fevereiro 14, 2015

Franklin -- The Science of Conjecture

[About witch trials] I have my ears battered with a thousand such flim-flams as these: "Three persons saw him such a day in the east; three, the next day in the west; at such a hour, in such a place, in such habit"; in earnest, I should not believe myself. How much more natural and likely do I find it that two men should lie, than that one man in twelve hours' time should fly with the wind from east to west? How much more natural that our understanding should be carried from its place by the volubility of our disordered minds, than that one of us should be carried by a strange spirit upon a broomstick, flesh and bones that we are, up the shaft of a chimney? Let us not seek illusions from without and unknown, we who are perpetually agitated with illusions domestic and our own. Methinks one is pardonable in disbelieving a miracle, at least, at all events where one can allude its verification as such, by means not miraculous; and I am of St. Augustine's opinion, that "tis better to lean towards doubt than assurance, in things hard to prove and dangerous to believe." ... It is true, indeed, that the proofs and reasons that are founded upon experience and fact, I do not go to untie, neither have they any end; I often cut them, as Alexander did the Gordian knot. After all, 'tis setting a man's conjectures at a very high price, upon them to cause a man to be roasted alive. -- Montaigne, Essays 3 chp.11.

The story of the decline of Science in the West and its survival in the East is a familiar one. The twelfth century saw the reappearance in Western Europe of the scientific point of view on the world and the recovery, translation, and assimilation of all the main ancient scientific texts. What the later Middle Ages made of their scientific legacy is, by common consent, less impressive than their achievements in such files as philosophy, theology, and law. The long debate of why the scientific revolution did not take place before it did is not subject to conclusive resolution, but there is a wide support for the view that the Scholastic method, relying too much on conceptual and textual analysis, failed to devote enough attention to experiment and measurement and their relation to theory. Nevertheless, there are areas of science in which purely conceptual work is entirely appropriate, namely the more mathematical sciences, and it is there that medieval science is strongest. Optics and astronomy, in particular, were regarded as actually part of mathematics and were central to both teaching and research. (p.140)

It is in [Nicole] Oresme's mathematical works that we must look for a full treatment of his ideas on probability [...] a passage connects relative frequency ideas with symmetric notions of insufficient reason. He divides the possible into three. "Either it is equally possible, or it is improbable, or it is probable. An example of the first way: The number of stars is even; the number of stars is odd. One is necessary, the other impossible. However, we have doubts as to which is necessary, so that we say of each that it is possible... sometimes in such cases we have no reason for one part; and sometimes we do have a reason, and then it is called a 'problem'... An example of the second way: The number of stars is a cube. Now indeed, we say that it is possible but not, however, probable or credible or likely (probabile aut opinabile aut verisimile), since such numbers are much fewer than others." (pg.141-2)

The frequently repeated tale that the fragments of the True Cross would have added up to a whole forest appears to be a modern myth. Indeed, it is only one of a cluster of widely credited myths about the Middle Ages (in the Middle Ages it was believed the earth is flat; lords enjoyed droit de seigneur over peasant women; the Scholastic debated how many angels could dance on the head of a pin), raising questions about which age is really the more credulous. (p.181)

Since the time of Democritus, one of the chief irritants producing the pearl of philosophy has been the challenge of skepticism, the worry that false sense impressions are sometimes indistinguishable from true ones. The experience of illusions of perception is familiar -- the oar that appears bent in water, the tower that appears round from a distance but square nearby. As Aristotle explains, "Which, then, of these impressions are true and which are false are not obvious, for the one set is no more true than the other, but both are alike." [...] This symmetry argument is the driving force behind skepticism. (p.196)

[About the book On Signs by the Epicurean Philodemus] The work describes the debate between Stoics and Epicureans over, essentially, the problem of induction, or the inference to general facts from observations. To infer "All men are mortal" from "All observed men are mortal" requires, according to the Stoics, following Aristotle, rational insight into the nature of man. The Epicureans maintain that there are no such rational insights into natures and that one can only make the inference from suitable repeated and suitably checked experiences. The debate is in principle the same as the modern one about whether inductive argument needs laws of nature and a uniformity of nature principle, or whether it is a purely statistical procedure like arguing from sample to population. (p.201)

Earlier Scholastic thought made some attempt to grapple with the problem of why a astronomical theory's agreeing with the observations should be a reason for believing it and whether the belief should amount to certainty or not. Kepler tried to find something in common between the Copernican and Ptolemaic theories, which would account for the appearances and thus explain why they made the same predictions, although one was right and one was wrong about the underlying causes. But Descartes is asserting something over and above a simple recommendation of inference to the best explanation. He asserts that there is no need to find the true underlying model to make the correct prediction. It is the first clear statement of the dream of modern statistical inference: to make true predictions independently of difficult inquiry into inner causes. The modern economic modeling that attempts to forecast unemployment, interest rates, and so on without any commitment to grand economic theories is a continuation of Descartes' project. (p.221)

Ockham is now best known for the principle of economy in reasoning known as Ockham's Razor. This is a misnomer for two reasons. First he did not originate it; there is the inevitable origin in Aristotle. The phrase "We consider it a good principle to explain the phenomena by the simplest hypothesis possible" is in Ptolemy. Formulations like "It is vain to do with more what can be done with fewer" and "A plurality is not to be posited without necessity" are Scholastic commonplaces from the early thirteenth century. Second, though he does repeat these ideas frequently, Ockham's contribution is more to restrict the operation of the principle, in the interests of God's absolute power: "God does many things by means of more which He could have done by means of fewer, simply because He wishes it, and no other cause is to be sought. From the very fact that Ge wishes it, it is done suitably, and not in vain." In the Eucharist, especially, Ockham holds that a plurality of miracles is to be postulated, simply because that pleases God. (p.241)

Serious mathematical thought on the subject [dice], however, needs a sufficiently numerical culture. Such a culture became established in fourteenth-century Italy, which was responsible for a number of the crucial steps in creating a tradition of skill in applied numerical calculation. It was the scene of many of the first mechanical public clocks, for example, of the invention of double-entry bookkeeping and, as we saw, of insurance. Especially notable is the discovery of the correct means of predicting the future numerically, tables of compound interest. As experience was gain with numbers, it was realized that calculation was not an intellectual feat reserved for thinkers of genius but (using Arabic numerals with a zero) could be reduced to simple rules and taught to children. These rules - modern-day primary school arithmetics - were taught (in Italy) to merchant's sons in the commercial arithmetic schools of the Italian city-states. The better teachers in these schools went further, developing much of the modern high school mathematics, in particular algebra, in the sense of problem solving using the manipulation of unknown numbers represented by letters. As with modern textbook authors on algebra, the Italian writers had the custom of illustrating their techniques in a number of unrealistic 'real life' examples to which the techniques 'apply'. Simple number problems arising from dice occasionally make an appearance. (p.292ff)

That the vast majority of probabilistic inferences are unconscious is obvious from observing animals, for it is not just the human environment that is uncertain but the animal one in general. To find a mechanism capable of performing probabilistic inference (as distinct from talking about it), one need look no further than the brain of the rat, which generates behavior acutely sensitive to small changes in the probability of the results of that behavior. Naturally so, since the life on animals is a constant balance between coping adequately with risk or dying. [...] Some further light on what the brain does is cast by simple artificial neural nets, whose behavior after training on noisy data can be interpreted as implicit estimates of probabilities. These animals and machines studies confirm in the most direct way that, to behave probabilistically, it is not necessary to have anything like explicit estimates of probabilities or ways of talking about them. (p.324)

The influence of Aristotle on the development of thought, though widely recognized, is underrated. We are all in his orbit. ("Aristotle's works are full of platitudes in much the same way as Shakespeare's Hamlet is full of quotations") Everything is in Aristotle's somewhere - at least in potency but often in actuality. And the reason we underrate his contributions is, of course, precisely that it has become platitudinous: we forget about it, for the same reason that we forget the air we breathe. Anything that has become background, or context, or tradition is no longer salient, sometimes no longer represented symbolically at all. The Meno theory really is true of what we have learn from Aristotle: we have forgotten that we learned it, but it is still there, waiting to surprise us when we are induced to remember it. But there is another reason that we do not notice our Aristotelianism. Aristotle is a philosopher with more respect than most for 'what seems so to all, or to most, or to the wise'. His philosophy has none of the paradoxes repugnant to common sense that render the thought of other 'great philosophers' so memorable. (p.344)

From around 1770, English law adopted the phrase 'proof beyond reasonable doubt' (originally defined as equivalent to 'moral certainty') for the standard of proof required in a criminal case. But the status of the rule caused confusion. Even when the rule was believed to be understood, no number became attached to it. Instead, attempts to explain it have been purely linguistic, as in the 1947 case of Miller v. Minister for Pensions, in which Lord Denning declared that in a criminal charge, "that degree is well settled. It need not reach a certainty, but it must carry a high degree of probability. Proof beyond a reasonable doubt does not mean proof beyond the shadow of a doubt. The law would fail to protect the community if it admitted fanciful possibilities to deflect the course of justice. If the evidence is so strong against a man as to leave only a remote possibility in his favor, which can be dismissed with the sentence, 'of course it is possible but not in the least probable', the case is proved beyond reasonable doubt, but nothing short of that will suffice." (p.366)

dezembro 30, 2014

"setting a man's conjectures at a very high price"

[About witch trials] I have my ears battered with a thousand such flim-flams as these: "Three persons saw him such a day in the east; three, the next day in the west; at such a hour, in such a place, in such habit"; in earnest, I should not believe myself. How much more natural and likely do I find it that two men should lie, than that one man in twelve hours' time should fly with the wind from east to west? How much more natural that our understanding should be carried from its place by the volubility of our disordered minds, than that one of us should be carried by a strange spirit upon a broomstick, flesh and bones that we are, up the shaft of a chimney? Let us not seek illusions from without and unknown, we who are perpetually agitated with illusions domestic and our own. Methinks one is pardonable in disbelieving a miracle, at least, at all events where one can allude its verification as such, by means not miraculous; and I am of St. Augustine's opinion, that "tis better to lean towards doubt than assurance, in things hard to prove and dangerous to believe." ... It is true, indeed, that the proofs and reasons that are founded upon experience and fact, I do not go to untie, neither have they any end; I often cut them, as Alexander did the Gordian knot. After all, 'tis setting a man's conjectures at a very high price, upon them to cause a man to be roasted alive. -- Montaigne, Essays 3 chp.11.

dezembro 21, 2014

Georgescu-Roegen - The Entropy Law & the Economic Process (1973)

[M]y point is not that arithmetization of science is undesirable. 'Whenever arithmetization can be worked out, its merits are above all words of praise. My polnt is that wholesale arithmetization is impossible, that there is valid knowledge even without arithmetization, and that mock arithmetization is dangerous if peddled as genuine. Let us also note that arithmetization alone does not warrant that a theoretical edifice is apt and suitable. As evidenced by chemistry -- a science in which most attributes are quantifiable, hence, arithmomorphic -- novelty by combination constitutes an even greater blow to the creed "no science without theory." (p.15)

The verdict is indisputable: no social science can subserve the art of government as efficaciously as physics does the art of space travel, for example. Nevertheless, some social scientists simply refuse to reconcile themselves to this verdict and, apparently in despair, have come out with a curious proposal: to devise means which will compel people to behave the way "we" want, so that "our" predictions will always come true. The project, in which we recognize the continual striving for a ''rational" society beginning with Plato's, cannot succeed (not even under physical coercion, for a long time) simply because of its blatant petitio principii: the first prerequisite of any plan is that the behavior of the material involved should be completely predictable, at least for some appreciable period. But aggressive scholarship will never run out of new plans for the "betterment of mankind." Since the difficulties of making an old society behave as we want it can no longer be concealed, why not produce a new society according to our own "rational" plans? (p.16)

It is fashionable nowadays to indulge in estimating how large a population our earth can support. Some estimates are as low as five billions, others as high as forty-five billions. However, given the entropic nature of the economic process by which the human species maintains itself, this is not the proper way to look at the problem of population. Perhaps the earth can support even forty-five billion people, but certainly not ad infinitum. We should therefore ask "how long can the earth maintain a population of forty-five billion people?'' And if the answer is, say, one thousand years, we still have to ask "what will happen thereafter?" All this shows that even the concept of optimum population conceived as an ecologically determined coordinate has only an artificial value. [...] Man's natural dowry, as we all know, consists of two essentially distinct elements: (1) the stock of low entropy on or within the globe, and (2) the flow of solar energy, which slowly but steadily diminishes in intensity with the entropic degradation of the sun. But the crucial point for the population problem as well as for any reasonable speculations about the future exosomatic evolution of mankind is the relative importance of these two elements, For, as surprising as it may seem, the entire stock of natural resources is not worth more than a few days of sunlight! [...] In a different way than in the past, man will have to return to the idea that his existence is a free gift of the sun. (p.20ff)

Anatomically, theoretical science is logically ordered knowledge. A mere catalog of facts, as we say nowadays, is no more science than the materials in a lumber yard are a house. Physiologically, it is a continuous secretion of experimental suggestions which are tested and organically integrated into the science's anatomy. In other words, theoretical science continuously creates new facts from old facts, but its growth is organic, not accretionary. Its anabolism is an extremely complex process which at times may even alter the anatomic structure. We call this process "explanation" even when we cry out "science does not explain anything." Teleologically, theoretical science is an organism in search of new knowledge. (p.37)

There can be no doubt that the decumulation of a machine is not a mechanical spreading in time of the machine as is the case with the stock of provisions of an explorer, for instance. When we "decumulate" a machine we do not separate it into pieces and use the pieces one after another as inputs until all parts are consumed. Instead, the machine is used over and over again in a temporal sequence of tasks until it becomes waste and has to be thrown away. A machine is a material stock, to be sure, but not in the sense the word has in "a stock of coal." If we insist on retaining the word, we may say that a machine is a stock of services (uses). But a more discriminating (and hence safer) way of describing a machine is to say that it is a fund of services

The difference between the concept of stock and that of fund should be carefully marked, lest the hard facts of economic life be distorted at everyone's expense. If the count shows that a box contains twenty candies, we can make twenty youngsters happy now or tomorrow, or some today and others tomorrow, and so on. But if an engineer tells us that one hotel room will probably last one thousand days more, we cannot make one thousand roomless tourists happy now. We can only make one happy today, a second tomorrow, and so on, until the room collapses. [...] The use of a fund (i.e., its "decumulation") requires a duration. Moreover, this duration is determined within very narrow limits by the physical structure of the fund. We can vary it only little, if at all. If one wishes to "decumulate" a pair of shoes, there is only one way open to him: to walk until they become waste (of course, one may sell the shoes. But this would mean decumulation of the shoes as a stock not decumulation of the shoes as a fund of services.) In contrast with this, the decumulation of a stock may, conceivably take place in one single instant, if we wish so. And to put the dots on all significant i's, let us also observe that the "accumulation" of a fund too, differs from the accumulation of a stock. A machine does not come into existence by the accumulation of the services it provides as a fund: it is not obtained by storing these services one after another as one stores winter provisions in the cellar. Services cannot be accumulated as the dollars in a saving account or the stamps in a collection can. They can only be used or wasted.

Nothing more need be said to prove that also the use of the term "flow" in connection with the services of a fund is improper if "flow" is defined as a stock spread over time. In fact, the generally used expression "the flow of services" tends to blur -- at times, it has blurred -- the important differences between two mechanisms, that by which the prices of services and that by which the prices of material objects are determined. The inevitable trap of this ambiguous use of "flow" is that, because a flow can be stored up, we find it perfectly normal to reason that services are "embodied" in the product. Only the materials that flow into a production process can be embodied in the product. The services of the tailor's needle, for example, cannot possibly be embodied in the coat -- and if one finds the needle itself embodied there it is certainly a regrettable accident. The fact that in certain circumstances the value of services passes into the value of the product is to be explained otherwise than by simply regarding a machine as a stock of services that are shifted one after another into the product. 

The difference between flow and service is so fundamental that it separates even the dimensionalities of the two concepts. For this reason alone, physicists would not have tolerated the confusion for long. The amount of a flow is expressed in units appropriate to substances (in the broad sense) -- say pounds, quarts, feet, etc. The rate of flow, on the other hand, has a mixed dimensionality, (substance)/(time). The situation is entirely reversed in the case of services. The amount of services has a mixed dimensionality in which time enters as a factor, (substance) x (time). If a plant uses one hundred workers during a working day (eight hours), the total of the services employed is eight hundred man x hour. If by analogy with the rate of flow we would like to determine the ratio of service for the same situation, by simple algebra the answer is that this rate is one hundred men, period. The rate of service is simply the size of the fund that provides the service and consequently is expressed in elemental units in which the time factor does not intervene. (p.226ff)

A leading symptom is that purists maintain that thermodynamics is not a legitimate chapter of physics. Pure science, they say, must abide to the dogma that natural laws are independent of man's own nature, whereas thermodynamics smacks of anthropomorphism. And that it does so smack is beyond question. But the idea that man can think of nature in wholly nonanthropomorphic terms is a patent contradiction in terms. Actually, force, attraction, waves, particles, and, especially, interpreted equations, all are man-made notions. Nevertheless, in the case of thermodynamics the purist viewpoint is not entirely baseless: of all physical concepts only those of thermodynamics have their roots in economic value and, hence, could make absolutely no sense to a nonanthropomorphic intellect.

A nonanthropomorphic mind could not possibly understand the concept of order-entropy which, as we have seen, cannot be divorced from the intuitive grasping of human purposes. For the same reason such a mind could not conceive why we distinguish between free and latent energy, should it see the difference at all. All it could perceive is that energy shifts around without increasing or decreasing. It may object that even we, the humans, cannot distinguish between free and latent energy at the level of a single particle where normally all concepts ought to be initially elucidated.

No doubt, the only reason why thermodynamics initially differentiated between the heat contained in the ocean waters and that inside a ship's furnace is that we can use the latter but not the former. But the kinship between economics and thermodynamics is more intimate than that. Apt though we are to lose sight of the fact, the primary objective of economic activity is the self-preservation of the human species. Self-preservation in turn requires the satisfaction of some basic needs-which are nevertheless subject to evolution. The almost fabulous comfort, let alone the extravagant luxury, attained by many past and present societies has caused us to forget the most elementary fact of economic life, namely, that of all necessaries for life only the purely biological ones are absolutely indispensable for survival. The poor have had no reason to forget it. And since biological life feeds on low entropy, we come across the first important indication of the connection between low entropy and economic value. For I see no reason why one root of economic value existing at the time when mankind was able to satisfy hardly any non biological need should have dried out later on.

Casual observation suffices now to prove that our whole economic life feeds on low entropy, to wit, cloth, lumber, china, copper, etc., all of which are highly ordered structures. But this discovery should not surprise us. It is the natural consequence of the fact that thermodynamics developed from an economic problem and consequently could not avoid defining order so as to distinguish between, say, a piece of electrolytic copper -- which is useful to us -- and the same copper molecules when diffused so as to be of no use to us. We may then take it as a brute fact that low entropy is a necessary condition for a thing to be useful. (p.277ff)

The corresponding symptoms in analytical studies are even more definite. First, there is the general practice of representing the material side of the economic process by a closed system, that is, by a mathematical model in which the continuous inflow of low entropy from the environment is completely ignored. But even this symptom of modern econometrics was preceded by a more common one: the notion that the economic process is wholly circular. Special terms such as roundabout process or circular flow have been coined in order to adapt the economic jargon to this view. One need only thumb through an ordinary textbook to come across the typical diagram by which its author seeks to impress upon the mind of the student the circularity of the economic process.

The mechanistic epistemology, to which analytical economics has clung ever since its birth, is solely responsible for the conception of the economic process as a closed system or circular flow. As I hope to have shown by the argument developed in this essay, no other conception could be further from a correct interpretation of facts. Even if only the physical facet of the economic process is taken into consideration, this process is not circular, but unidirectional. As far as this facet alone is concerned, the economic process consists of a continuous transformation of low entropy into high entropy, that is, into irrevocable waste or, with a topical term, into pollution. The identity of this formula with that proposed by Schrödinger for the biological process of a living cell or organism vindicates those economists who, like Marshall, have been fond of biological analogies and have even contended that economics "is a branch of biology broadly interpreted.". The conclusion is that, from the purely physical viewpoint, the economic process is entropic: it neither creates nor consumes matter or energy, but only transforms low into high entropy. (p.281)

Low entropy is a necessary condition for a thing to have value. This condition, however, is not also sufficient. The relation between economic value and low entropy is of the same type as that between price and economic value. Although nothing could have a price without having an economic value, things may have an economic value and yet no price. For the parallelism, it suffices to mention the case of poisonous mushrooms which, although they contain low entropy, have no economic value. (p.282)

we cannot mine the stock of solar energy at a rate to suit our desires of the moment. We can use only that part of the sun's energy that reaches the globe at the rate determined by its position in the solar system. With the stocks of low entropy in the earth's crust we may be impatient and, as a result, we may be impatient-as indeed we are with their transformation into commodities that satisfy some of the most extravagant human wants. But not so with the stock of sun's energy. Agriculture teaches, nay, obliges man to be patient-a reason why peasants have a philosophical attitude in life pronouncedly different from that of industrial communities. (p.297)

In a broad perspective we may say that mankind disposes of two sources of wealth: first, the finite stock of mineral resources in the earth's crust which within certain limits we can decumulate into a flow almost at will, and second, a flow of solar radiation the rate of which is not subject to our control. In terms of low entropy, the stock of mineral resources is only a very small fraction of the solar energy received by the globe within a single year. More precisely, the highest estimate of terrestrial energy resources does not exceed the amount of free energy received from the sun during four days! [...] because the low entropy received from the sun cannot be converted into matter in bulk, it is not the sun's finite stock of energy that sets a limit to how long the human species may survive. Instead, it is the meager stock of the earth's resources that constitutes the crucial scarcity. Let S be this stock and r the average rate at which it may be decumulated. Clearly, S = r x t, where t stands for the corresponding duration of the human species. This elementary formula shows that the quicker we decide to decumulate S, the shorter is t. Now, r may increase for two reasons. First, the population may increase. Second, for the same size of population we may speed up the decumulation of the natural resources for satisfying man-made wants, usually extravagant wants.

The conclusion is straightforward. If we stampede over details, we can say that every baby born now means one human life less in the future. But also every Cadillac produced at any time means fewer lives in the future. Up to this day, the price of technological progress has meant a shift from the more abundant source of low entropy-the solar radiation to the less abundant one--the earth's mineral resources. True, without this progress some of these resources would not have come to have any economic value. But this point does not make the balance outlined here less pertinent. Population pressure and technological progress bring ceteris paribus the career of the human species nearer to its end only because both factors cause a speedier decumulation of its dowry. The sun will continue to shine on the earth, perhaps, almost as bright as today even after the extinction of mankind and will feed with low entropy other species, those with no ambition whatsoever. For we must not doubt that, man's nature being what it is, the destiny of the human species is to choose a truly great but brief, not a long and dull, career.

"Civilization is the economy of power [low entropy]," as Justus von Liebig said long ago, but the word economy must be understood as applying rather to the problems of the moment, not to the entire life span of mankind. Confronted, in the distant future, with the impending exhaustion of mineral resources (which caused Jevons to become alarmed about the coal reserves), mankind -- one might try to reassure us -- will retrace its steps. The thought ignores that, evolution being irrevocable, steps cannot be retraced in history. (p.303ff)

[T]he usual denunciation of standard economics on the sole ground that it treats of "imaginary individuals coming to imaginary markets with ready-made scales of bid and offer prices" is patently inept. Abstraction, even if it ignores Change, is "no exclusive privilegium odiosum" of the economic science, for abstraction is the most valuable ladder of any science. In social sciences, as Marx forcefully argued, it is all the more indispensable since there "the force of abstraction" must compensate for the impossibility of using microscopes or chemical reactions. However, the task of science is not to climb up the easiest ladder and remain there forever distilling and redistilling the same pure stuff. Standard economics, by opposing any suggestion that the economic process may consist of something more than a jigsaw puzzle with all its elements given, has identified itself with dogmatism. And this is a privilegium odiosum that has dwarfed the understanding of the economic process wherever it has been exercised. (p.319)

The question is why a science interested in economic means, ends, and distribution should dogmatically refuse to study also the process by which new economic means, new economic ends, and new economic relations are created. (p.320)

[T]he immense satisfaction which Understanding derives from arithmomorphic models should not mislead us into believing that their other roles too are the same in both social and natural sciences. In physics a model is also "a calculating device, from which we may compute the answer to any question regarding the physical behavior of the corresponding physical system." [Bridgman, The Nature of Physical Theory] The same is true for the models of engineering economics. The specific role of a physical model is better described by remarking that such a model represents an accurate blueprint of a particular sector of physical reality. But [...] an economic model is not an accurate blueprint but an analytical simile. Economists are fond of arguing that since no model, whether in physics or economics, is accurate in an absolute sense we can only choose between a more and a less accurate model. Some point out also that after all how accurate we need to be depends on our immediate purpose: at times the less accurate model may be the more rational one to use. All this is perfectly true, but it does not support the further contention -- explicitly stated by Pareto -- that it is irrelevant to point out the inaccuracy of economic models. Such a position ignores an important detail, namely, that in physics a model must be accurate in relation to the sharpest measuring instrument existing at the time. If it is not, the model is discarded. Hence, there is an objective sense in which we can say that a physical model is accurate, and this is the sense in which the word is used in" accurate blueprint." In social sciences, however, there is no such objective standard of accuracy. Consequently, there is no acid test for the validity of an economic model. And it is of no avail to echo Aristotle, who taught that a model is "adequate if it achieves that degree of accuracy which belongs to its subject matter." One may always proclaim that his model has the proper degree of accuracy. Besides, the factors responsible for the absence of an objective standard of accuracy also render the comparison of accuracy a thorny problem. (pg.332ff)

From the deterministic viewpoint, the notion of "rational behavior" is completely idle. Given his tastes, his inclinations, and his temperament, the person who smokes in spite of the warning that "smoking may be hazardous to your health" acts from a definite ground and, hence, cannot be taxed as irrational. And if we accept the conclusions biologists have derived from the study of identical twins, that every man's behavior is largely determined by his genotype, then criminals and warmongers are just as "rational" as the loving and peaceful people. But for a determinist even nurture (whether ecological, biotic, or cultural) cannot be otherwise than what it is: together with nature, nurture holds the individual in a predetermined and unrelenting grip. This is probably why, when a social scientist speaks of irrational behavior, he generally refers to a normative criterion. Take the villagers in some parts of the world who for the annual festival kill practically all the pigs in the village. They are irrational-we say-not only because they kill more pigs than they could eat at one feast but also because they have to starve for twelve months thereafter. My contention is that it is well-nigh impossible to name a behavior (of man or any other living creature) that would not be irrational according to some normative criterion. This is precisely why to an American farmer the behavior of a Filipino peasant seems irrational. But so does the behavior of the former appear to the latter. The two live in different ecological niches and each has a different Weltanschauung. The student of man should know better than to side with one behavior or another. The most he can do is to admit that the two behaviors are different, search for the reasons that may account for the differences, and assess the consequences. (p.345ff)

Like the social insects, man lives in society, produces socially and distributes the social product among his fellows. But, unlike the social insects, man is not born with an endosomatic code capable of regulating both his biological life and his social activity. And since he needs a code for guiding his complex social activity in a tolerable manner, man has had to produce it himself. This product is what we call tradition. By tradition man compensates for his "birth defect," for his deficiency of innate social instincts. So, man is born with an endosomatic (biological) code but within an exosomatic (social) one. It is because of the endosomatic code that a Chinese, for example, has slanted eyes and straight hair. It is because of the exosomatic code that a Filipino peasant cultivates his fields in the manner all Filipino peasants do, participates in the extravagant festivals held by his village at definite calendar dates, and so on. A biological process sees to it that the pool of genes is transmitted from one generation to another. Tradition does the same for what we call "values" or, more appropriately, "institutions," i.e., the modes by which every man acts inside his own community. (p.359)

novembro 25, 2014

Bateson - Mind & Nature (1979)

[N]othing has meaning except it be seen as in some context. [...] Without context, words and actions have no meaning at all. [...] It is the context that fixes the meaning. (p.14ff)

There is a parallel confusion in the teaching of language that has never been straightened out. Professional linguists nowadays may know what's what, but children in school are still taught nonsense. They are told that a "noun" is the "name of a person, place, or thing," that a "verb" is "an action word," and so on. That is, they are taught at a tender age that the way to define something is by what it supposedly is in itself not by its relation to other things. Most of us can remember being told that a noun is "the name of a person, place, or thing." And we can remember the utter boredom of parsing or analyzing sentences. Today all that should be changed. Children could be told that a noun is a word having a certain relationship to a predicate. A verb has a certain relation to a noun, its subject. And so on. Relationship could be used as basis for definition, and any child could then see that there is something wrong with the sentence " 'Go' is a verb." (p.17)

Science sometimes improves hypotheses and sometimes disproves them. But proof would be another matter and perhaps never occurs except in the realms of totally abstract tautology. We can sometimes say that if such and such abstract suppositions or postulates are given, then such and such must follow absolutely. But the truth about what can be perceived or arrived at by induction from perception is something else again.

Let us say that truth would mean a precise correspondence between our description and what we describe or between our total network of abstractions and deductions and some total understanding of the outside world . Truth in this sense is not obtainable. And even if we ignore the barriers of coding , the circumstance that our description will be in words or figures or pictures but that what we describe is going to be in flesh and blood and action-even disregarding that hurdle of translation, we shall never be able to claim final knowledge of anything whatsoever. (p.27)

Knowledge at any given moment will be a function of the thresholds of our available means of perception. The invention of the microscope or the telescope or of means of measuring time to the fraction of nanosecond or weighing quantities of matter to millionths of a gram all such improved devices of perception will disclose what was utterly unpredictable from the levels of perception that we could achieve before that discovery. [...] Science probes; it does not prove (p.29)

All experience is subjective. (p.31)

The division of the perceived Universe into parts and wholes is convenient and may be necessary but no necessity determines how it shall be done [...] Explanation must always grow out of description, but the description from which it grows will always necessarily contain arbitrary characteristics. (p.38)

If I throw a stone at a glass window, I shall, under appropriate circumstances, break or crack the glass in a star-shaped pattern. If my stone hits the glass as fast as a bullet, it is possible that it will detach from the glass a neat conical plug called a cone of percussion. If my stone is too slow and too small, I may fail to break the glass at all. Prediction and control will be quite possible at this level. I can easily make sure which of three results (the star, the percussion cone, or no breakage) I shall achieve, provided I avoid marginal strengths of throw.

But within the conditions which produce the star-shaped break, it will be impossible to predict or control the pathways and the positions of the arms of the star. 

Curiously enough , the more precise my laboratory methods, the more unpredictable the events will become. If I use the most homogeneous glass available, polish its surface to the most exact optical flatness, and control the motion of my stone as precisely as possible, ensuring an almost precisely vertical impact on the surface of the glass, all my efforts will only make the events more impossible to predict.

If, on the other hand, I scratch the surface of the glass or use a piece of glass that is already cracked (which would be cheating), I shall be able to make some approximate predictions. For some reason (unknown to me), the break in the glass will run parallel to the scratch and about 1/100 of an inch to the side, so that the scratch mark will appear on only one side of the break. Beyond the end of the scratch, the break will veer off unpredictably.

Under tension, a chain will break at its weakest link. That much is predictable. What is difficult is to identify the weakest link before it breaks. The generic we can know, but the specific eludes us. Some chains are designed to break at a certain tension and at a certain link. But a good chain is homogeneous, and no prediction is possible. And because we cannot know which link is weakest, we cannot know precisely how much tension will be needed to break the chain. (p.41)

[G]radual growth in a population, whether of automobiles or of people, has no perceptible effect upon a transportation system until suddenly the threshold of tolerance is passed and the traffic jams. The changing of one variable exposes a critical value of the other.

A pure description would include all the facts (i.e., all the effective differences) immanent in the phenomena to be described but would indicate no kind of connection among these phenomena that might make them more understandable. For example, a film with sound and perhaps recordings of smell and other sense data might constitute a complete or sufficient description of what happened in front of a battery of cameras at a certain time. But that film will do little to connect the events shown on the screen one with another and will not by itself furnish any explanation. On the other hand, an explanation can be total without being descriptive. "God made everything there is" is totally explanatory but does not tell you anything about any of the things or their relations.

In science, these two types of organization of data (description and explanation) are connected by what is technically called tautology. Examples of tautology range from the simplest case, the assertion that "If P is true, then P is true," to such elaborate structures as the geometry of Euclid, where "If the axioms and postulates are true, then Pythagoras' theorem is true. " Another example would be the axioms, definitions, postulates, and theorems of Von Neumann's Theory of Games. In such an aggregate of postulates and axioms and theorems, it is of course not claimed that any of the axioms or theorems is in any sense "true" independently or true in the outside world.

Indeed , Von Neumann, in his famous book, expressly points out the differences between his tautological world and the more complex world of human relations . All that is claimed is that if the axioms be such and such and the postulates such and such, then the theorems will be so and so. In other words , all that the tautology affords is connections between propositions. The creator of the tautology stakes his reputation on the validity of these connections. 

Tautology contains no information whatsoever, and explanation (the mapping of description onto tautology) contains only the information that was present in the description. The "mapping" asserts implicitly that the links which hold the tautology together correspond to relations which obtain in the description. Description, on the other hand, contains information but no logic and no explanation. For some reason, human beings enormously value this combining of ways of organizing information or material. [...] An explanation has to provide something more than a description provides and , in the end , an explanation appeals to a tautology.

Now, an explanation is a mapping of the pieces of a description onto a tautology, and an explanation becomes acceptable to the degree that you are willing and able to accept the links of the tautology. If the links are "self-evident" (i.e., if they seem undoubtable to the self that is you), then the explanation built on that tautology is satisfactory to you. (p.81ff)

Information consists of differences that make a difference. If I call attention to the difference between the chalk and a piece of cheese, you will be affected by that difference, perhaps avoiding the eating of the chalk, perhaps tasting it to verify my claim. Its noncheese nature has become an effective difference. But a million other differences-positive and negative, internal and external to the chalk remain latent and ineffective.

Bishop Berkeley was right, at least in asserting that what happens in the forest is meaningless if he is not there to be affected by it.

We are discussing a world of meaning, a world some of whose details and differences, big and small, in some parts of that world, get represented in relations between other parts of that total world . A change in my neurons or in yours must represent that change in the forest, that falling of that tree. But not the physical event, only the idea of the physical event. And the idea has no location in space or time---Only perhaps in an idea of space or time. (p.99)

novembro 20, 2014

The Ethical Method

"[...] it’s remarkably common these days for people to insist that their values are objective truths, and values that differ from theirs objective falsehoods. That’s a very appealing sort of nonsense, but it’s still nonsense. Consider the claim often made by such people that if values are subjective, that would make all values, no matter how repugnant, equal to one another. Equal in what sense? Why, equal in value—and of course there the entire claim falls to pieces, because “equal in value” invites the question already noted, “according to whose values?” If a given set of values is repugnant to you, then pointing out that someone else thinks differently about those values doesn’t make them less repugnant to you. All it means is that if you want to talk other people into sharing those values, you have to offer good reasons, and not simply insist at the top of your lungs that you’re right and they’re wrong.

To say that values depend on the properties of perceiving subjects rather than perceived objects does not mean that values are wholly arbitrary, after all. It’s possible to compare different values to one another, and to decide that one set of values is better than another. In point of fact, people do this all the time, just as they compare different claims of fact to one another and decide that one is more accurate than another. The scientific method itself is simply a relatively rigorous way to handle this latter task: if fact X is true, then fact Y would also be true; is it? In the same way, though contemporary industrial culture tends to pay far too little attention to this, there’s an ethical method that works along the same lines: if value X is good, then value Y would also be good; is it? Again, we do this sort of thing all the time.

Consider, for example, why it is that most people nowadays reject the racist claim that some arbitrarily defined assortment of ethnicities — say, "the white race" — is superior to all others, and ought to have rights and privileges that are denied to everyone else. One reason why such claims are rejected is that they conflict with other values, such as fairness and justice, that most people consider to be important; another is that the history of racial intolerance shows that people who hold the values associated with racism are much more likely than others to engage in activities, such as herding their neighbors into concentration camps, which most people find morally repugnant. That’s the ethical method in practice." - John Michael Greer

novembro 18, 2014

Walter Kaufmann - The Faith of a Heretic

Kierkegaard saw that reason and philosophy were unable to tell him what idea he should choose to live and die by. Hence, he despised philosophy and reason. What he, like millions of others, overlooked is a very simple but important point: reason and philosophy may well safeguard a man against ideas for which he might better not live or die. Indeed, if reason and philosophy had no other function whatsoever, this alone would make them overwhelmingly important. (p.87)

[Theologians] resemble lawyers in two ways. In the first place, they accept books and tradition as data that it is not up to them to criticize. They can only hope to make the best of these books and traditions by selecting the most propitious passages and precedents; and where the law seems to them harsh, inhuman, or dated, all they can do is have recourse to exegesis. Secondly, many theologians accept the morality that in many countries governs the conduct of the counsel for the defense. Ingenuity and skillful appeals to the emotions are considered perfectly legitimate; so are attempts to ignore all inconvenient evidence, as long as one can get away with it, and the refusal to engage in inquiries that are at all likely to discredit the predetermined conclusion: that the client is innocent. If all else fails, one tries to saddle one's opponent with the burden of disproof; and as a last resort one is content with a reasonable doubt that after all the doctrines that one has defended might be true. (p.126)

The attempt to solve the problem of suffering by postulating original sin depends on the belief that cruelty is justified when it is retributive; indeed, that morality demands retribution. (p.172)

The crucial point that should never be forgotten in the history of ideas can be put into a single sentence: one may have been influenced profoundly by others and yet be strikingly original and even revolutionary. (p.183)

In India, the Jina and Buddha, founders of two new religions in the sixth century BC, came to be worshiped later by their followers. In China, Confucius and Lao-tze came to be deified. To the non-Christian, Jesus seems to represent a parallel case. In Egypt, the Pharaoh was considered divine. In Israel, no man was ever worshiped or accorded even semi-divine status. This is one of the most extraordinary facts about the religion of the Old Testament and by far the most important reason for the Jew's refusal to accept Christianity and the New Testament. [...] Why, then, was Moses never defied or worshiped? The most obvious explanation is that he himself impressed his people with the firm idea that no human being is divine in any sense in which the rest of mankind isn't. (p.220)

According to the Gospels, Jesus' conception of salvation was radically otherworldly [...] The perspective of the prophets was reversed. They, too, had taught humility and love, but not this preoccupation with oneself. The accent had been on the neighbor and the stranger, the orphan, the widow, and the poor. Social injustice cried out to be rectified and was no less real because it meant a lack of love and a corruption of the heart. Man was told to love others and to treat them justly -- for their sake, not of his own, to escape damnation. To the Jesus of the Gospels, social injustice as such is of no concern. Heaven and hell-fire have been moved into the center. (p.221)

Consider the rich man who, according to Luke (18:18ff), asked Jesus the identical question [How to inherit eternal life?]. To him, Jesus cites five of the Ten Commandments before adding: "One thing you still lack. Sell all you have and distribute it to the poor, and you will have treasure in heaven; and come, and follow me." It is no longer the poor that require love and justice; it is the giver who is to accumulate treasure in heaven. The social order, with which Moses and the prophets were centrally concerned, counts for nothing; the life to come is everything. If what truly matters is treasure in heaven, what do the poor gain from what they are given? (p.222)

The Pharisees had tried to build what they themselves called "a fence around the Law" -- for example, by demanding that the observation of the Sabbath should begin a little before sunset, to guard against trespasses. It might seem that Jesus, in the sermon of the Mount, was similarly erecting a fence around morality. For he introduces his most extreme demands: "Till heaven and earth pass away, not a iota, not a dot, will pass from the law until all is accomplished. Whoever then relaxes one of the least of these commandments and teaches men so, shall be called least in the kingdom of heaven... Unless your righteousness exceeds that of the scribes and Pharisees, you will never enter the kingdom of heaven." Then Jesus goes on to say that it is not enough not to kill: "Whoever says, 'You fool!' shall be liable to hell fire." It is not sufficient not to commit adultery, nor not to covet one's neighbor's wife, but "every one who looks at a woman lustfully has already committed adultery with her in his heart". On reflection, the old morality is not protected but undermined, not extended but dissolved; and no new morality is put in its place. Where murder is not considered importantly different from calling a man a fool, nor adultery from a lustful look, the very basis of morality is denied: the crucial distinction between impulse and action. If one is unfortunate enough to have the impulse, no reason is left for not acting on it. (p.226)

[...] we confront the objection that faith and morals are quite different [...] men of different faiths can live together in peace, provided they agree on standards of behavior; but without moral agreement men cannot live together in peace. This objection is half-true but quite insufficient to establish any absolute morality. Where there is much traffic, there have to be traffic rules to avoid needless injuries and deaths and to ensure the attainment of the purposes of traffic. There has to be an agreement on what side of the road one is supposed to drive. It does not matter whether the rule is to drive on the right or on the left; what matters is that everybody should follow the same rule. [...] it would be silly to insist that driving on the right is absolutely preferable, true or moral, while driving on the left is absolutely false and immoral. To live together peacefully, men need rules, and these rules may even have to be enforced, if all else fails, with penalties. It does not follow that these rules are absolutely right or that every act that conflicts with a rule, even if the rule should be important, is immoral in some absolute sense, unless, of course, we define immorality as violations of mores, of conventions -- as non-conformity. (p.311)

Most discussions of morality rest on the false assumption that 'moral' have one single central meaning. [...] Agreement that stealing is immoral may be comparable to a case in which five men refuse to eat beef and warn others not to eat it either: the first does not like the taste and either does not believe that taste differ or, admitting that they do, considers his own taste the only 'true' one. The second one loves the taste but wants to punish himself; and he too thinks that what is right for him is right for others. The third thinks that meat is poisonous or dangerous. The fourth is a Hindu. The fifth, who is not a Hindu, is a vegetarian. Their superficial agreement is not altogether unimportant. As long as they do not enter into questions of meaning, faith, or morals, they may get along; and they may even suppose erroneously that they agree on certain facts -- absolutely true facts -- which moral idiots who eat beef deny. (p.313)

Some people think moral disagreements are like disagreements about facts; others claim they are like differences of taste. Actually, moral judgments are almost invariably elliptical [ie, they miss relevant information], and when they are spelled out they are found to involve all kinds of assumptions about facts as well as an element of taste. And moral disagreements generally involve disagreements about facts, differences in taste, or both. Spelling out the factual disagreements may at times dispel a moral disagreement; but even when it does not, it will generally lead to a drastic reduction of heat. (p.315)

An ethic cannot be proved; to be held responsibly, it has to be based on encounter upon encounter. This notion of encounter is of the most philosophic importance. It makes possible safe passage between the untenable claim of proof and the unwarranted charge of irrationality. A position may be rational through it cannot be deduced from universally accepted premises, and a man may be rational without claiming that his views, his ethic, or his faith are susceptible of such proof. The pose of Socrates, always willing to subject any view to objections, was that of the rational man par excellence. (p.333)

Negative thinking is what save us from relativism. One has to show why alternatives are untenable. (p.334)

A man who does not consider how his actions are likely to affect other people is to that extent irresponsible, even if he acts on 'principle'. Moral judgments on specific actions are also irresponsible insofar as they are passed in ignorance of the background, the interests involved, and the probable consequences -- even if such judgments appeal to 'principle'. The principles themselves may be held in a more or less informed, responsible, rational manner. To be responsible and rational in such matters, one must consider what can be said against one's moral principles and standards. The man who gives no thought to objections and alternatives is, to that extent, irrational. (p.335)

novembro 13, 2014


De todos os métodos filosóficos, a comparação é o mais fidedigno. Comparar gestos, atitudes, comparar a viabilidade e o benefício, a linguagem e a coerência. Há quem diga que é impossível comparar, que uma situação é sempre incomparável. Parece-me uma subtileza que esconde uma cobardia. Pedro Mexia

novembro 10, 2014

Truth had never been a priority

All those gut feelings, right or wrong, that had kept the breed alive on the Pleistocene savannah—and they were wrong, so much of the time. False negatives, false positives, the moral algebra of fat men pushed in front of onrushing trolleys. The strident emotional belief that children made you happy, even when all the data pointed to misery. The high-amplitude fear of sharks and dark-skinned snipers who would never kill you; indifference to all the toxins and pesticides that could. The mind was so rotten with misrepresentation that in some cases it literally had to be damaged before it could make a truly rational decision—and should some brain-lesioned mother abandon her baby in a burning house in order to save two strangers from the same fire, the rest of the world would be more likely to call her a monster than laud the rationality of her lifeboat ethics. Hell, rationality itself—the exalted Human ability to reason—hadn’t evolved in the pursuit of truth but simply to win arguments, to gain control: to bend others, by means logical or sophistic, to your will. Truth had never been a priority. If believing a lie kept the genes proliferating, the system would believe that lie with all its heart. Peter Watts - Echopraxia

novembro 06, 2014

Invisible Tigers

[...] fifty thousand years ago there were these three guys spread out across the plain, and they each heard something rustling in the grass. The first one thought it was a tiger, and he ran like hell, and it was a tiger but the guy got away. The second one thought the rustling was a tiger, and he ran like hell, but it was only the wind and his friends all laughed at him for being such a chickenshit. But the third guy, he thought it was only the wind, so he shrugged it off and a tiger had him for dinner. And the same thing happened a million times across ten thousand generations — and after a while everyone was seeing tigers in the grass even when there weren’t any tigers, because even chickenshits have more kids than corpses do. And from those humble beginnings we learned to see faces in the clouds and portents in the stars, to see agency in randomness, because natural selection favors the paranoid. Even here in the twenty-first century you can make people more honest just by scribbling a pair of eyes on the wall with a Sharpie. Even now, we are wired to believe that unseen things are watching us. 

 And it came to pass that certain people figured out how to use that. They painted their faces or they wore funny hats, they shook their rattles and waved their crosses and they said, Yes, there are tigers in the grass, there are faces in the sky, and they will be very angry if you do not obey their commandments. You must make offerings to appease them, you must bring grain and gold and altar boys for our delectation or they will strike you down and send you to the Awful Place. And people believed them by the billions, because after all, they could see the invisible tigers. Peter Watts - Echopraxia

novembro 03, 2014

"Justiça Fiscal", JL Saldanha Sanches

Constitucionalizar um princípio é a forma contemporânea de tentar sacralizar e eternizar um valor considerado imperecível. Claro que já não é possível, e está longe dos diagramas de força que regem as sociedades actuais, a possibilidade de produzir uma nova versão dos Dez Mandamentos bíblicos, mesmo para fins a que hoje chamaríamos estritamente laicos. Não quer isto dizer que uma Constituição, tal como sucede com as nossas, não deva ter uma durabilidade mínima, pois a flexibilidade patológica constitui um forte elemento de deslegitimação.

A defesa dos direitos fundamentais, se for feita por meio de regras sujeitas a permanentes alterações, equivale a uma espécie de baluarte móvel, ou seja, uma contradição dos seus termos na defesa das garantias do sujeito passivo no Estado constitucional. A alteração essencial, feita por meio da ruptura com um anterior texto normativo, deverá caber ao trabalho do juiz ou, em termos mais amplos, da jurisprudência. Não temos valores jurídicos eternos e imutáveis e não podemos conceber princípios para todo o sempre, mas a mudança e construção de novas interpretações num texto constitucional são uma tarefa a realizar de forma comunitária pelos juristas e cidadãos, maxime pelos tribunais. (pg. 29)

As leis fiscais estão sempre sujeitas a um processo de discussão pública, uma vez que devem ser aprovadas pelo Parlamento, podendo a opinião pública facilmente reagir a movimentos perceptíveis de maior oneração fiscal quando o executivo se vê obrigado a aumentar impostos. 

No entanto, para além destas grandes decisões perceptíveis (por exemplo, quando a taxa do IVA aumenta 2 pp) a lei fiscal está sempre cheia de um conjunto de pequenas excepções, de regimes especiais, de benefícios fiscais que, ainda que no seu cômputo final alterem profundamente a distribuição da carga tributária, escapam quase sempre à percepção da grande maioria dos contribuintes. São excepções que estilhaçam a lógica interna do sistema e os princípios de oneração, são um conjunto de «contranormas» que o contribuinte normal percebe mal, mas que lhe transmitem a noção (exacta) de que as leis fiscais são injustas.

Estas sistemáticas criações de nichos de privilégio mediante a acção de lobistas foram minuciosamente estudadas nos EUA onde a enorme complexidade do tax code tem sido explicada por uma intensíssima e permanente interacção entre legisladores e interesses particulares. (pg.43)

Os benefícios fiscais [isenções] são uma excepção à regra da tributação [...] A desigualdade de tratamento entre factos semelhantes com alguns excluídos de tributação exige uma justificação, sob pena de um regresso aos privilégios fiscais. Tal justificação pode ser de ordem económica ou social. [...] Em todos estes casos poderemos encontrar razões para a atribuição de um regime fiscal mais favorável, mas a multiplicações destas razões -- e a consequente multiplicação de benefícios fiscais (que depois de serem concedidos tendem a perpetuar-se independentemente de um juízo renovado sobre a sua real eficácia) -- é um dos problemas principais dos sistemas fiscais de hoje.

Numa lógica liberal que se opõe à intervenção do Estado na economia, a atribuição de benefícios fiscais não deverá existir, ou, pelo menos, deverá ser desempenhada por subsídios. Em relação às consequências financeiras, o custo do subsídio é o mesmo que a receita perdida em virtude do benefício fiscal, com a vantagem de ser mais transparente e de a sua atribuição dever ser decidida todos os anos, orçamento após orçamento. (pg.49)

Os impostos sobre os combustíveis são a negação de tudo aquilo que aprendemos sobre a justiça fiscal: aumentando o preço da gasolina ou do gasóleo atingem-se principalmente os contribuintes com menor capacidade contributiva, cidadãos estes que podem ser obrigados a mudar de comportamento -- abandonar o uso do automóvel -- quando o imposto se junta ao aumento do preço do produto-base. E, no entanto, tudo visto e ponderado, estes impostos são justos. Mas justos em que sentido? 

Ao internalizar as externalidades negativas ligadas ao uso dos combustíveis fósseis, o imposto sobre os combustíveis amplifica um sinal que o mercado transmite de forma insuficiente: a necessidade de poupar energia por, nesta área, as flutuações do preço não conduzirem a uma situação de equilíbrio. Não conduzem, porque, a curto e médio prazo, os combustíveis fósseis são o método mais económico de produzir energia. Mas apenas a curto e médio prazo, e porque não se contabilizam os custos ambientais. [...] a inacção do Estado, com a ausência de políticas públicas sobre energias alternativas e a manutenção do petróleo para consumo interno a preços agradavelmente baixos, ainda que socialmente pareça justa, tem efeitos geopolíticos inaceitáveis [...] os argumentos ligados à eficiência económica e social desta tributação são tão fortes que se tornam um argumento de justiça. (pgs 69-71)

outubro 27, 2014

Now, consciousness. That's a fun thing, isn't it? Product of an arms race between predators and prey. If you watch a cat creeping up on a mouse, you'll be able to impute to the cat intentions that are most easily explained by the cat having a theory of mind concerning the mouse – an internal simulation of the mouse's likely behavior when it notices the predator. Which way to run, for example. And the cat will use its theory of mind to optimize its attack strategy. Meanwhile, prey species that are complex enough to have a theory of mind are at a defensive advantage if they can anticipate a predator's actions. Eventually this very mammalian arms race gave us a species of social ape that used its theory of mind to facilitate signaling – so the tribe could work collectively – and then reflexively, to simulate the individual's own inner states. Put the two things together, signaling and introspective simulation, and you've got human-level consciousness, with language thrown in as a bonus – signaling that transmits information about internal states, not just crude signals such as 'predator here' or 'food there.' -- Charles Stross, Accelerando

setembro 22, 2014

Orthogonal quotes

"What happens, happens," Carla offered gnomically. "Everything in the Cosmos has to be consistent. All we get to do is talk about it in a way that makes sense to us"


[...] imagine the time when wave mechanics powers every machine and everyone takes it for granted. Do you really want them thinking that it fell from the sky, fully formed, when the truth is that they owe their good fortune to the most powerful engine of change in the history: people arguing about science.


The cosmos is what it is. The laws of optics and mechanics and gravity are simple and elegant and universal... but a detailed description of all the things on which those laws play out seems to be nothing but a set of brute facts that need to be discovered individually. I mean, a 'typical' cosmos, in statistical terms, would be a gas in thermal equilibrium filling the void, with no solid objects at all. There certainly wouldn't be steep entropy gradients. We've only be treating the existence of such gradient as a 'law' because it was the most prominent fact in our lives: time came with a arrow distinguishing the past from the future.

Greg Egan, Orthogonal (books II & III)

setembro 01, 2014

Primitive man, aware of his helplessness against the forces of Nature but totally ignorant of their causes, would try to compensate for his ignorance by inventing hypotheses about them [...]  For one who has no comprehension of physical law, but is aware of his own consciousness and volition, the natural question to ask is not: "What is causing it?", but rather: "Who is causing it?"  [...] The error [Mind Projection Fallacy] occurs in two complementary forms, which we might indicate thus: (a) My own imagination => Real Property of Nature, and (b) My own ignorance => Nature is indeterminate.

The philosophical dierence between conventional probability theory and probability theory as logic is that the former allows only sampling distributions, interprets them as physically real frequencies of "random variables", and rejects the notion of probability of an hypothesis as being meaningless. We take just the opposite position: that the probability of an hypothesis is the fundamental, necessary ingredient in all inference, and the notion of "randomness" is a red herring, at best irrelevant. [...] by "probability theory as logic" we mean nothing more than applying the standard product and sum rules of probability theory to whatever propositions are of interest in our problem.

We do not seek to explain "statistical behavior" because there is no such thing; what we see in Nature is physical behavior, which does not conflict in any way with deterministic physical law.

[...] as in any other problem of inference, we never ask, "Which quantities are random?" The relevant question is: "Which quantities are known, and which are unknown?"

agosto 24, 2014

"He never sees [Thomas] More – a star in another firmament, who acknowledges him with a grim nod – without wanting to ask him, what's wrong with you? Or what's wrong with me? Why does everything you know, and everything you've learned, confirm you in what you believed before? Whereas in my case, what I grew up with, and what I thought I believed, is chipped away a little and a little, a fragment then a piece and then a piece more. With every month that passes, the corners are knocked off the certainties of this world: and the next world too. Show me where it says, in the Bible, ‘Purgatory’. Show me where it says relics, monks, nuns. Show me where it says ‘Pope’." 

"[...] it is no use to justify yourself. It is no good to explain. It is weak to be anecdotal. It is wise to conceal the past even if there is nothing to conceal. A man's power is in the half-light, in the half-seen movements of his hand and the unguessed-at expression of his face. It is the absence of facts that frightens people: the gap you open, into which they pour their fears, fantasies, desires."

Wolf Hall, Hilary Mantel

maio 25, 2014

In the eye of the beholder

"Neither good nor ill is done to us by Fortune: she merely offers us the matter and the seeds: our soul, more powerful than she is, can mould it or sow them as she pleases, being the only cause and mistress of our happy state or our unhappiness. Whatever comes to us from outside takes its savour and its colour from our internal attributes, just as our garments warm us not with their heat but ours, which they serve to preserve and sustain. Shelter a cold body under them and it will draw similar services from them for its coldness: that is how we conserve snow and ice. Study to the lazy, like abstinence from wine to the drunkard, is torture; frugal living to the seeker after pleasure, like exercise to the languid idle man, is torment: so too for everything else. Things are not all that painful nor harsh in themselves: it is our weakness, our slackness, which makes them so. To judge great and lofty things we need a mind which is like them: otherwise we attribute to them the viciousness which belongs to ourselves. A straight oar seems bent in water. It is not only seeing which counts: how we see counts too." Essay XIV, "That the taste of good and evil things depends in large part on the opinion we have of them", Michel de Montaigne

maio 21, 2014


maio 18, 2014


"In plain truth, lying is an accursed vice. We are not men, nor have other tie upon one another, but by our word. If we did but discover the horror and gravity of it, we should pursue it with fire and sword, and more justly than other crimes. I see that parents commonly, and with indiscretion enough, correct their children for little innocent faults, and torment them for wanton tricks, that have neither impression nor consequence; whereas, in my opinion, lying only, and, which is of something a lower form, obstinacy, are the faults which are to be severely whipped out of them, both in their infancy and in their progress, otherwise they grow up and increase with them; and after a tongue has once got the knack of lying, 'tis not to be imagined how impossible it is to reclaim it whence it comes to pass that we see some, who are otherwise very honest men, so subject and enslaved to this vice. I have an honest lad to my tailor, whom I never knew guilty of one truth, no, not when it had been to his advantage. If falsehood had, like truth, but one face only, we should be upon better terms; for we should then take for certain the contrary to what the liar says: but the reverse of truth has a hundred thousand forms, and a field indefinite, without bound or limit. The Pythagoreans make good to be certain and finite, and evil, infinite and uncertain. There are a thousand ways to miss the white, there is only one to hit it." -- Essays IX, "Of Liars", Michel de Montaigne

janeiro 31, 2014

Unwelt II

"In 1909, the biologist Jakob von Uexküll introduced the concept of the umwelt. He wanted a word to express a simple (but often overlooked) observation: different animals in the same ecosystem pick up on different environmental signals. In the blind and deaf world of the tick, the important signals are temperature and the odor of butyric acid. For the black ghost knifefish, it's electrical fields. For the echolocating bat, it's air-compression waves. The small subset of the world that an animal is able to detect is its umwelt. The bigger reality, whatever that might mean, is called the umgebung. The interesting part is that each organism presumably assumes its umwelt to be the entire objective reality "out there." Why would any of us stop to think that there is more beyond what we can sense?" David M. Eagleman