosophy and Anaximander was his student. They sought naturalistic explanations for the world through observation and rational thinking, rather than relying on mythology or supernatural beliefs. Anaximander's ideas were influential in the development of Western philosophy, astronomy, biology, and geography, and laid the foundation for the scientific method.
  • 585 BCE


    Anaximenes, a Greek philosopher, made significant contributions to physical sciences. He was the first to distinguish between planets and stars and used his principles to explain natural phenomena, including thunder, lightning, rainbows, and earthquakes. Although his book on philosophical views survived into the Hellenistic period, there are no remains of it today. Anaximenes' primary interest was in identifying the single source of all things in the universe, which he called Monism.
  • 579 BCE

    Pythagoras of Samos

    Pythagoras was a Greek philosopher and mathematician who is best known for the Pythagorean theorem. Pythagoras was also the founder of the Pythagorean school of philosophy, which emphasized the importance of mathematics, music, and astronomy in understanding the world. Pythagoras believed that everything in the universe was related to numbers and that the study of mathematics could reveal the underlying order of the cosmos.
  • 427 BCE


    Plato was a Greek philosopher and student of Socrates, known for his contributions to metaphysics, epistemology, ethics, and political theory. He founded the Academy in Athens, wrote numerous philosophical dialogues, and believed in the existence of an objective reality and the importance of knowledge of the Forms for understanding reality and achieving a just society. His ideas have had a profound influence on Western thought.
  • 384 BCE


  • 384 BCE

    Virtue Theory

  • 341 BCE


  • 334 BCE

    Zeno of Citium

  • 354

    St. Augustine of Hippo

  • 1225

    St. Thomas Aquinas

  • Immanuel Kant

  • Deontology

  • Utiliatarianism

  • Justice Theory

  • John Rawls

  • Jürgen Habermas