The forces of competition and the tendency to profit-maximization operate to mitigate these differences. However, the basic fact of a personnel inves… - Kenneth Arrow

The competitive system can be viewed as an information and decision structure. Initially, each agent in the economy has a very limited perspective. The household knows only its initial holdings of goods (including labor power) and the satisfactions it could derive from different combinations of goods acquired and consumed. The firm knows only the technological alternatives for transforming inputs into outputs. The “communication” takes the form of prices. If the correct (equilibrium) prices are announced, then the individual agents can determine their purchases and sales so as to maximize profits or satisfactions. The prices are then, according to the pure theory, the only communication that needs to be made in addition to the information held initially by the agents. This makes the market system appear to be very efficient indeed; not only does it achieve as good an allocation as an omniscient planner could, but it clearly minimizes the amount of communication needed.

The meaning of information is precisely a reduction in uncertainty. From the viewpoint of economics or decision theory, uncertainty is relevant because it concerns the consequences of decisions. An individual making a decision may be supposed to be choosing one among a set of feasible alternatives. In general, these alternatives are themselves plans extending in time, and he will want to choose the one that yields the most satisfying consequences. These may be profits in successive periods for a business firm, or they may be other satisfactions, such as consumption, power, bequests, or interesting challenges. It can be assumed that the individual compares the entire set of consequences deriving from each alternative in his decision set with those of the others and chooses the preferred one.

Uncertainty means that we do not have a complete description of the world which we fully believe to be true.