Macsnafu, I guess we just differ on that. Let’s say that in order to get any coconuts from the palm trees, you need to build a fence around them so that the island’s crabs don’t come and eat them. While I was asleep, you built such fences around the five trees which you claim to own, thereby mixing your labor meaningfully with them. And because you’re a big eater, and the coconuts are delicious, you’re perfectly able to find uses for all the coconuts you harvest. It still seems to me that at some point, you started encroaching on my fair share of the coconut palms when you were building your fences, and I would be justified in demanding compensation, or some of the trees, or something like that. I admit that exactly what I’d be justified in demanding is unclear. But it seems to me like I’d be justified in demanding something, because your actions just seem unfair. If you don’t share this intuition, then I’d be hard pressed to tell you you’re wrong; it just seems self-evident to me.
Geoffery, in the introduction to what I take to be one of the more significant left-libertarian works in recent memory, Left-Libertarianism and Its Critics: The Contemporary Debate, Peter Vallentyne writes, “Left-libertarian theories of justice hold that agents are full self-owners and that natural resources are owned in some egalitarian manner.” I take that to be the definition of left-libertarianism. That view is somewhat reflected in Roderick Long’s explanation of why he considers himself to be a left-libertarian: “I’ve had some kind words for multiculturalism, postmodernism, political correctness, environmentalism, and collective ownership; and I regard libertarianism as properly rooted in egalitarianism.” Long also writes, however, that he considers himself “90% orthodox Rothbardian” and that he doesn’t approve of Tucker-style or Georgist limits on land ownership. What this means in terms of his accepting Rothbard’s view of just appropriation is unclear. But if we accept the definition of left-libertarianism which (I believe) is used by most people involved in the debate, then it’s as simple as saying “If he believes in some egalitarian principle of appropriation of natural resources, then he’s a left-libertarian; if he accepts Rothbard’s, then he’s not.” I think I’m comfortable with that.
You also write, “On a tiny remote island it might have some plausibility, but in typical society, not to mention a globalized economy, it would seem to be highly implausible to point to someone and say he hasn’t left enough-and-as-good for you. To elevate the plausibility (accepting it for the sake of argument for now) of it being just to expropriate the land appropriated by the one castaway who didn’t leave enough-and-as-good for the other, to elevate it to the level of a principle of justice for a normal society would I think be a monumental mistake, a departure from true justice and libertarianism. It’s a mistake to formulate a general principle for normal social situations from such an extremely irregular case.”
I’m not completely sure how I opened myself up for this objection, because I have intentionally avoided advancing any claim about what kind of principle would be correct. All I said was that in the island case, it seems like “enough and as good” was not left for me, and that seems unfair. Exactly where we should go from there is up in the air; I certainly don’t know what the right answer is. My point is this: if you accept Rothbard’s view of appropriation, then you commit yourself to saying that the outcome of the island example is perfectly fair. It’s my contention that it’s not fair.
The modus tollens structure of the argument is critical; you seem to be attacking me as if I were making a modus ponens argument. My argument is this:
If Rothbard is right, then the island outcome is fair. The island outcome is not fair. Therefore, Rothbard is not right.
It is not:
If principle of justice in appropriation X is right, then Rothbard is wrong. The island example demonstrates that X is right. Therefore, Rothbard is wrong.
Do you see how my argument allows me to avoid defining X, and therefore escapes your repeated objections about my inability to do it?
Thanks for the links to Schmidtz’s work; I’ll check it out when I get a chance. Incidentally, I’m also not sure how much I accept the principle of self-ownership as it’s generally advanced, but I do believe that Cohen was right in saying that libertarianism lives and dies by that principle. I consider myself a libertarian only because I think that the principle of self-ownership could be ammended to better fit our intuitions, and that an overly stringent view of it is commonly taken. But that’s an entirely different conversation.