The Expression Doctrine is dead. It is already useless, in the sense that it produces no answers to modern questions. One way or another, it is going to replaced with something. The question is whether it will be something ad-hoc, or well-principled.
We see that there is a well-principled alternative to the Expression Doctrine, based on a more reasonable understanding of the way communication works. By separating the concrete parts of the message from the dynamic parts of the message, and handling them separately, we can create principles that are much more useful. Laying down the exact principles is a matter of law, but I show how they can be constructed by showing some examples of how these principles make it possible to make rational laws, such as in the field of compulsory music licensing.