Kenneth Arrow Quotes

If the total number of alternatives is two, the method of majority decision is a social welfare function which satisfies Conditions 2–5 and yields a social ordering of the two alternatives for every set of individual orderings.

We don't have much time left. We are moving towards temperature increases of around two degrees Celsius, which is going to have consequences in the tropics, and we will lose things like glaciers. That's not a theory; it's happening right now. It's not a prediction; it's happening right now. But you just sightsee near those glaciers. But the glaciers are a big source of water. And on the questions of water, in California we store our water in a snowpack. When that's gone, the rain will be the same but it won't accumulate. With warming temperatures the snowpack will not work. It might be possible to substitute with dams, but that's complicated. This is conjoined with a big energy problem and I think that we really have to encourage development in this area. Just waiting for technological improvement won't work. We need to encourage it.

The creation of knowledge that constitutes an innovation is in turn dependent on the acquisition and application of existing knowledge; information is an input into the production of information. This background knowledge and the ability to use it are the most important elements of the social context of individually motivated innovation.

The members of an economy—the firms, the consumers, the investors, and the government—make choices. To give a common name to them all, I will refer to them as agents, for indeed their most salient characteristic is that they act. That they make choices implies that they have alternatives, that what was chosen was not inevitable but was in fact only one in a range of opportunities. The opportunities available to a consumer are determined by the income he has and the prices he has to pay for commodities of different use-values.

The conflict of incentives and information is increasingly leading to a diffusion of responsibility for medical decisions. The simple picture of the physician making decisions for the patient has certainly become more complicated. Patients always had a role in choosing to seek medical advice and from whom. Their choices are becoming increasingly restricted as medical practice becomes more organized. The problems of cost control in an insured world are partly met by the increasing use of control of medical services through review by health maintenance organizations and insurance carriers.

There are many unknowns in the creation and use of knowledge as a factor of production. Still, two main lessons stand out:
* Every country or firm must have education and training in technology and science, even if the research is not on par with that being conducted elsewhere. Knowledge cannot be absorbed unless some knowledge is already possessed.
* Countries and firms must be open to new ideas, have multiple sources of new ideas, and see that ideas are diffused. This point strongly argues for freedom of entry, even when it seems to forgo economies of scale.

I want to stress that rationality is not a property of the individual alone, although it is usually presented that way. Rather, it gathers not only its force but also its very meaning from the social context in which it is embedded.

My own interest first centered on the relations between Pareto efficiency and competitive equilibrium. In particular, there was considerable discussion among economists in the late 1940’s about the inefficiencies resulting from rent control and different proposals for arriving at the efficiency benefits of a free market by one or another transition route. Part of the informal efficiency arguments hinged on the idea that under rent control people were buying the wrong kind of housing, say, excessively large apartments. It struck me that an individual bought only one kind of housing, not several. The individual optima were at corners, and therefore one could not equate marginal rates of substitution by going over to a free market. Yet diagrammatic analysis of simple cases suggested to me that the traditional identification of competitive equilibrium and Pareto efficiency was correct but could not be proved by the local techniques of the differential calculus.

My own view is that both endogenous and exogenous elements are important in explaining innovation. Incentives certainly play a role, but so does the general state of scientific knowledge, which is not directly produced by profit-making entities.

As is by now well known, attempts to form social judgments by aggregating individual expressed preferences always lead to the possibility of paradox.

From the point of view of seeking a consensus of the moral imperative of individuals, such consensus being assumed to exist, the problem of choosing an electoral or other choice mechanism, or, more broadly, of choosing a social structure, assumes an entirely different form from that discussed in the greater part of this study.

In view of the magnitude of an economic system, it would take only a very small percentage of improvement in economic stability or growth to make almost any conceivable data collection worthwhile. The situation is analogous to reported results of the use of linear programming in industry; the gains are small in proportion to previous profit levels but still very much larger than the costs of the programming. No country is adequate in respect to its data. In particular the underdeveloped countries, with their ambitious programs, might well ponder whether or not the marginal productivity of investment in better economic statistics is perhaps not higher than almost any conceivable alternative; they have more need and fewer data.

Strictly speaking, decision theory really is concerned only with the fourth part of the division given above, that is, the determination of the computational methods for optimization. Given the determination of the other three factors―the objective function, the range of policy alternatives, and the model―the ideal picture is that someone, presumable the firm that hires the operations researcher, hands him, on a silver platter, an objective function. By talking to the engineers, or by looking into a few scientific laws, he determines the policy alternatives available and also the model.

The domain of the theory of social choice is not in principle the same as that of a theory of justice. In some directions, it is clearly wider, since it is supposed to cover all decision that must be made collectively. On the other hand, it is possible to hold that propositions about distributive justice are not necessarily propositions about collective decisions.

In a capitalist democracy there are essentially two methods by which social choices can be made: voting, typically used to make ‘political’ decisions, and the market mechanism, typically used to make ‘economic’ decisions. In the emerging democracies with mixed economic systems Great Britain, France, and Scandinavia, the same two modes of making social choices prevail, though more scope is given to the method of voting and to decisions based directly or indirectly on it and less to the rule of the price mechanism. Elsewhere in the world, and even in smaller social units within the democracies, the social decisions are sometimes made by single individuals or small groups and sometimes (more and more rarely in this modern world) by a widely encompassing set of traditional rules for making the social choice in any given situation, for example, a religious code.