The ancient world may have been a bad and backward place in some ways, but it is the Greeks and Romans who gave us the tools and values we needed to move forward. The following points are all direct quotes. Science, research, and the acquisition of knowledge itself are to remain apart from both religious and political authority. Military power operates under and is checked by civilian control. The notion of dissent and open criticism of government, religion, and the military.
Human nature is constant over time and space.
Word must match deed. The Supremacy of Culture. That is a different reality and can be evaluated on absolute criteria. There was no Pyramid of Pericles, no Great Palace of Epaminondas, no mummified Aristides. Hanson and Heath discuss in great detail the things which make Western culture unique and which endow it with both value and peril.