of the person who plucked it, as he has labored to acquire it. He says the "only way, in which ["the wealth of nature"] can be made useful to mankind, is by their taking possession of it individually, and thus making it private property." However, some, such as Benjamin Tucker have not seen this as creating property in all things. Tucker argued that "in the case of land, or of any other material the supply of which is so limited that all cannot hold it in unlimited quantities, these should only be considered owned while the individual is in the act of using or occupying these things." This is a rejection of Absentee ownership for land. Lockean proviso Locke held that individuals have a right to homestead private property from nature by working on it, but that they can do so only "...at least where there is enough, and as good, left in common for others". The proviso maintains that appropriation of unowned resources is a diminution of the rights of others to it, and would be acceptable only so long as it does not make anyone worse off than they would have been before. The phrase "Lockean Proviso" was coined by political philosopher Robert Nozick, and is based on the ideas elaborated by John Locke in his Second Treatise of Government. Criticism Aside from critiques of natural rights as a whole, Locke's labor theory of property has been singled out for critique by modern academics who doubt the idea that mixing something owned with something unowned could imbue the object with ownership: Jeremy Waldron believes that Locke has made a category mistake, as only objects can be mixed with other objects and laboring is not an object, but an activity. Judith Jarvis Thomson points out that the act of laboring makes Locke's argument either an appeal to desert, in which case the reward is arbitrary-"Why not instead a medal and a handshake from the president?"-or little different than first possession theories that existed before Locke. Ellen Meiksins Wood provides a number of critiques of Locke's labor theory of property from a Marxist perspective. Wood notes that Locke is not actually concerned with the act of labor or improving the use value of property, but rather is focused on the creation of exchange value as the basis of property. In addition to the theoretical deficiencies of Locke's theory of property,