Perhaps the most approachable book for the lay reader — lucid and personable — by science writer Matt Ridley. He explains: "Our minds have been built by selfish genes, but they have been built to be social, trustworthy and cooperative. This is the paradox this book has tried to explain." It is an excellent guide to how scientists solve the central puzzle (setting aside the author's brief anti-government tirade in the final chapter). Comments about the scientists and their research further enrich understanding of the nature of science.