THIS BOOK, written fifty years ago, was among the first calls for a new system of values to govern the relationship between humanity and our planet. It has at least two claims on our attention. First, it contains a passionate and reasoned plea for the rights of non-human life. Second, Patrick Duncan proposes a new ethic which might enable fractious humanity to come together and help save the world from disaster. Patrick Duncan was exceptional in being an innovative thinker with a breadth of understanding which spanned philosophy, ethics, law and science; and a political activist who dedicated...