A BSD license gives the user near absolute freedom to do what one wishes with a piece of source code -- they can sell it, modify and make proprietary, integrate

A BSD license gives the user near absolute freedom to do what one wishes with a piece of source code -- they can sell it, modify and make proprietary, integrate with existing proprietary licensed projects, etc. On the other hand, the GPL imposes heavy restrictions on what a user can do with a software's source code in order to preserve other users' freedoms. That's the fundamental split in permissive licenses vs copyleft licenses. It has been argued to death and the author probably (correctly) assumed that most readers are already familiar with it.