"Any mankind person worth his salt can simultaneously incubate whole clutches of ideas that are either contradictory or mutually exclusive. For instance, mankind has persuaded itself that its race is perfectible, though it hasn’t changed physically, mentally, or psychologically since the Cro-Magnon. Mankind has also persuaded itself that each individual is unique, though each person shares ninety-nine and ninety-nine one hundredths of his DNA and roughly the same percentage of his ideas with thousands or even millions of other persons."