So far I have discussed, and tried to defend, two of the assumptions that go into economics: comparability, the assumption that the different things we value are comparable, and non-satiation, the assumption that in any plausible society, present or future, we cannot all have everything we want and must give up some things we desire in order to have others. In talking about value, I have also implicitly introduced an important definition--that value (of things) means how much we value them and that how much we value them is properly estimated not by our words but by our actions. In discussing the trade-off between the value of life and the value of the pleasure of smoking, my evidence that the two are comparable was that people choose to smoke, even though they believe doing so lowers their life expectancy. This definition is called the principle of revealed preference--meaning that your preferences are revealed by your actions.
The first part of the definition of value embodied in the principle of revealed preference might be questioned by those who prefer to base value on some external criterion--what we should want or what is good for us. The second might be questioned by those who believe that their values are not fairly reflected in their actions, that they value health and life but just cannot resist one more cigarette. But economics is supposed to describe how people act, and we are therefore concerned with value as it relates to action. A smoker's statement that he puts infinite value on his own life may help to explain what he believes, but it is less useful for understanding what he will do than is the kind of value expressed when he takes a cigarette out and lights it.
Even if revealed preference is a useful concept for our purpose, should we call what it reveals value? Does not the word carry with it an implication of something beyond mere individual preference? That is a philosophical question that goes beyond the subject of this book. If using the word value to refer equally to a crust of bread in the hands of a starving man and a syringe of heroin in the hands of an addict makes you uncomfortable, then substitute economic value instead. But remember that the addition of "economic" does not mean "having monetary value," "being material," "capable of producing profit for someone," or anything similar. Economic value is simply value to individuals as judged by them and revealed in their actions.
Economics Joke #l: Two economists walked past a Porsche showroom. One of them pointed at a shiny car in the window and said, "I want that." "Obviously not," the other replied.
Choice or Necessity?
The difference between the approaches to human behavior taken by economists and by noneconomists comes in part from the economist's assumptions of comparability and insatiability, in part from the definition of value in terms of revealed preference, and in part from the fundamental assumption of rationality that I made and defended in the previous chapter. One form in which the difference often appears is the economist's insistence that virtually all human behavior should be described in terms of choices. To many noneconomists, this seems deceptive. What, after all, is the point of saying that you choose not to buy something you cannot afford?
When you say that you cannot afford something, you usually mean only that there are other things you would rather spend the money on. Most of us would say that we could not afford a $1,000 shirt. Yet most of us could save up $1,000 in a year if it were sufficiently important--important enough that you were willing to spend only a dollar a day on food (roughly the cost of the least expensive full-nutrition diet--powdered milk, soy beans, and the like), share a one-room apartment with two roommates, and buy your clothing from Goodwill.
Consider an even more extreme case, in which you have assets of only a few hundred dollars and there is something enormously valuable to you that costs $100,000 and will only be available for the next month. In a month, you surely cannot earn that much money. It seems reasonable, in this case at least, to say that you cannot afford it. Yet even here, there is a legitimate sense in which what you really mean is that you do not want it.
Suppose the object were so valuable that getting it made your life wonderful forever after and failing to get it meant instant death. If you could not earn, borrow, or steal $100,000, the sensible thing to do would be to get as much money as possible, go to Reno or Las Vegas, work out a series of bets that would maximize your chance of converting what you had into exactly $100,000, and make them. If you are not prepared to do that, then the reason you do not buy the object is not that you cannot afford its $100,000 price. It is that you do not want it--enough.
In part, the claim that people do not really have any choice confuses the lack of alternatives with the lack of attractive or desirable ones. Having chosen the best alternative, you may say that you had little choice; in a sense you are correct. There may be only one best alternative.
One example of this confusion that I find particularly disturbing is the argument that the poor should be "given" essential services by government even if (as is often the case) they end up having to pay for the services themselves through increased taxes. Poor people, it is said, do not really choose not to go to doctors--they simply cannot afford to. Therefore a benevolent government should take money from the poor and use it to provide the medical services they need.
If this argument seems convincing, try translating it into the language of choice. Poor people choose not to go to doctors because to do so they would have to give up things still more important to them--food, perhaps, or heat. It may sound heartless to say that someone chooses not to go to a doctor when he can do so only at the cost of starving to death, but putting it that way at least reminds us that if you "help" him by forcing him to spend his money on doctors, you are compelling him to make a choice--starvation--that he rejected because it was even worse than the alternative--no medical care--that he chose.
The question of how much choice individuals really have reappears on a larger scale in discussions of how flexible the economy as a whole is--to what extent it can vary the amount of the different resources it uses. Our tendency is to look at the way things are now being done and assume that that way is the only possible one. But the way things are now done is the solution to a particular problem--producing goods as cheaply as possible given the present cost of various inputs. If some input--unskilled labor, say, or energy or some raw material--were much more or less expensive, the optimal way of producing would change.
A familiar example is the consumption of gasoline. If you suggest to someone that if gasoline were more expensive he would use less of it, his initial response is that using less gasoline would mean giving up the job he commutes to or walking two miles each way to do his shopping. Indeed, when oil prices shot up in the early 1970's, many people argued that Americans would continue to use as much gasoline as before at virtually any price, unless the government forced them to do otherwise.
There are many ways to save gasoline. Car pooling and driving more slowly are obvious ones. Buying lighter cars is less obvious. Workers choosing to live closer to their jobs or employers choosing to locate factories nearer to their workers are still less obvious. Petroleum is used to produce both gasoline and heating oil; the refiners can, to a considerable degree, control how much of each is produced. One way of "saving" gasoline is to use less heating oil and make a larger fraction of the petroleum into gasoline instead. Insulation, smaller houses, and moving south are all ways of saving gasoline.
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