THERE IS no truer maxim than “beauty is in the eye of the beholder”.

After all, whether something or someone is considered beautiful is a matter of opinion and even if there is a general consensus on the beauty of a person or object, there will always be someone who disagrees.

But can the same be said of a work of art? And does it have to be beautiful to be valuable?

It’s often said art is only worth what someone is willing to pay for it but that’s certainly not true of everything in life; you might, for instance, only be willing to pay half of what a dealer is asking for a new car but you certainly won’t get it for that price.

So why is art so expensive? And why is one painting worth more than another?

Later this month, a work by Bradford-born David Hockney is expected to smash the previous record price for his paintings when it goes up for auction at Sotheby’s in New York.

Regardless of whether a consensus finds the 10ft-wide work – Pacific Coast Highway and Santa Monica – beautiful or fascinating or moving or inspirational or, as Sotheby’s describes it, “an exuberant monumental landscape”, the art world has decreed it is going to sell for up to 30 million dollars.

The current record price for a Hockney is 11.7 million dollars, paid for Woldgate Woods, an East Yorkshire scene, in 2016.

To many, 30 million dollars (about £22 million) will seem like an obscene amount of money, especially to those scratching out an ordinary living in Hutton Terrace, Eccleshill, where the Hockney family lived for about 50 years. Whether your background is working class, like Hockney’s, middle or upper class, there’s a lot you could do with £30 million which would be likely to take precedence over buying a painting.

Of course, that figure is dwarfed by the £342 million paid in 2017 for the most expensive painting in the world, Leonardo da Vinci’s Salvator Mundi (Saviour of the world). It’s likely Mr Hockney would agree that he’s not in the same class as da Vinci but why would anyone spend such a vast amount of money on a painting when they could build several average-size NHS hospitals for the same sum?

Economists say that the price of art is down to supply and demand. Unlike many commodities, no-one actually needs art but the demand comes from the fact that many people simply want to own fabulous works of art.

The supply side comes into it because all the great artists are dead and, therefore, their paintings are scarce; Rembrandt, Picasso, Canaletto and the like won’t be producing any more work.

But Hockney, of course, is a living artist and a prolific one at that; he has produced a vast catalogue of work covering paintings, drawings, prints, photographs, set design and even iPad sketches.

Supply and demand comes in here as well because each piece of art is unique and once an artist has achieved a certain level of perceived significance, someone will always want an original.

And it is the business of art which really creates demand. Art dealers, gallery owners, museum curators and even the artists themselves help to create the market through promotion of their works. Art professionals set the trends by publicising what they believe is good art and making it clear whose work is likely to appreciate.

According to the Economist magazine, the art market as we know it today has been around since the 18th century and has grown to enormous proportions; in 2015 it was estimated to be worth almost £50 billion pounds – bigger than the whole economy of some countries.

The independent data-analysis website Priceonomics.com says the art market is “controlled by galleries and dealers who commit with astonishing discipline to keeping artwork prices predictable and pegged to signals of quality like the prestigiousness of the gallery selling the artist’s work. You could say the market for art is ‘rigged’; a more charitable explanation is that galleries and dealers act as tastemakers, deciding which art is good and therefore expensive. The end result is to turn artists into brands, which introduces enough certainty for the market to function.”

And the whole art market is propped up by the rich who not only compete to own the most fashionable new art, as well as great masterpieces, but also to access a glamorous lifestyle of art fairs, auctions, glamorous parties and other events where conspicuous wealth is the only entry requirement.

Meanwhile, the Hockney “brand” has been peaking since just before his 80th birthday. Artnet.com, the leading online resource for art experts, says more than half of Hockney’s top auction prices have come since 2015.

Michael Macaulay, of Sotheby’s New York, told the website: “Since the beginning of 2012, 23 Hockney works have been offered for over 500,000 dollars and only three have failed to sell. That success rate for top-level works is rare even for a major artist.

“Collectors love his work in a way that is rare even among the best contemporary artists, so there’s a fairly restricted supply of his work on the market, and huge demand when a major piece comes up.”