In a response to a forwarded post, a friend made the following argument (I am putting only its essence and in my own words, since I have not taken permission to make it public)
Market forces can produce outcomes that are worse off for everyone in the system. A social planner can, (in some cases at least) improve on the efficiency of the market. Pigouvian tax is an example.
In his response, he acknowledges that it might be difficult in practice for the social planner to obtain all the information required, but says that it would be very surprising if the social planners actions could never lead to efficiency improvement.
Consider the crux of the argument (emphasized above). There are three aspects to it that should be considered.
1) What are market forces? They are an abstraction that refers to all the judgements made by individuals interacting with each other under some conditions. If one is talking of a free market, these conditions are the absence of any coercion. Note that for the concept of coercion to be clear, a system of property rights (at the very least) needs to be in place (More on this in 3). If one is to prove the statement above (in a mathematical sense, which is what my friend meant), these market forces need to be modeled. This leads to 2.
2) How are choices evaluated? In actuality, every individual evaluates and weighs choices in a unique manner depending on the context of his knowledge, his hierarchy of values etc. This evaluation is neither necessarily rational nor quantitative. Yet if a mathematical result is to be obtained, both the evaluations and the decisions based on these evaluations need to be quantified. The evaluation (sometimes called “utility”) is quantified by assigning a monetary value to every “variable”. The decision making process is quantified by assuming that each individual acts to maximize utility (the sum of the monetary values of the results of all his choices).
3) What is the system? In actuality, the system is the set of laws that determine the kind of interactions that occur among individuals. In the model, this translates to assumptions that certain factors will remain constant over time.
Once these three aspects are modeled, one ends up with a set of equations that can be solved to determine what utility each individual will be able to achieve. The solution represents an outcome. In certain cases, feasible outcomes may exist that are better for each individual. (This usually happens when there are “externalities” which can be considered mathematically as non-linear effects). The most obvious problem with this argument is that it involves a huge number of variables, so man variables that no human (or computer) can solve the set of equations in any meaningful time. That however, is not my argument. My friend already acknowledges this fact and claims (plausibly) that in certain cases, a social planner may find an approximate solution that is still better than the free market one. My arguement is that: The fact that a (mathematically) feasible better solution exists, does not mean that it is possible to achieve in actuality. The reason is that the sort of actions required to achieve the feasible solution change the system (point 3) that was analyzed. In actual terms, such actions necessarily involve violating the property rights of individuals, thus changing the interactions between people, the monetary values they attach to different choices and the strategies they adopt to maximize their values. In plain language, attempts to achieve the “optimum” solution are lost in a host of unintended consequences. The information that says a better solution is feasible exists not with any single individual but with a vast number of individuals. To put that information to use, even if a social planner is able to approximate it, he needs to communicate it to all the people who will need to act on it. But force (and social planning is all about force) is a very destructive way of communicating. Successful communication is done with persuation and persuation is what the free market is all about.
Now consider a much simpler moral argument. Every value that man achieves is a result of using his mind. And the essential requirement for the mind to work is freedom. When man is free to act as his mind instructs him to do and is responsible for the consequences of his actions, his mind works the best. When he is forced to act against the judgement of his mind, his mind becomes passive and he loses the motivation to use his mind (something that never figures in a mathematical model). In the most fundamental sense of the word good, force can never be good for man.
In his response, following my post on propaganda, my friend clarified that what he meant by propaganda was a one-sided presentation of an idea that does not consider all sides of an issue. The moral idea (in the paragraph above) when supplemented with the practical arguments and all the evidence of the past century becomes a fundamental political principle. And there is no other side to the issue left. As I wrote in this post, as long as one is unsure of something and has not integrated ideas into principles, it is good to be circumspect and consider all pros/cons of all sides of an issue. But on issues on which it is possible to have relevant principles, there is only one side. Fundamental principles do not allow any evaluation in shades of gray. Whether I should be free to act on my own judgement or whether I should allow a social planner to force his whims on me or whether I should become a social planner myself is not an issue where I will weigh the pros/cons of the alternatives.
Finally for the sake of completeness, consider the Pigouvian tax/subsidy to correct for externalities. The first point to be noted is that most externalities go away when property rights are properly defined and implemented. And in fact a tax on pollution is actually quite close to what a property-rights solution to the “problem” of pollution would be. As for the subsidy on education, one can just look at the state of subsidised public education in the U.S. to see how it works. Externalities cause problems in model-based economics because they are non linear effects and most models are linear (eg, price = marginal utility) (for the simple reason that non-linear models are untractable). Man’s mind is not a linear device however, and a linear model does it no justice. Just think of the salesman who negotiates a price (= marginal utility?) or the investor who depends on a virtuous cycle where increase in supply creates a non-existant demand to recover his investment.