The Philosophy of Law: Private Right, § 39: The Revindication of What Has Been Lost
It is clear from what has been already said that ;i Thing of mine which continues to exist, remains mine although I may not be in continuous occupation of it; and that it does not cease to be mine without a Juridical Act of dereliction or alienation. Further, it is evident that a Right in this Thing (jus reale) belongs in consequence to me (jus personate), against every holder of it, and not merely against some Particular Person. But the question now arises as to whether this Right must be regarded by every other person as a continuous Right of Property per se, if I have not in any way renounced it, although the Thing is in the possession of another.
A Thing may be lost (res amissa), and thus come into other hands in an honourable bond fide way as a supposed ‘Find;’ or it may come to me by formal transfer on the part of one who is in possession of it, and who professes to be its Owner, although he is not so. Taking the latter case, the question arises, Whether, since I cannot acquire a Thing from one who is not its Owner (a non domino), I am excluded by the fact from all Right in the Thing itself, and have merely a personal Right against a wrongful Possessor? This is manifestly so, if the Acquisition is judged purely according to its inner justifying grounds and viewed according to the State of Nature, and not according to the convenience of a Court of Justice.
For everything alienable must be capable of being acquired by any one. The Eightfulness of Acquisition”, however, rests entirely upon the form in accordance with which what is in possession of another, is transferred to me and accepted by me. In other words, rightful Acquisition depends upon the formality of the juridical act of commutation or interchange between the Possessor of the Thing and the Acquirer of it, without its being required to ask how the former came by it; because this would itself be an injury, on the ground that Quilibet prccwmitur bonus. Now suppose it turned out that the said Possessor was not the real Owner, I cannot admit that the real Owner is entitled to hold me directly responsible, or so entitled with regard to any one who might be holding the Thing. For I have myself taken nothing away from him, when, for example, I bought his horse according to the Law (titulo empti venditi) when it was offered for sale in the public market. The Title of Acquisition is therefore unimpeachable on my side; and as Buyer I am not bound, nor even have I the Right, to investigate the Title of the Seller; for this process of investigation would have to go on in an ascending series ad infinitum. Hence on such grounds I ought to be regarded, in virtue of a regular and formal purchase, as not merely the putative, but the real Owner of the horse.
But against this position, there immediately start up the following juridical Principles. Any Acquisition derived from one who is not the Owner of the Thing in question, is null and void. I cannot derive from another anything more than what he himself rightfully has; and although as regards the form of the Acquisition—the modus acquirendi—I may proceed in accordance with all the conditions of Right when I deal in a stolen horse exposed for sale in the market, yet a real Title warranting the Acquisition was awanting; for the horse was not really the property of the Seller in question. However I may be a bond fide Possessor of a Thing under such conditions, I am still only a putative Owner, and the real Owner has the Right of Vindication against me (rem suam vindi-candi).
Now, it may be again asked, what is right and just in itself regarding the Acquisition of external things among men in their intercourse with one another—viewed in the state of Nature—according to the Principles of Commutative Justice? And it must be admitted in this connection, that whoever has a purpose of acquiring anything, must regard it as absolutely necessary to investigate whether the Thing which he wishes to acquire does not already belong to another person. For although he may carefully observe the formal conditions required for appropriating what may belong to the property of another, as in buying a horse according to the usual terms in a market, yet he can, at the most, acquire only a Personal Right in relation to a Thing (jus ad rem) so long as it is still unknown to him whether another than the Seller may not be the real Owner. Hence, if some other person were to come forward, and prove by documentary evidence a prior Right of property in the Thing, nothing would remain for the putative new Owner but the advantage which he has drawn as a bond fide Possessor of it up to that moment. Now it is frequently impossible to discover the absolutely first original Owner of a Thing in the series of putative Owners, who derive their Rights from one another. Hence no mere exchange of external things, however well it may agree with the formal conditions of Commutative Justice, can ever guarantee an absolutely certain Acquisition.
Here, however, the juridically law-giving Reason comes in again with the Principle of Distributive Justice; and it adopts as a criterion of the Rightfulness of Possession, not what it is in itself in reference to the Private Will of each individual in the state of Nature, but only the consideration of how it would be adjudged by a Court of Justice in a Civil state, constituted by the united Will of all. In this connection, fulfilment of the formal conditions of Acquisition that in themselves only establish a Personal Right, is postulated as sufficient; and they stand as an equivalent for the material conditions which properly establish the derivation of Property from a prior putative Owner, to the extent of making what is in itself only a Personal Right, valid before a Court, as a Peal Right. Thus the horse which I bought when exposed for sale in the public market under conditions regulated by the Municipal Law, becomes my property if all the conditions of Purchase and Sale have been exactly observed in the transaction; but always under the reservation that the real Owner continues to have the Right of a claim against the Seller, on the ground of his prior unalienated possession. My otherwise Personal Right is thus transmuted into a Real Right, according to which I may take and vindicate the object as mine wherever I may find it, without being responsible for the way in which the Seller had come into possession of it.
It is therefore only in behoof of the requirements of juridical decision in a Court (in favorem justitice distribu tives) that the Right in respect of a Thing is regarded, not as Personal, which it is in itself, but as Real, because it can thus be most easily and certainly adjudged; and it is thus accepted and dealt with according to a pure Principle & priori. Upon this Principle various Statutory Laws come to be founded which specially aim at laying down the conditions under which alone a mode of Acquisition shall be legitimate, so that the Judge may be able to assign every one his own as easily and certainly as possible. Thus, in the brocard, ‘Purchase breaks Hire,’ what by the nature of the subject is a Real Right—namely the Hire—is taken to hold as a merely Personal Right; and, conversely, as in the case referred to above, what is in itself merely a Personal Right is held to be valid as a Real Right. And this is done only when the question arises as to the Principles by which a Court of Justice in the Civil state is to be guided, in order to proceed with all possible safety in delivering judgment on the Rights of individuals.