Private property is a rather elusive concept. Any kid knows what it means for something to be mine or yours, but grownup legal theorists get flustered when they try to pin down the term. Typically they, actually we, turn to a familiar analytic toolkit: including, for example, Blackstone\u27s image of private property as sole and despotic dominion ; Hardin\u27s metaphor of the tragedy of the commons ; and, more generally, the division of ownership into a trilogy of private, commons, and state forms. While each analytic tool has a distinguished pedigree and certain present usefulness, each also imposes a cost because it renders invisible many new forms of property. This essay suggests that legal scholarship, particularly its law and- econom...