A couple of responses to a couple of points made.
On the argument that there are more serious problems in the world, so let's not get too worked up about a few cds - agreed, within limits.
To me, the limit is obvious: I either can't or won't do anything about some big moral issues. That doesn't excuse me from small moral issues that come along.
As to why a library can lend out a book or cd: only one person at a time has use of the item, assuming he doesn't make a copy.
The general ethical rule, I think, is - if you're not creating a copy for another party's use, you're ok.
So if I buy a cd and loan it to a friend, I'm fine. If I make a copy first for my own use, I'm not.
Can this get to absurd tiny slices fast? Yep. But just because it can get silly, it doesn't mean you can treat the larger question as unimportant - especially if you're deeply committed to music and musicians.
Finally, a comment: I'm no lawyer, but in my view the act we're talking about here is *not* stealing.
It's more in the realm of violating a civil contract between you and the record company, and should be settled without the moral panic the record companies attach to this issue.
In my opinion, this has never *really* been about casual copying. I believe the record companies' real point was to use the moral panic to impose air-tight use restrictions, so that you had to pay a fee to listen to the item at home, another one to listen in your car, a third for use on your iPod, etc.
If you think this is silly, consider what's going on in the motion picture industry, where you now get 'free' copies of the movie - along with the dvd - to play on your portable player. In fact, the newly reissued dvds with the digital copies are slightly more expensive than the copies they replace.
So to bring it all back around - the reason to not sell the cds you've made copies of is to be ethically ok yourself, and not because you like/respect/have sympathy for the majority of the audio industry.
Scott A.