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Imagine that Banksy, (or J.S.G. Boggs, or some other artist whose name starts with “B”, and who is known for making fake money) creates a perfectly accurate counterfeit dollar bill – that is, he creates a piece of paper that is indistinguishable from actual dollar bills visually, chemically, and in every other relevant physical way. Imagine, further, that our artist looks at his creation and realizes that he has succeeded in creating a perfect forgery. There doesn’t seem to be anything mysterious about such a scenario at first glance – creating a perfect forgery, and knowing one has done so, although extremely difficult (and legally controversial), seems perfectly possible. But is it?

In order for an object to be a perfect forgery, it seems like two criteria must be met. First of all, the object must be a forgery – that is, the object cannot be a genuine instance of the category in question. In this case, our object, which we shall call X, must not be an actual dollar bill:

1.) X is not a dollar bill.

Second, the object must be perfect (as a forgery) – that is, it can’t be distinguished from actual instances of the category in question. We can express this thought as follows:

2.) We cannot know that X is not a dollar bill.

Now, there is nothing that prevents both (1) and (2) from being simultaneously true of some object X (say, our imagined fake dollar bill). But there is an obstacle that seemingly prevents us from knowing that both (1) and (2) are true – that is, from knowing that X is a perfect forgery.

Imagine that we know that (1) is true, and in addition we know that (2) is true. In other words, the following claims hold:

3.) We know that X is not a dollar bill.

4.) We know that we cannot know that X is not a dollar bill.

Knowledge is factive – in other words, if we know a claim is true, then that claim must, in fact, be true. Applying this to the case at hand, this means that claim (4) entails claim (2). But claim (2) and claim (3) are incompatible with each other: (2) says we cannot know that X isn’t a dollar, while (3) says we know it isn’t. Thus, (3) and (4) can’t both be true, since if they were, then a contradiction would also be true (and contradictions can’t be true).

Thus, we have proven that, although perfect forgeries might well be possible, we can never know, of a particular object, that it is a perfect forgery. But an important question remains: If this is right, then what, exactly, is going on in the story with which we began? How is it that our imagined artist doesn’t know that he has created a perfect forgery?

In order to answer this question, it will help to flesh out the story a bit more. So, once again imagine that our artist creates the piece of paper that is visually, chemically, and in every other physical way indistinguishable from a real dollar bill.  Call this Stage 1. Now, after admiring his work for a while, imagine that the artist then pulls eight genuine, mint-condition dollar bills out of his wallet, throws them on the table, and then places the forgery he created into the pile, shuffling and mixing until he can no longer identify which of the pieces of paper is the one he created, and which are the ones created by the Mint. Let’s call this Stage 2. How do Stage 1 and Stage 2 differ?

At Stage 1 we do not, strictly speaking, have a case of a perfect forgery. Although the piece of paper the artist created is physically indistinguishable from a dollar bill, the artist can nevertheless know it is not a dollar bill because he knows that he created this particular object. In other words, at Stage 1 he can tell that the forgery is a forgery because he knows the history, and in particular the origin, of the object in question.

Stage 2 is different, however. Now the fake is a perfect forgery, since it still isn’t a dollar, but we can’t know that it isn’t a dollar, since we can no longer distinguish it from the genuine dollars in the pile. So in some sense we know that the fake dollar in the pile is a perfect forgery. But we can’t point to any particular piece of paper and know that it, rather than one of the other eight pieces of paper, is the perfect forgery. In other words, in Stage 2 the following is true:

• We know there is an object in the pile that is a perfect forgery.

But the following, initially similar looking claim, is false:

• There is an object in the pile that we know is a perfect forgery.

We can sum all this up as follows: We can know that perfect forgeries exist – that is, we can know claims of the form “One of those is a perfect forgery”. But we can’t know, of a particular object, that it is a perfect forgery – that is, we can never know claims of the form “That is a perfect forgery”. And it is this latter sort of claim – that we know, of a particular object, that it is a perfect forgery – that leads to the contradiction.

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By T. Douglas Price

Science works in mysterious ways. Sometimes that’s even truer in the study of the origins of the human race.

Piltdown is a small village south of London where the skull of a reputed ancient human ancestor turned up in some gravel diggings a century ago. The find was made by Charles Dawson, a lawyer and amateur archaeologist, with an unusual knack for major discoveries. Shortly thereafter a lower jaw that fit the skull turned up and, voilá — the missing link between the apes and man had been found in the British Isles.

The Manchester Guardian headlined “The earliest man? Remarkable discovery in Sussex. A skull millions of years old.” The find was widely regarded as the most important of its time. The discovery of Piltdown Man made Europe, and especially Great Britain, the home of the “first humans”. The find fit the expectations of the time and resolved certain racist and nationalist biases against evidence for human ancestry elsewhere. Early humans had large brains and originated in Europe.

Piltdown Gang by John Cooke (1915). Back row: (left to right) F. O. Barlow, G. Elliot Smith, Charles Dawson, Arthur Smith Woodward. Front row: A. S. Underwood, Arthur Keith, W. P. Pycraft, and Sir Ray Lankester.

For 40 years this Piltdown Man was generally accepted as an important ancestor of the human race. Various authorities raised doubt and critiqued the evidence, but Piltdown kept its place in our early lineage until a curator at the British Museum, Kenneth Oakley, took a closer look. Oakley and several other scientists assembled incontrovertible evidence to the show that Piltdown was a forgery. The chemistry of the jaw and skull were different and could not have come from the same individual. The teeth of the lower jaw had been filed down to make them fit with the skull. The skull was human but the jaw came from an ape. The bones had been stained to enhance the appearance of antiquity. In 1953, Time magazine published this evidence gathered by Oakley and others. Piltdown was stricken from the record and placed in ignominy, a testimony to the gullibility of those scientists who see what they want to see.

Hoax, fraud, crime? Perhaps the designation is not so important, but the identity of the perpetrator appears to be. More than 100 books and articles have been written over the years, trying to solve the mystery of who forged Piltdown. Various individuals have been implicated, but the pointing finger of justice always returns to Charles Dawson. Dawson’s knack for finding strange and unusual things was more than just luck. His sense of intuition was fortified by a home workshop for constructing or modifying these finds before he put them in the ground. A recent book by Miles Russell, The Piltdown Man Hoax: Case Closed, documents Dawson’s numerous other archaeological and paleontological “discoveries” that have been revealed as forgeries. As Russell noted, the case is closed. That fact, however, is not keeping British scientists from throwing a good bit of money and energy into the whodunit, using the latest scientific technology to try to unmask the culprit.

So, 100 years of Piltdown. Not exactly a cause for celebration — or is it? Science does work in mysterious ways. Although Piltdown misled the pursuit of our early human ancestors for decades, much good has come from the confusion. Greater care is exercised in the acceptance of evidence for early human ancestors. Scientific methods have moved to the forefront in the investigation of ancient human remains. The field of paleoanthropology — the study of early human behavior and evolution — has emerged wiser and stronger. The earliest human ancestors are now known to have come from Africa and begun to appear more than six million years ago. Evolution, after all, is about learning from our mistakes.

T. Douglas Price is Weinstein Professor of European Archaeology Emeritus at the University of Wisconsin-Madison. His books include Europe before Rome: A Site-by-Site Tour of the Stone, Bronze, and Iron Ages; Principles of Archaeology; Europe’s First Farmers; and the leading introductory textbook in the discipline, Images of the Past.

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As we journey farther into the New Year, we’ve been reflecting on all the wonderful books published in 2010, and in doing so, we’ve also realized there are some classics worth revisiting. The authors and friends of Oxford University Press are proud to present this series of essays, drawing our attention to books both new and old. Below, Anatoly Liberman (the Oxford Etymologist) encourages us to read The Portrait of Mr. W.H.

By Anatoly Liberman

Oscar Wilde is most often quoted for his infinite wit, and those who know him are mainly aware of his comedies.  Some people are still charmed by his fairy tales (“The Happy Prince” and a few others; you should have seen how my undergraduate students – those poor products of popular culture – listen to this story!) and cannot shake off the attraction of The Picture of Dorian Gray.  But usually he is mentioned, if at all, in the context of his innumerable mannerisms, the overblown cult of the beautiful, homosexuality, and tragic imprisonment.  The Ballad of Reading Gaol is a famous title, but I wonder who reads the poem today.  More than anything else, Wilde wanted to sound brilliant, which did not cost him the least effort, because he was brilliant.  His paradoxes have become proverbial. In the form of hundreds of familiar quotations they serve as epigraphs to articles and books by our contemporaries—an incautious idea, for beside such an epigraph the rest looks pitifully ordinary.  Deafened by a cascade of paradoxes or touched to tears by sentimental dramas, even some of Wilde’s admirers did not notice that their favorite author was one of the cleverest men in the history of English letters.

My never-ending attempts to translate Shakespeare’s sonnets into Russian have recently returned me to many works I read years ago and remembered but dimly. One of them was Wilde’s essay The Portrait of Mr. W.H. It is a “novella” about the enigmatic man whom Shakespeare or his publisher called the only begetter of the sonnets.  There have been countless attempts to discover the “beauteous youth,” Shakespeare’s main addressee.  All of them failed, but it is obvious why Oscar Wilde was intrigued by the figure of the young man, the “master-mistress” of Shakespeare’s passion, the lord of his soul.  I could repeat the main line of Wilde’s reasoning, but over the years the details have faded from my memory, and now that I know so much more about the sonnets and about those who tried to read them like Shakespeare’s diary than I knew decades ago, I am immediately struck by the ingenuity and elegance of Wilde’s reconstruction.  He was familiar with all the important publications on the sonnets and studied them from the original editions.  With his photographic memory, he, most probably, knew all 154 of them by heart.  His arguments are irresistible.  Of course, Shakespeare told us that the youth’s name was the same as his, that is, William, but from lines like “a man in hue, all men in hues controlling” Wilde concluded that the lover’s name was Willie Hughes, a boy-actor in Shakespeare’s company.

However, The Portrait of Mr. W.H. is a story with its own plot.  It is about two people who hope to find some evidence that Willie Hughes existed.  Then suddenly the young man’s portrait turns up, but it is a forgery produced under the most bizarre circumstances by the investigator himself, to convince his friend!  The quest kills both men; yet they did not live for nothing.  We are in the world of Oscar Wilde in which art is more precious than reality, for reality can only imitate art.  No sacrifice is great enough if it is made for art’s sake.  The deadly spirit of make