Context: On the assumption that intellectual property rights are actual rights Stallman argues that this claim does not live to the historical intentions behind these laws, which in the case of copyright served as a censorship system, and later on, a regulatory model for the printing press that may have benefited authors incidentally, but never interfered with the freedom of average readers. Still referring to copyright, he cites legal literature such as the United States Constitution and case law to demonstrate that it is meant to be an optional and experimental bargain that temporarily trades property rights and free speech for public, not private, benefit in the form of increased artistic production and knowledge. He mentions that "if copyright were a natural right nothing could justify terminating this right after a certain period of time".

Question: Stallman thinks what type of IP historically served as a censorship system?
Answer: copyright

Question: What does Stallman think copyright served as a regulatory model for?
Answer: the printing press

Question: What does Stallman think was meant to be optional and experimental?
Answer: copyright

Question: What does Stallman think copyright was supposed to trade temporarily for public benefit?
Answer: property rights and free speech

Question: Who pointed out that "if copyright were a natural right nothing could justify terminating this right after a certain period of time"?
Answer: Stallman

Question: What does Stallman say that censorship is a form of?
Answer: Unanswerable

Question: What was censorship a regulatory model for?
Answer: Unanswerable

Question: What does Stallman say is meant to be mandatory?
Answer: Unanswerable

Question: What restricts free Speech?
Answer: Unanswerable

Question: What does Stallman say is a natural right?
Answer: Unanswerable