Final answer:
People who attended Plato's lectures on goodness and morality were surprised by his use of rational philosophy rather than mythological accounts to establish a moral order, leading to the development of ethics based on the Forms of ideals like goodness, justice, and beauty.
Step-by-step explanation:
When people came to hear Plato lecture on goodness and morality, they were often astonished to hear discussions that strayed from traditional mythological explanations of moral order. Instead, Plato, influenced by Socrates, pursued the concept of goodness through the use of reasoning rather than through the inconsistent stories of the Greek gods, challenging the traditional basis for morality and social order. Plato's philosophy elevated the idea of abstract forms, like that of the good, the just, or the beautiful, as real and eternal, existing in a realm of perfect, unchanging ideas. Plato argued for an absolute and objective standard of goodness, which existed beyond the capricious actions and decisions of the gods, and could serve as the foundation of ethics and morals.
Relevant discussions in Plato's work occur in The Republic, where he explores the concept of the Form of Good. Like the sun that enables our sight, the Form of Good illuminates the intellect and allows the philosopher to perceive and understand the truly real and valuable aspects of existence, leading them towards the ultimate truths of the world. Socrates also contributed significantly to ethical philosophy with his questioning of whether the gods' actions were good in themselves or because they corresponded to a higher, independent standard of the good—a revolutionary step towards a secularized basis for morality.