Thirdly, in order to render a social construction possible on this basis, we must assume that the right to Freedom includes the right to limit one’s freedom by contract; and that such contracts, if they are really voluntary and not obtained by fraud or force, and if they do not violate the freedom of others, are to be enforced by legal penalties. But I cannot see that enforcement of Contracts is strictly included in the notion of realising Freedom; for a man seems to be most completely free when no one of his volitions is allowed to have any effect in causing the _external_ coercion of any other. If, again, this right of limiting Freedom is itself unlimited, a man might thus freely contract himself out of freedom into slavery, so that the principle of freedom would turn out suicidal; and yet to deduce from this principle a limited right of limiting freedom by contract seems clearly impossible.[213] But if it be difficult to define freedom as an ideal to be realised in the merely personal relations of human beings, the difficulty is increased when we consider the relation of men to the material means of life and happiness. For it is commonly thought that the individual’s right to Freedom includes the right of appropriating material things. But, if Freedom be understood strictly, I do not see that it implies more than his right to non-interference while actually using such things as can only be used by one person at once: the right to prevent others from using at any future time anything that an individual has once seized seems an interference with the free action of others beyond what is needed to secure the freedom, strictly speaking, of the appropriator. It may perhaps be said that a man, in appropriating a particular thing, does not interfere with the freedom of others, because the rest of the world is still open to them. But others may want just what he has appropriated: and they may not be able to find anything so good at all, or at least without much labour and search; for many of the instruments and materials of comfortable living are limited in quantity. This argument applies especially to property in land: and it is to be observed that, in this case, there is a further difficulty in determining how much a man is to be allowed to appropriate by ‘first occupation.’ If it be said that a man is to be understood to occupy what he is able to use, the answer is obvious that the use of land by any individual may vary almost indefinitely in extent, while diminishing proportionally in intensity. For instance, it would surely be a paradoxical deduction from the principle of Freedom to maintain that an individual had a right to exclude others from pasturing sheep on any part of the land over which his hunting expeditions could extend.[214] But if so can it be clear that a shepherd has such a right against one who wishes to till the land, or that one who is using the surface has a right to exclude a would-be miner? I do not see how