An idea you generate, including the words through which it is expressed, is protected from others by virtue of your self-ownership. If the expression is private, then there is no way other people can use your idea without violating your autonomy. To use a B-movie scenario, they would have to torture you to obtain the rocket fuel formula…or, at least, rifle through your desk drawers. Just as you have a natural right to speak so, too, do you have a right to be silent and to preserve the idea for your own use.
When you publicly express an idea, you lose the shield of protection offered by your autonomy. Public expression is the equivalent of throwing the idea onto the wind in much the same manner as you might toss dollars out of a window. Strangers who gather up the discarded bills are no more thieves than those who use the distributed idea.
The only valid way to protect a distributed idea is through contractual rights such as those embodied in non-disclosure agreements. If you distribute the idea to people who have agreed to confidentiality in advance, then you have a limited but enforceable claim against them if they breach the agreement. You retain control of the idea. Without such an agreement, you have thrown the idea onto the wind.
Thus, I advocate a free market copyright that is enforceable by virtue of an explicit contract. I attempt to be meticulously clear because my position is often portrayed as “anti-copyright.” This is inaccurate. I am anti-state; I am anti-intellectual property as a natural right. But I want every single protection for my ideas that can be achieved through the consent of others. Why do I want protection? For the same reason George Bernard Shaw rejected it. Shaw said he did not want to be paid 30 or 300 times for the same piece of work. For myself, I like the idea of repeated payments but I do not like it enough to use the state as an enforcement arm or to claim natural rights where I know none exist.