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Rationality in Economics: Constructivist and Ecological Forms

The principal findings of experimental economics are that impersonal exchange in markets converges in repeated interaction to the equilibrium states implied by…

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Friedrich von Hayek

On Two Forms of Rationality - Rationality in Economics: Constructivist and Ecological Forms by Vernon Smith

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Introduction

The organizing principle throughout this work is the simultaneous existence of the two rational orders: constructivist and ecological. These two orders interact daily in ordinary human interaction,

Note:DUE ORDINI RAZINALI

Roughly, we associate constructivism with attempts to model, formally or informally, rational individual action and to invent or design social systems, and link ecological rationality with adaptive human decision and with group processes of discovery in natural social systems.

Note:MODELLO E ADATTAMENTO

Ecological rationality, however, always has an empirical, evolutionary, and/or historical basis; constructivist rationality need have little, and where its specific abstract propositions lead to some form of implementation, it must survive tests of acceptability, fitness, and/or modification.

Note:EMPIRISMO E RAZIONALISMO

I would conjecture that a critical element in understanding this proposition is to be found in human self-perception. We naturally recognize only one rational order because it is so firmly a part of the humanness of our reason and our mind’s anthropocentric need to think it is in control.

Note:PERCHÈ LA RAZIONALITÀ ECOLOGOCA NON È ACCETTATA? IL BISOGNO DI CREDERSI DOMINANTI

Constructivist Rationality

stems particularly from René Descartes (also Sir Francis Bacon and Thomas Hobbes), who believed and argued that all worthwhile social institutions were and should be created by conscious deductive processes of human reason… In the nineteenth century, Jeremy Bentham and John Stuart Mill were among the leading constructivists….

Note:I PADRI DEL COSTRUTTIVISMO

Mill introduced the much-abused constructivist concept (but not the name) of “natural monopoly.” To Mill it was transparently wasteful and duplicative to have two or more mail carriers operating on the same route.

Note:ESEMPIO: IL CONCETTO DI MONOPOLIO NATURALE

Mill also could not imagine that it would be efficient for two cities to be connected by two parallel railroad tracks (Mill, 1848/1900, Vol. 1, pp. 131, 141–2, Vol. 2, p. 463).

Note:LO SPRECO DELLE STRADE PARALLELE

Many economists are either baffled that equilibrium theory works in these private information environments, or continue to think, speak, and write as if nothing had changed, that equilibrium theory requires complete or perfect information; others avoid confronting the question of what assumptions underlie the operational content of equilibrium theory.

Note:RATIO ECOLOGICA: UNA RIVOLUZIONE NELLA TEORIA GENERALE DELL' EQUILIBRIO

In economic analysis, the resulting exercises are believed to sharpen economic thinking, as “if-then” parables. Yet, these assumptions about the economic environment are unlikely to approximate the level of ignorance that has conditioned either individual behavior or our evolved institutions as abstract norms or rules independent of particular parameters that have survived as part of the world of experience.

Note:COME MODIFICARE IL MODELLO ORIGINALE

The temptation is to ignore this reality because it is poorly understood and does not yield to our familiar but grossly inadequate static modeling tools, and to proceed in the implicit belief that our parables capture what is most essential about what we observe.

Note:PERCHÈ SI FA FINTA DI NIENTE

Limitations and Distractions of Constructivist Rationality

it is necessary to remind ourselves constantly that human activity is diffused and dominated by unconscious, autonomic, neuropsychological systems that enable people to function effectively without always calling upon the brain’s scarcest resource: attention and self-aware reasoning circuitry.

Note:QUEL CHE TRASCURA IL COSTRUTTIVISMO

This is an important economizing property of how the brain works. If it were otherwise, no one could get through the day under the burden of the self-conscious monitoring and planning of every trivial action in detail.

Note:FARE TUTTO SOLO COL CERVELLO È TROPPO ONEROSO

“If we stopped doing everything for which we do not know the reason, or for which we cannot provide a justification . . . we would probably soon be dead” (Hayek, 1988, p. 68).

Note:HAYEK

Imagine the strain on the brain’s resources if at the supermarket a shopper were required to evaluate his or her preferences explicitly for every combination of the tens of thousands of grocery items that are feasible for a given budget.

Note:LA PROVA DEL SUPERMERCATO

The genes but also the cultural characteristics and institutions that survive are the ones that have created biological or cultural descendants who become “ancestors” who live and transmit this information (see Pinker, 1994, 2002).

Note:I SOPRAVVISSUTI

We fail utterly to possess natural mechanisms for reminding ourselves of the brain’s offline activities and accomplishments. This important proposition has led Gazzaniga (1998) to ask why the brain fools the mind into believing it is in control: By the time we think we know something – it is part of our conscious experience – the brain has already done its work.

Note:CREDERE DI SAPERE

And to Hayek, who had a thorough grasp of these propositions, but without the advantage afforded by recent neuroscience understanding, what was the “fatal conceit”? “The idea that the ability to acquire skills stems from reason.”

Note:L'ERRORE FATALE

That the brain is capable of off-line subconscious learning is shown by experiments with amnesiacs who are taught a new task. They learn to perform well, but memory of having learned the task escapes them (Knowlton et al., 1996).

Note:MIRACOLI DELL'AMNESIA

Also, there are numerous anecdotal reports of people seeking a solution to a problem who abandon it unsolved, but awaken in the morning with a solution… For example, Dmitri Mendeleyev reported that the critical rule underlying his periodic table of the elements came in a dream after unsuccessful efforts to gain insight while awake. Poincaré (1913) reports having given up on solving a particularly difficult mathematical problem only to have the solution suddenly appear to him on a trip to Lyon….

Note:SVEGLIARSI E RISOLVERE PROBLEMI

the other side of the phenomenon of subconscious problem solving is the brain’s ability to shut out all sense of self-awareness in the process of carrying out a difficult task

Note:QUANDO IL CERVELLO ORDINA ALLA MENTE

The current view is that, “Memories develop in several stages. After the initial encoding of new information during learning, memories are consolidated ‘off-line,’ seemingly while not being actively thought about through a cascade of events that is not well understood. In humans and other mammals, such an enhancement of recent memory may occur during sleep”… In a new study of navigation learning in rats, Foster and Wilson (2006) show evidence of memory consolidation during rest periods while awake….

Note:MEMORIA CONSOLIDATA OFF LINE

people are not aware of a great range of socioeconomic phenomena, such as the productivity of social exchange systems and the external order of markets that underlie the creation of social and economic wealth.

Note:INCONSCIO ED ECONOMIA

Ecological Rationality

an ecological system, designed by no one mind, that emerges out of cultural and biological evolutionary processes… Paraphrasing Gigerenzer et al. (“A heuristic is ecologically rational to the degree that it is adapted to the structure of an environment” [1999, p. 13]),

Note:ORDINE CHE EMERGE DALLA SELEZIONE

there are limitations to what we can deliberately bring about, and . . . that that orderliness of society which greatly increased the effectiveness of individual action was . . . largely due to a process . . . in which practices . . . were preserved because they enabled the group in which they had arisen to prevail over others” (pp. 8–9).

Note:VINCERE SENZA SAPERE PERCHÈ

People follow rules – morality, to David Hume – without being able to articulate them, but they may nevertheless be discoverable.

Note:LA RAGIONE RAZIONALIZZA... AL MASSIMO

This is the intellectual heritage of the Scottish philosophers and Hayek, who described and interpreted the social and economic order they observed and its ability to achieve desirable outcomes.

Note:ILLUMINISMO SCOZZESE

Hume, an eighteenth-century precursor of Herbert Simon, was concerned with the limits of reason and the bounds on human understanding, and with scaling back the exaggerated claims and pretensions of Cartesian constructivism.

Note:HUME VS CARTESIO

To Hume, rationality was phenomena that reason discovers in human institutions and practices. Thus, “the rules of morality . . . are not conclusions of our reason” (Hume, 1739/1985, p. 509). Smith developed the idea of emergent order for economics. Truth is discovered in the form of the intelligence embodied in rules

Note:LA RAGIONE OPERA A RITROSO

To paraphrase Smith, people in these experiments are led to promote group welfare, enhancing social ends that are not part of their intention. This principle is supported by hundreds of experiments whose environments and institutions (sealed bid, posted offer, and others besides CDA) may exceed the capacity of formal game-theoretic analysis to articulate predictive models.

Note:L'ECONOMIA SPERIMENTALE CONFERMA GLI SCOZZESI

What experimentalists have (quite unintentionally) brought to the table is a methodology for objectively testing the Scottish-Hayekian hypotheses under stronger controls than are otherwise available. This answers the question that Milton Friedman is said to have raised concerning the validity of Hayek’s theory/reasoning: “How would you know?”

Note:TESTARE L'IPOTESI HAYEK

Economic historian Douglass North (1990) and political economist Elinor Ostrom (1982, 1990) have long explored the intelligence and efficacy embodied in emergent socioeconomic institutions that solve, or fail to solve, problems of growth and resource management.

Note:OSTROM E NORTH

The distinction between ecological and constructivist rationality is in principle related to Simon’s distinction between subjective and objective rationality, procedural and substantive rationality, and between people making “good-enough” satisfactory decisions and making optimal decisions (Simon, 1955, 1956).

Note:HERBERT SIMON

procedural rationality and “satisficing” moves of subjects can converge over time to the substantively rational competitive outcome of equilibrium theory. (For a formal example, see Lucas, 1986.)

Note:LA CONVERGENZA DELLE RAZIONALITÀ

understanding decision making requires knowledge beyond the traditional bounds of economics,12 a challenge to which Hume and Smith were not strangers. Thus, “an economist who is only an economist cannot be a good economist” (Hayek, 1956).

Note:OLTRE L'ECONOMIA

Hume and Smith were part of a broader “Scottish enlightenment” centered in Edinburgh that blossomed in the period from 1745 to 1789. It embraced philosophy, political and social systems, economics, psychology and the mind, science, and poetry and literature (Robert Burns and others).

Note:ANCORA SULL'ILLUMINISMO SCOZZESE

China’s Great Leap Forward was a constructivist plan, blind to the accumulated intelligence and efficacy of ancient Chinese cultural traditions,

UN ESEMPIO DI COSTRUTTIVISMO

Stuffing Envelopes By Steven Landsurg

Stuffing Envelopes By Steven Landsurg

• This is a story about some economists who set out to study altruism and ended up discovering something very frightening about human nature.
• Adam Smith. who needs altruism when we've got greed?... greed can be far more efficient than altruism. An altruistic butcher can't serve his neighbors well unless he knows how many want beef on the table and how many want chicken.
• Edempio. If you happen to like this article so much that you decide to buy a lifetime subscription to REASON, some Asian farmer has to grow another linseed plant. That's because the ink in this magazine is made from linseed oil. How does the Asian farmer know you need more linseed? Because rising subscription numbers set off a chain reaction: They raise the demand for ink, which raises the price of ink, which raises the demand for linseed, which raises the price of linseed.
• economists spend a lot of time theorizing about both the prevalence and the consequences of altruism. Enter Vernon Smith.
• Here's one of Smith's experiments: Two total strangers are placed in separate rooms. They never meet, they never learn each others' names, and they come and go by separate entrances. One of them is selected randomly to receive 10 one-dollar bills and an envelope. He can put any number of bills in the envelope and send it by messenger to the other subject. Then everyone takes his money and goes home. Simple economics predicts that no money ever goes in the envelope. 1/3 dà.
• Not even Mother Teresa was in the habit of sending money to total strangers about whom she knew nothing.
• Why, then, does any money ever get passed to the other room? My guess is that it has nothing to do with altruism or charity and everything to do with the subjects' suspicion that they're being observed
• La seconda inquietante versione dell'esperimento. subjects know that everything they put in the envelope will get tripled by the experimenter before it's sent to the other room... virtually all of the subjects put at least a dollar in the envelope... In other words, subjects give more generously when they can get a bigger bang for their buck.
• La scoperta: they're paying for the privilege of taking money away from one total stranger -- namely the taxpayer
• Da notare: the subjects do all this without knowing anything at all about either stranger or having any reason to believe that one is more deserving than the other... It's not like they're taking from the rich to give to the poor; they're just randomly taking from some people so they can give to others.
• they just plain enjoy the capricious exercise of power, bestowing good fortune on some and bad fortune on others
• Conclusione. the reason we have a redistributive tax system is not because people want to help the poor or the unfortunate or the incapacitated; it's because people enjoy moving other people's money around just to make mischief.
• Tentativo di assolvere: They're just not conscious of the fact that the money they transfer has to come from somewhere."
• Replica: These subjects are mostly university students, and they don't realize that when you give away money, it has to come from somewhere? And we allow these people to vote?

continua

Tre moltitudini

Molti affermano che "il mercato ha bisogno di regole".

Molti non sanno dissimulare la loro diffidenza verso il mercato.

Molti non capiscono nemmeno cosa sia il mercato.

Ecco, queste tre moltitudini tendono a coincidere.

Vernon Smith è forse la persona più idonea per illustrare questa coincidenza, è forse la persona più idonea ad illustrare la razionalità intrinseca dell' economia.

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A volte ci si scorda che le "regole" tanto invocate dovrebbero giungere dalla politica.

Ma tutti noi ammettiamo che l' unica "politica" sana sia quella di matrice democratica.

Spingendo oltre la riflessione si deve ammettere che questa preferenza deriva dal fatto che i regimi democratici prevedono una competizione.

Solo la presenza di un elemento competitivo "salva" la Politica.

Ecco, ma se le cose stanno così, è proprio accentuando questo elemento che la politica migliora.

Ma accentuare questo elemento trasforma lentamente la Politica in Economia. Il mercato è infatti il luogo deputato per la competizione.

In ultima analisi è dunque il "mercato" che deve dare regole al mercato.

Un esempio tanto per capirci: il mercato necessita di regole, la politica le fornisce, la globalizzazione spinge la politica verso alcune regole piuttosto che altre.

Ma cio' che chiamiamo "globalizzazione" non è altro che il mercato internazionale.

Cosa è successo? E' successo che il mercato ha regolato il mercato.

Adesso intravvediamo meglio cosa intende vernon Smith quando dice che "l' economia ha una sua razionalità interna".

E magari capiamo anche meglio la coincidenza delle tre moltitudini.