Private property ordinarily triggers notions of individual rights, not social obligations. The core image of property rights, in the minds of most people, is that the owner has a right to exclude others and owes no further obligation to them. That image is highly misleading. Property owners owe far more responsibilities to others, both owners and non-owners, than the conventional imagery of property rights suggests. Property rights are inherently relational, and because of this characteristic, owners necessarily owe obligations to others. But the responsibility, or obligation, dimension of private ownership has been sorely under-theorised. Inherent in the concept of ownership is an implicit norm that might be called the social-obligation no...