Free-as-in-freedom FSF style implies the natural follow on question to "am I allowed to change it" is "how easy will it be for me to change it"...
PS. I think you might also want to review the comment guidelines on this site... e.g. "Please don't post shallow dismissals, especially of other people's work. A good critical comment teaches us something. "
PS. I think you might also want to review the comment guidelines on this site... e.g. "Please don't post shallow dismissals, especially of other people's work. A good critical comment teaches us something. "