Matt Ridley, Genome: The Autobiography Of A Species In 23 Chapters Quotes
Stress can alter the expression of genes, which can affect the response to stress and so on. Human behavior is therefore unpredictable in the short term, but broadly predictable in the long term.
TP53 seems to encode the greater good, like a suicide pill in the mouth of a soldier that dissolves only when it detects evidence that he is about to mutiny.