Briefly, two points from medieval English Law.
From Bracton (13th century), from a section on "What wreck is; and concerning great fish, that is, sturgeon and whale," concerning who can claim shipwrecks or great sea animals that wash up on shore:
If a ship is broken and no living soul escapes from it [de qua nullus vivus evaserit] [,] that may properly be called wreck, especially if the owner has drowned, because the true owner, coming from afar, may prove by certain proofs and signs that the things are his, as where a dog is found alive and it can be established that he is its master; it will be presumed that he is also the owner of the things, and so [also] if certain marks have been placed on the wares and goods.
Further words on wrecks and life from the Statute of Westminster, 1275, c.4, quoted from English Historical Documents III, 398-99:
On wreck of the sea it is agreed that when a man, a dog or a cat escapes alive from a ship, neither the ship nor the boat nor anything that was in them shall be adjudged wreck, but the things shall be saved and kept, by view of the sheriff, the coroner or the king's bailiffs, in the hands of the people of the vill where the goods are found, so that if anyone sues for these goods within a year and a day and can prove that they are his or his lord's, or were lost when in his keeping, they shall be restored to him without delay; and if not, they shall remain the property of the king and be appraised by the sheriff and the coroner and given to the township to answer before the justices for wreck belonging to the king.Classical commentators on English law judge the dog and the cat of the Westminster Statute as only examples, but there's more, much more to be said about forms of witness and recognition: life, not of whatever sort but particularly domestic, attesting to the integrity of a ship; life that we would think of as mere zoe now political life, entering into the law as witness simply by virtue of its own integrity as life; a dog, in the Bracton, as a good witness to claims of human identity (a legal version of a story as old as The Odyssey or as common as The Dog of Antioch).
When can nonhuman life count as significant life? When is its life equivalent to that of a human? When can it give witness? Here I think I have the grounds for a future study.
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