If we say all markets in all economies are constructs of human culture, therefore by definition we can say they can not determine an a priori objective value for any commodity. So we might say they can accurately find workable prices for goods and services, but that is not the same thing. (See price vs worth vs value )
In short, we can see that prices are determined by the opinions of individuals. These opinions are therefore subjective. A sensible position is that although aggregating those opinions can correct for their errors, it can also magnify those errors. And going from one subjective opinion to a collective subjective opinion does not change this.
In fact, we can say subjective economic perceptions (well founded or not) can often becomes indistinguishable from economic reality, simply by existing. Real estate prices rise or fall (often quite sharply) based on the fact that people think they will rise or fall. The rumor becomes solidified and substantiates itself into an actual price. So prices are subjective, and subject to too many influences from too many people to be otherwise.
From the viewpoint of the individual, another way to see this is as a problem of epistemology. Even if we assume that prices have an objective (not subjective) meaning, that meaning can be too elusive or too quickly shifting for an individual to make use of without the support of an elaborate context.
So for example, it would be impossible for any one person to obtain and digest all the information available about any good-sized market on a given day. To act sensibly in that market we have to specialize, and learn to trust the judgment of others. Everyone, even the people buying and selling the goods and services we depend on (and therefore setting their prices) are doing the same thing.
What people may think of as objective economic facts we can see are actually data from a series of culturally established shortcuts, ways for us to use information gathered and digested by others. This data can be communicated to individuals in countless ways – government reports, news items, statistical fragments, company statements, ads, gut feelings, rumors, discussions with friends, examples from people we trust – and some more reliable than others. Therefore we can say that people absorb and evaluate this mass of stuff, combining it with their own perspectives (however they were established) before making (possibly unconscious) decisions.
Maybe as economic animals people operate in this environment easily enough to take it for granted. And it seems to work, well enough - things get bought and sold, people work and get paid, problems show up and (we hope) are fixed.
But overall it seems surprising the degree to which they trust all this subjective data. For example, although people might like to think that when a large sum of money is at stake in a stock market, reliable information would be required for decision-making. But the actual truth may be that in an effort to get data before anyone else, players in those markets come to rely on unsubstantiated information.
As the Wall Street saying goes, buy on the rumor and sell on the news. In other words, if a rumor is going around that a stock is going to rise because of some announcement by the company, buy before the announcement because waiting until the information is confirmed means acting too late to make a profit.
So again, we return to a state of epistemological uncertainty – we can never be truly sure of where prices in a market should be in an absolute sense. Since the market is itself a social construct, thinking there can be some a priori reality found through a market pricing mechanism is absurd.
But while we can’t be sure what a price should be, we can be sure of what it is. The entire mechanism of pricing (putting monetary numbers on the worths of things) exists so we can be certain. When something is bought and sold at a particular price, no matter the thing and no matter the price, we as a society have just taken a snapshot of a transaction – a record of a moment, which can be used as a reference point.
And this could be said to be the strength of the system, because that bit of freeze dried information is compared with others just like it, and the feedback from the comparison is also put in the mix. It may be one data point, but it’s part of a series. Which returns us to the notion of a market as collective subjective action. And also in an interesting way, to the notion of a market as a form of human culture.
Buying and selling require two or more people. This means setting a successful price is an inherently social act. The people involved may lie and they may withhold information, but the parties in the transaction have to reach a fixed price point or the transaction is meaningless. It doesn’t take place.
By using numbers to demarcate patterns in a constantly shifting dynamic system, in our theory the price setting mechanism comes to resemble the evolutionary metaphysics described by Robert Pirsig in his novel Lila
In this context, consider the limits to how reliable data from even a large collective subjective can be. Groups of individuals can shift erratically, which is why early economists often found themselves looking to the literature on the behavior of crowds when trying to explain financial panics.
This could help explain the irreducibly non-rational elements in the behavior of markets. we can say they are the results of some important components - the human beings.
But we say the value of the goods and services to those human beings is the key – an economy grows by adding value, and it adds value from the viewpoint of individuals.