So-called "intellectual property" violates real property rights, plain and simple.
Agreed for the most part. I know of someone who refuses to copyright his online material because he believes that you shouldn't have contracts and/or agreements with the government, which is what he claims a copyright is. However, he claims ownership of his material, and requests people not steal it by duplicating it.
Does your musician friend *strongly request* that people don't copy the music he creates, or does he *threaten violence* or some sort of legal (including non-government court) action should you copy?