A contradiction lies at the core of the modern law of speech and property. The contradiction is captured by four propositions, all of which are widely accepted, but all of which cannot be true. Proposition 1: freedom of speech is not subject to political revision. Of course, beneath this seemingly simple statement lies a body of immensely complex doctrine. The proposition says nothing about what freedom of speech consists of or what levels of review should apply to political decisions regulating or channeling speech. Still, few would quarrel with the notion that there is some core content to the freedom of speech and that this core content is constitutionally protected. Proposition 2: within broad limits, economic entitlements are subject to political revision. As we shall see, this proposition has not always been true, and it is not completely true now. As a generalization, though, it is not only true but also a central tenet of the modern regulatory state. Of course, the Constitution prevents the taking of property unless the taking is for a public use, and just compensation must be paid for certain kinds of interferences with property rights. But courts have read the public use requirement very broadly. As a consequence, if the government is willing to pay for property, it can usually seize it. Moreover, even if the government is unwilling to pay, it can usually regulate and restrict property rights very extensively. If the economic entitlement does not count as property, then the scope of permissible political revision is even broader.

Proposition 3: the freedom of speech does not include the right to use another person’s property in order to convey one’s message. This proposition is also less true than one might think, but it is nonetheless often true, and it captures an intuition that most people unreflectively hold. For example, when the Supreme Court upheld the free speech right of a protestor to burn an American flag, it took pains to point out that “nothing in our opinion should be taken to suggest that one is free to steal a flag so long as one later uses it to communicate an idea.” Similarly, the Court has made clear that no one has the constitutional right to commandeer someone else’s printing press, or automobile, or shopping center to engage in communication.

Proposition 4: all speech requires the use of some property. For the most part, speech requires the use of a physical object, whether it is a megaphone, paper and pen, a printing press, a television camera, or a computer terminal. Even speech that depends on nothing more than the human vocal cords must occur somewhere. The physical things that speakers use and the physical places where they use them are owned by someone. Without access to these things and places, no speech is possible.

These four propositions cannot be reconciled. If it is true that economic entitlements, including most property rights, are subject to political revision, and if it is true that there is no right to use another’s property for speech, and if it is true that speech requires property, then it cannot also be true that speech rights are immune from political revision.