Greek ways of thinking -- Matter and form : (ionians and pythagoreans) -- The problem of motion : (Heraclitus, Parmenides and the pluralists) -- The reaction towards humanism : (the Sophists and Socrates) -- Plato (I) : the doctrine of ideas -- Plato (II) : ethical and theological answers to the sophists -- Aristotle (I) : the aristotelian universe -- Aristotle (II) : human beings