The bit that c-law and others are missing is that there is something of a gold-bug angle to pricing "fine arts" as well: Why is it expensive? It's expensive because investors see it as a store of value!
As to the rest of the argument, I think I hold some common ground with Orion in saying that we can distinguish different reasons for holding a piece of artwork to be valuable than somebody else - and we can judge them superior to others (though I would suggest avoiding this, as I will explain at the end). Perhaps part of the answer why "modern art" values are so disjoint from "common sense" artistic sense is the result of the modern (i.e., post-Revolutionary France) dislocation from and an apparent destruction of notions of value - i.e. the notion of absolute bases for morals (dead along with God, according to one worldview), or the worth of traditional subjects for fine art to commemorate or extol the virtues of the benefactor (Papist or Medici; elector or local clergy); this follows Hans Sedylmayr's 1948 work "Art In Crisis," which seems better described by its original title "Loss of the Center," speaking of Germans and name-dropping).
It would be disingenuous to say that modern art is all characterized by the attitudes of pernicious territoriality, or that artists are unconcerned with content (it would be fair to say, however, that it is characterized by the tension between content and form, e.g. the poet's attention to sound and pattern on the one hand, and on promoting their ideas on the other - and the only time it seems warranted to denounce an artist's particular balance is when they have put their art in service of something we dislike, which of course is an argument unrelated to the form and content). Just as Sedylmayr finds that there is a "loss of the center," from the time he examined right up to the present one also finds reason to be critical of authority figures. In its simplest form, the question becomes: If I am sending a message through my work, whose will it be? So phenomena like the "Rape Tunnel" and the proliferation of content-free images are probably less myopic and navel-gazing, in one sense, than they seem.
On the other hand, I think it is definitely fair game to turn the question around: By declaring war on all content, how do many artists and their modern heralds admit that the extremes of morals-expunged or morals-laden works have anything left to do with art?
Oscar Wilde's "The Decay of Lying" provides multiple answers to the questions, but chief amongst these is that life imitates art (it might help to think of this in the sense of things attempting to become perfect, or to approximate a Platonic ideal, although I do not want to get Plato into this beyond his notion of an ideal plane of existance, which Art most closely approximates), and that Art exists for its own sake.
In putting content-free, or morality-laden, artworks up as the ideal, artists and their owners (not a typo) have essentially returned to nature, creating dim, warped images of nature, rather than pure ideals which go farther than nature.
Although Wilde's piece is not clearly wholly serious, I think even he would nod in consternation at how far the market for artworks has diminished the position of artistic content.
For the chief value of an expensive photograph, or a painting, coin, or hand of dirt or anything, is its market value, so we are told and constantly reminded by the endless printing of headlines heralding a "new record set at auction." The wealthy investor-buyer of an artwork (who, it should be noted, is partly to blame for the increasing prices of "classic" artworks which most of us would consider simply invaluable) does not need to care an iota about the content, but rather is trying to predict the whims of the market. A particularly scathing piece about the vacuousness of a certain photographer's works might end up merely furthering the notoriety of that piece. The fine arts market is in a classic bubble, but it does not appear to be a bubble because so far the wealthy have not been asked or forced to put priority in creating a broad base of wealth, nor have any of the other typical restraints worked to deflate a market whose chief value is its very impracticality. To the ideal of equality, the wealthy pay lip service; in practice, they seek ever more unassailable and intangible constructions of wealth, and pack their cherished collections off into vaults never to be seen again. Ironically, more practically invested this money would have a tangible salutary effect on the wealthy as well as on everyone else, but jealousy prevents them from seeing the potential to lift everyone together.
The corrupting effect this mentality has on society takes many, and surprising forms, but of the true and unchanging value of artworks - the persistence and survival of a superior idea or ideal - is something that is not reflected in a balance ledger. You either "get" an argument or an artwork, or you do not.
As the Bible recommends us to remember, silver tarnishes and tapestries become moth-eaten. Even so, some people who profess themselves ardent Christians still promote a return to the Gold Standard, in the idea that - rather like the clueless art buyer at auction - gold itself has some inherent monetary value. What is the inherent value of gold? Its inherent value is its value, apparently.
For the wealthy, inflation is a chief evil; for the poor, unemployment is. (See William Jennings Bryan and his "Cross of Gold" speech - just the synopsis will explain it). Do not be fooled into thinking that the "value" at auction of an artwork as a wealthy man's hedge against inflation is at all related to its utility or durability as a popular meme or a useful idea. Somebody might try to trademark or get wealthy off other peoples' pictures of dogs with funny hats on their heads, or cats asking if they can haz cheezburgers, but the real value is not money - it's that common element. It doesn't matter if Socrates or Aristotle didn't have as good a hedge for their earnings as somebody else - we still remember them after more than two thousand years.
OK, so what IS a good reason for valuing an artwork? Indeed, the context matters
for some people. But the context of a dead-ended intellectual dating game is meaningless for anybody not in on that little secret, as well. Ultimately, I think that what we value in an artwork is what we value as rational human beings: The ability of a work to espouse the ideals we subscribe to. For the superrich, that may be context-free photographs of alternating blue and green stripes, which are as unable to evoke sympathy for the poor as they are unable to condemn the misappropriation of our public debate over the proper role of government. For everyone else, that may be the hard-fought distinction to be somehow remembered after one's death without the benefit of public trusts in your name.
(Of course, you might notice that I've somewhat sidestepped c-law's central point, which is that there is a monolithic school of thought on photography - nonense. If some people calling themselves Germans have been bowed over by the wishes of wealthy investors or institutions, that does not diminish the very public role of contrarian viewpoints in shaping the public acceptance of photographs - for every esoteric mention of one school or another, one properly positioned book or article might turn the discussion in a different direction - like here
, for instance. As far as I can distinguish it, the argument that the DÃ¼sseldorf school seems to promote is that fame can be arbitrary - which of course is either an abandonment of Art's potential for content, or it is an implicit attack on the idea of merit by means other than worth - since the members of the DÃ¼sseldorf school will happily take your money, no matter where you come from; therefore it is suddenly Art which is left without a defender. Both readings smell strongly of apathy to me; that might agree with Wilde's piece above, but please consider where his political apathy got him.)