Ginsberg manifested an 'objectivist' theory of ethics in the tradition of Plato, Aristotle, Mill, Sidgwick and Hobhouse. This led him to maintain that 'value' and 'obligation', 'good' and 'bad' are terms not further reducible or analysable into each other or into terms not implying them. He also deals positively with the notion of levels of moral development, and suggests criteria for assessing these. Using these criteria it is possible to detect unmistakable differences of level between different societies in the modern world. He saw clearly that there is no finality in these matters, and that conditions, circumstances and societies change, involving advances and regressions.