According to a new historical study, we know ourselves by the papers we keep.

"All written forms for registering identification (lists, wanted circulars, descriptions) faced the same dilemma: what was committed to writing was immutable, whereas the person described continued to change, not least through the process of registration itself: once a personal description was out in a search warrant, that person had to change."

Who Are You? offers some fascinating historical tidbits. It briefly touches on the famous story of the con artist Arnaud du Tilh who "passed himself off as the absentee soldier-adventurer Martin Guerre, taking his place as a returnee to Guerre's village and marriage bed." We learn that the identification of dead soldiers -- especially when searching for one's slain leader -- was difficult because the victors would always strip the clothes and weapons from already battered bodies. In the Middle Ages the Gypsies were the equivalents of our illegal immigrants. They eventually fell into a double bind that still makes perfect bureaucratic sense:

"The imperial jurists drew a remarkable conclusion from the longstanding and largely unsuccessful endeavor to curb and monitor the movement of Gypsies in the different parts of Europe and to dispose of such undesired traveling people. The royal order of 1551 and subsequent regulations obliged all authorities to confiscate and destroy all letters of conduct and identification documents that Gypsies produced. So deceitful were these people, according to the jurists, that any documents they carried had to have been forged. In short, the authorities refused to recognize papers bearing their own signs and marks."

During the 16th century -- an age of "dissimulation," according to Montaigne -- governments increasingly strove to "register everyone and everything." But what was the historical outcome? "The rise of the con man and the impostor, together with their official counterparts, the diplomat and the spy equipped with authentic counterfeit papers. Their careers in dissimulation took place not in spite of, but through the expanding systems of bureaucratic control." Before long, "the scribes of early modern Europe produced mountains of paper abounding with forged attestations, false details, and invented names."

Why was such documentation so important to governments? For the same reasons it is today. In 1796, the German philosopher and historian Johann Gottlieb Fichte wrote:

"The chief principle of a well-regulated police state is this: That each citizen shall be at all times and places . . . recognized as this or that particular person. No one must remain unknown to the police. This can be attained with certainty only in the following manner. Each one must carry a pass with him, signed by his immediate government official, in which his person is accurately described. . . . No person should be received at any place who cannot thus make known by his pass his last place of residence and his name."

Whether you are offended or comforted by such practices, their effectiveness has always been questionable. As Groebner stresses, "surveillance achieves its effects not through administrative perfection, but through arbitrariness, unpredictability, intimidation, and particularly through the collaboration of neighbors and selfish informers." That hardly seems the kind of culture most of us long for. So it's both reassuring and disturbing to be reminded how flawed the system can be. Near the end of Who Are You? Groebner relates a modern story that is, in some ways, a counterpart to that of Manetto, the fat woodworker.

"Identification," Groebner first reminds us, "means presentation" and then asks us to look at the illustration of a modern passport, complete with photograph and stamps.

Its owner "was obliged to present his identity papers at several embassies and border checkpoints. In 1998 he applied for an Austrian tourist visa for three months, then for its Swiss counterpart, which was also valid for three months, and finally for a German one. He looks respectable in the photograph, doesn't he? So does his passport, complete with its official registration number in the top left corner and the signature of the passport officer certifying the document in the bottom right. The document bears security marks in the shape of small keys, as well as the 'Seal of Authenticity' imprinted in numerous places, reassuring us that the seal is 'secure' and 'valid,' embellished by signatures. In medieval categories, this document refers to itself in a most eloquent manner. Its holder was granted the visa for which he applied and subsequently toured Germany, Austria, and Switzerland unhindered for nine months. I hope he enjoyed himself, because it wasn't until he presented himself at passport control in the Zurich airport that an official noticed that 'British Honduras,' the state that had allegedly issued the document, does not exist."

Currently, Groebner notes, efforts are underway to develop unfoolable methods for documenting who we are. So far, the equipment for these has proved unreliable, and the systems readily tricked. As recently as 2002, "facial recognition systems and iris scans were duped by photographs, and fingerprint scanners accepted reproductions made with the aid of cellotape and gelatin."

Groebner closes by underscoring that "identity constitutes the attempt to control how others define us." Social inequities are thus part of this history, too. In his early chapters he discusses what "complexion" means in a description, notes that the wealthy and VIPs have long swanned through checkpoints while the rest of us waited impatiently in long lines, and reminds us that "those whose rights are safeguarded dispose of much greater liberties in their self-representation and their social role playing than groups with lower social status."

All too often, in fact, "identification as surveillance means putting the person being checked in a position where he or she has already done wrong, only to feel obliged to conceal or make up for the contravention. . . . Some aspects of how European countries deal with illegal immigrants today bear witness to the longevity of this principle. Their passports are of little use to them, however genuine they are. They are identified only in order to expel them again as illegal subjects."

In Who Are You? Valentin Groebner shows us that the surveillance and security culture of the 21st century has a long history, as does that of its counterculture of fakes, forgeries and impostors. According to Groebner, you can now buy a high-quality counterfeit U.S. residence permit for around $10,000 on the black market.·

Michael Dirda's e-mail address is mdirda@gmail.com.