Eigentum über Ideen in Lockes Rahmen (IH)
Justin Hughes, The Philosophy of Intellectual Property
Epstein directly, albeit unknowingly, points out a critical difference: we are not in possession of any particular external objects by a kind of natural necessity. If we were, the need for property laws would be greatly diminished. Each person, like a tree, would be rooted to his own parcel of external objects; this would be "of natural necessity," and no one would try to displace another from his natural and necessary attachments. Precisely because "natural necessity" goes no further than the mind/body link, reliance upon the "possession" of body as a foundation for a possession-based justification of property is a bit disingenuous.
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We can justify propertizing ideas under Locke's approach with three propositions: first, that the production of ideas requires a person's labor; second, that these ideas are appropriated from a "common" which is not significantly devalued by the idea's removal; and third, that ideas can be made property without breaching the non-waste condition. Many people implicitly accept these propositions. Indeed, the Lockean explanation of intellectual property has immediate, intuitive appeal: it seems as though people do work to produce ideas and that the value of these ideas -- especially since there is no physical component -- depends solely upon the individual's mental "work."