Here’s an unexpected reversal: It’s not so much that civilization developed water-borne sewerage systems as much as it’s that the cultural values of cleanliness that made it imperative for certain cultures to distance themselves  from their body waste that made civilization possible. Toilets and sewage systems are more important than banks and art galleries and have to come first. Cultures that sexualize the public area lose economic vitality. Why premature sexualization of youngsters dooms them to poverty. How a certain ‘redhead’ contributed to economic and military decline. How they got enough water into New York in the 1840s. Why it takes 3 or more people to sustain 2 elderly people even if the old-timers have retirement plans and pensions. What distinguishes humans who are creators from humans who are consumers. Why a prominent Stanford professor who got it all stupendously wrong fifty years ago is still teaching. At the angel end, people aspire to greatness, creativity, achievement and accomplishment. At the other end of the spectrum, people aspire to eat, have sex, indulge drugs and alcohol, and seek entertainment and luxury. To flourish, a society can't have too many of the angel-type people. To survive, a society can't have too few of the other end people.