the sea for those who are being tossed upon it, the shore for those who have been cast thereon’. Vergil also says that the air, the sea, and the shore are open to all men.

These things therefore are what the Romans call ‘common’ to all men by natural law,[71] or as we have said, ‘public’ according to the law of nations; and indeed they call their use sometimes common, sometimes public. Nevertheless, although those things are with reason said to be res nullius, so far as private ownership is concerned, still they differ very much from those things which, though also res nullius, have not been marked out for common use, such for example as wild animals, fish, and birds. For if any one seizes those things and assumes possession of them, they can become objects of private ownership, but the things in the former category by the consensus of opinion of all mankind are forever exempt from such private ownership on account of their susceptibility to universal use; and as they belong to all they cannot be taken away from all by any one person any more than what is mine can be taken away from me by you. And Cicero says that one of the first gifts of Justice is the use of common property for common benefit. The Scholastics would define one of these categories as common in an affirmative, the other in a privative sense. This distinction is not only familiar to jurists, but it also expresses the popular belief. In Athenaeus for instance the host is made to say that the sea is the common property of all, but that fish are the private property of him who catches them. And in Plautus’ Rudens when the slave says:[72] ‘The sea is certainly common to all persons’, the fisherman agrees; but when the slave adds: ‘Then what is found in the common sea is common property’, he rightly objects, saying: ‘But what my net and hooks have taken, is absolutely my own’.