“An old and much respected theory holds that for a man to come into possession of a previously unowned value it is necessary for him to “mix his labor with the land” in order to make it his own. But this theory runs into difficulties when one attempts to explain what is meant by “mixing labor with land.” Just how much labor is required, and of what sort? If a man digs a large hole in his land and then fills it up again, can he be said to have mixed his labor with the land? Or is it necessary to effect a somewhat permanent change in the land? If so, how permanent?..Or is it necessary to effect some improvement in the economic value of the land? If so, how much and how soon?..Would a man lose title to his land if he had to wait ten months for a railroad line to be built before he could improve the land?..And what of the naturalist who wanted to keep his land exactly as it was in its wild state in order to study its ecology?..[M]ixing one’s labor with the land is too ill-defined a concept and too arbitrary a requirement to serve as a criterion of ownership”. Market For Liberty
It seems to me that they are simply asking the wrong question. For example, you would never argue that labor is too ill-defined for exchange of a good owned by someone. The labor is defined clearly by the terms of exchange. Yet, to ask how much labor should you exchange for something no one owns is silly. There are no terms, you take the property based on whatever amount of labor you deem necessary. You may climb a tree for a banana or cut down the tree for the banana, you may ignore the tree or you may destroy the tree. Why are we speaking about “how much” land and labor to mix when “how much” presupposes there is a barter of terms of exchange. So unless the man is bartering with his other personality or with a ghost, he need not barter very long with the tree before he does what he wills.