 Green’s political philosophy is expressed in his posthumously published Lectures on the Principles of Political Obligation and his 1881 essay “Liberal Legislation and Freedom of Contract”. His perfectionist ethics influence his politics. He provides the philosophical foundations for a new progressive form of liberalism that transcends the laissez-faire liberalism characteristic of some strands in nineteenth century British liberalism (Nicholson 1990). The state has a duty to promote the common good, and individual rights are constrained by the common good. This gives the state not just negative duties to refrain from interfering with the freedoms of its citizens but also positive duties to provide resources and opportunities for individual self-realization.