In the same way, the social conditions of the production of art keep changing. If one looks at cave art, one realises that there is no hard and fast line between the private and public art of the hunting communities that produced it; but certain things emerge in early art that continue through history as characteristics of art.

Art is essentially human expression. Primitive man picked up objects that he felt expressed his being, or tried to draw them with ochre or soot, or gouged them into rocks. The essence of art is human expression. It is human intervention in the environment. Even a found object, like the black stones with white markings, saligrams, rocks of unusual shapes that are enshrined in the rock-gardens of the imperial palace in Beijing, the found objects of Daniel Arp, driftwood sculpture, or even the urinal Marcel Duchamp exhibited as a `Fountain', all have artistic value only because someone has picked them up at some time and felt that these objects embodied what he wanted to communicate to others beyond that moment in time. This spontaneous vindication of every person's expression as a valid part of human expression is the essence of art. It did not, however, come up without a long fight.

For ``undisciplined'' expression has always frightened those who find individual aberrations a threat to their prescription ofwhat should be seen and what should not be seen by society. So, from the earliest times, when humans used leaves, bark and even feathers or skins of animals to cover their genitals, some idea of what can or cannot be conventionally seen has existed in society. These conventions have been changing over time, but they have both a positive and a negative side to them. An appreciation of this is very important for the understanding of art and for the investor to understand what to invest in and what not to invest in.

The positive side of this is simply that every society tries to invent a visual language that is beyond the individual. The symbol and the hieroglyph are the most unimaginative, strict and conventional forms. Where religion and ritual have a stranglehold on art, these forms become stereotypes. We can see this process developing in the art of Ajanta, where the cave of multiple Buddhas is no more than so many stamped images that are exactly the same. Such standardised and unimaginative art has a market, but it is as ritual necessity dictates or as an antique. It is not art in which to invest.

Such visual expression is at its most standardised and conventional in feudal art, where every element of the artist's independent expression was suppressed as far as possible by religious dogma and the feudal lords. An acceptance of this oppression by the artist is reflected in the mistaken belief that artists ought to paint, not think. True, where actors use their voices, writers and philosophers words, artists use their hands to think. But under feudalism, their thinking was strictly regimented and controlled by patrons. Such feudal art was really craftsmanship: conventional, repetitive and decorative.

It took a lot of effort, it was detailed, but the expression of the artist was minimal and the price of such objects too remains at a level far less than that of genuine contemporary art objects. But it does not mean that the feudal artist allowed himself to be willingly suppressed. Take, for example, the Mahabalipuram relief of the Descent of the Ganga. Here, there is a Jataka rendering of a cat doing penance on the banks of the river to catch mice. Such works of irreverence for the feudal order (in this case, a hypocritical priesthood) are works of independent expression in a period when it was hardly allowed, and are, as a result, art worth investing in.

The individual artist really comes into his own with the development of the capitalist society. And contemporary art works command the price they do primarily for the originality of the artist's expression, the novelty of approach, and of course, a relevance beyond the moment. This is the art produced when the market is supreme. The decorative aspect,so important to primitive art, is unimportant. The constraints of religion and lordly patronage are not longer there to inhibit the truthful expression of the artist. That is why the paintings of M F Husain continue to command high prices and the books of Salman Rushdie to be read in greater number than ever before despite attacks on them by religious fanatics and small-time authoritarians.

What is fascinating is how attacks like those on Husain's spontaneous and irreverent art have actually helped to raise the price of his works. In fact, I remember how a particular work of his, which had a gang of Hindu fundamentalists baying for his blood, was bought up by an anonymous buyer almost immediately after the forced closure of the exhibition in which it was shown. It is obvious that originality, innovativeness and irreverence have a lot to do with the success of contemporary art in the market today. If a Van Gogh managed to sell just one work of art in all his life, a man like Andy Warhol made his tongue-in-cheek art a global market success, reflecting the speed with which the market is responding to the creative entrepreneur.

Investment trends in art should not surprise us. They reflect those in all other fields of investment. Innovativeness, originality, novelty and new breakthroughs in communication bring back the best dividends in art as in other fields. Investment in art, like all investment today, reflects the capacity of art to ride the market forces and nothing else. There is nothing mysterious about it. Art, like all human activity, responds to changing socieconomic conditions and to the processes of accumulation, exploitation and investment. So it can be invested in with better returns than many other things.