Quote Originally Posted by yogi_berra View Post
Authoritarian, not authoritative. One license offers the freedom of the former Soviet Union, you are free to do whatever you want as long you give up your own rights.
The GPL is a conditional offer of a privilege, subject to the property right of the copyright holder in their copyright. Is that not precisely the same right that must be used to add GPL-incompatible conditions (software patents notwithstanding)?