Studying oneself is not the most comfortable of enterprises. One is caught between the desire to show oneself in the best possible light and the fear… - Kenneth Arrow

According to this point of view, knowledge is, so to speak, a by-product of production or of investment. In research, on the contrary, it can be said that knowledge is the primary product. The distinction between products and by-products is not important for ordinary goods, because in a competitive regime the marginal costs of the two must be equal. But since knowledge does not have the normal properties of an economic good, it is necessary to study each mode of its production.

I have argued that forecasts will be based on more information than is contained in econometric models and in general on information differing from agent to agent. I also want to argue that they will not necessarily use all the information contained in an econometric model. In fact, the two propositions are intimately linked though they seem to move in opposite directions. We have to assume that information-processing ability is scarce. As I have already said, this is one of the main justifications for and explanations of a decentralized economy. But then it follows that an individual concentrates on acquiring the information most useful to him and will have to crowd out the information which is less useful. In particular, information that is broadly pertinent to the economy as a whole may have very little predictive power for the future of an individual.

In addition to ignoring game aspects of the problem of social choice, we will also assume in the present study that individual values are taken as data and are not capable of being altered by the nature of the decision process itself. This, of course, is the standard view in economic theory (though the unreality of this assumption has been asserted by such writers as Veblen, Professor J. M. Clark, and Knight) and also in the classical liberal creed. If individual values can themselves be affected by the method of social choice, it becomes much more difficult to learn what is meant by one method’s being preferable to another.