It's ok to kill intruders... but it's not ok to enslave them. For some reason this seems a bit... strange. I'm not exactly sure why though. Maybe it's because it doesn't seem like a significant amount of slaves have committed suicide. Evidently slavery was preferable to death in most circumstances.
I'm going to blame John Locke for this line of thinking. A while back I read The Two Treatises of Civil Government. I can't remember exactly what he wrote but it was something about it being acceptable to enslave anybody who attacks you. For some reason this struck me as fairly reasonable. If it's acceptable to kill your attacker... then it would seem acceptable to enslave them. Just like if it's acceptable to use a real gun then it should be acceptable to use a stun gun.
Personally, if I broke into somebody's home and the owner gave me the choice between death and slavery... I think I'd want to know what the slavery would entail. Wouldn't you? Or perhaps you would shout... "Give me liberty or give me death!"
I'm hardly a scholar of slavery but I'm under the impression that it's a continuum. The issue is how much control you personally have over your resources (broadly defined). I think 100% slavery is virtually impossible. For all intents and purposes you'd be a perfect marionette. Even your thoughts would be controlled by your owner. I think that 0% slavery is virtually impossible as well. I don't think you can have perfect control over your resources.
What percentage slavery would prisoners be considered? Or soldiers? Should people have the freedom to sell themselves into slavery? I think so. One argument that I've heard against it is that people might regret their decision. Well... then people shouldn't have the freedom to join the military. Plenty of people have really regretted joining the military. A few have regretted it so much that they've committed suicide.
The problem with unjustified slavery is that it diminishes difference. Less difference means less progress.
