Escalas 1:1 antes de Jorge Luís Borges

‘That’s another thing we’ve learned from your Nation,” said Mein Herr, “map-making. But we’ve carried it much further than you. What do you consider the largest map that would be really useful?”

“About six inches to the mile.”

“Only six inches!” exclaimed Mein Herr. “We very soon got to six yards to the mile. Then we tried a hundred yards to the mile. And then came the grandest idea of all! We actually made a map of the country, on the scale of a mile to the mile!”

“Have you used it much?” I enquired.

“It has never been spread out, yet,” said Mein Herr: “the farmers objected: they said it would cover the whole country, and shut out the sunlight! So we now use the country itself, as its own map, and I assure you it does nearly as well.”

Lewis Carroll, Sylvie and Bruno Concluded, 1893

Os Despojados II

• It is of the nature of idea to be communicated: written, spoken, done. The idea is like grass. It craves light, likes crowds, thrives on crossbreeding, grows better for being stepped on.
• It is hard, however, for people who have never paid money for anything to understand the psychology of cost, the argument of the marketplace.
• You can’t crush ideas by suppressing them. You can only crush them by ignoring them. By refusing to think, refusing to change.
• What drives people crazy is trying to live outside reality. Reality is terrible. It can kill you. Given time, it certainly will kill you. The reality is pain [...] But it’s the lies, the evasions of reality, that drive you crazy.
• The individual cannot bargain with the State. The State recognizes no coinage but power: and it issues the coins itself.
• We came from a great distance to each other. We have always done so. Over great distances, over years, over abysses of chance. It is  because he comes from so far away that nothing can separate us. Nothing, no distances, no years, can be greater than the distance that's already between us, the distance of our sex, the difference of our being, our minds; that gap, that abyss which we bridge with a look, with a touch, with a word, the easiest thing in the world.

Ursula K. LeGuin -- The dispossessed

Os despojados I

"“It exists,” Shevek said, spreading out his hands. “It’s real. I can call it a misunderstanding, but I can’t pretend that it doesn’t exist, or will ever cease to exist. Suffering is the condition on which we live. And when it comes, you know it. You know it as the truth. Of course it’s right to cure diseases, to prevent hunger and injustice, as the social organism does. But no society can change the nature of existence. We can’t prevent suffering. This pain and that pain, yes, but not Pain. A society can only relieve social suffering, unnecessary suffering. The rest remains. The root, the reality. All of us here are going to know grief; if we live fifty years, we’ll have known pain for fifty years. And in the end we’ll die." Ursula K. LeGuin -- The dispossessed

Inevitabilidade

Temos um problema catastrófico nas fontes da economia global -- recursos, energia -- e nos seus escoadouros -- poluição, aquecimento global. De que forma e quão profundamente as nossas soluções para os direitos económicos e políticos -- capitalismo, democracia -- terão de se transformar para serem capazes de verdadeiramente atacar esta questão? 

Ontology & Epistemology

I tend to gravitate around "the Map is not the Territory" concept in the ontology/epistemology discussion. I understand «territory» as the event generator, aka reality. We are only able to measure events indirectly using our senses and tech (events with no effects are non-existent for all purposes). The 'map' is a tangled web of shared and private beliefs that we, Humanity, build and maintain for centuries. The «Map» is the meaning generator (I'm dropping the guillemets now).

The terms objective/subjective imho only make sense in the Map. Objective beliefs are those not dependent of personal mind states, and those dependent are subjective (this is more like a spectrum than a boolean feature, but let's keep it simple). Beliefs not dependent of private or social features (even if they are known just because of specific historical contexts) and which are known using logic/evidence/reason are (more) objective like Math. This does not mean that objective beliefs are necessarily 'true' (it depends on the semantics of the word 'true') but they are not, or should not be, dependent of persons X's or Y's state of mind. This also does not mean that objective beliefs are necessarily better than subjective ones (that requires a value judgement which is context-dependent). Anyway, this is why I think that, say, my liking of ice-cream is subjective. That is a private belief that would not exist if I would not exist. It depends of my current mind state. On the other hand, the theory of evolution by natural selection or the Central Limit Theorem are beliefs that do not depend on any person's mind. But, either objective or subjective, all are map denizens. Even scientific models are just that: maps; not intrinsically true or false, just more or less adequate to the known relevant evidence and current knowledge. 

However this way of classifying beliefs is just one way not the way. Thinking about the divide between public or private beliefs is as important as seeing them as objective or subjective (Ethics and Politics seems a much more interesting and important subject that Ontology and Epistemology but that's my perspective). 

One more thing: in a subtle way, every belief belongs to the Territory -- human beliefs are caused by certain neuro-electric impulses, and those are measurable events -- which is a trivial fact and not that interesting (even if it is important, because it protects this model of ontology against the charge of dualism, the Map is not independent of the Territory). The meaning of those brain impulses only makes sense in the Map. Without humans -- the makers and keepers of the Human Map -- the only thing that would exist would be the physical phenomena that we label with words and inject with meaning. Without a 'Map' there would be no stars, no colors or sounds, no art or philosophy or love. There would only exist 'meaningless indifferent stuff' (for lack of better words).

Alternatives

Evidence for a model (or belief) must be considered against alternative models. Let me describe a neutral (and very simple) example: Assume I say I have Extra Sensorial Perception (ESP) and tell you that the next dice throw will be 1. You throw the dice and I was right. That is evidence for my claim of ESP. However there's an alternative model ('just a lucky guess') that also explains it and it's much more likely to be the right model (because ESP needs much more assumptions, many of those in conflict with accepted facts and theories). This is a subject of statistical inference. It's crucial to consider the alternatives when we want to put our beliefs to the test.

Unpacking faith

Guy Plowman: "I have faith in science because it has been consistently useful in helping me to navigate the physical universe." 

Don't you have instead confidence in Science? I think sometimes we overuse the word 'faith'. Eg, I don't have faith in my wife, I trust her. I don't have faith in my daughter's future, I hope she'll do fine. I prefer to reserve 'faith' where it's used to describe that belief that gets stronger especially when the evidence is overwhelming against it. Let me quote Jesus on this one: "I assure you, if you have faith and don't doubt, you can do things like this and much more. You can even say to this mountain, `May God lift you up and throw you into the sea,' and it will happen." (Matthew 21:21) That's the faith I'm talking about!

Never ending stories

Arguments and topics that consider data as irrelevant become exercises is Aesthetics, which is not intrinsically bad but might turn into a never ending discussion. On the other hand, I'm not sure we should easily dismiss a good argument that goes against current evidence. Perhaps the evidence is not good enough, and the argument can show new ways to search for new knowledge. Heliocentrism comes to mind.

Reification

Colors are in the eye of the beholder. For a bat-like agent there are no colors. However, for him there are sonar textures that he would also consider universal properties of the world. Colors, sounds, smells are just names describing the different ways our primate brains process sense data. Which, by the way, is an amazingly restricted subset of all possible data that can be sensed. Something similar happens with numbers. What I see as one wall, another sees a lattice of bricks (are lattices also universal properties?). What we see as one person, a virus «sees» as a population of cells with no well-defined boundary.

Livre Arbítrio e Dores de Cabeça

O que têm as dores de cabeça a ver com o livre arbítrio? Ora bem, eu tenho uma valente dor de cabeça e estou em casa, em silêncio, na esperança dela se ir embora. Tocam à porta. É o meu vizinho a pedir-me uma cebola para o refogado. Falo da maleita que me aflige e logo começa a argumentar que as dores de cabeça não existem. Elas não são detectadas nas ressonâncias magnéticas, não existem modelos científicos que as justificam (imaginemos que é verdade) e etc e tal. É uma ilusão, afirma. E assim aplica todo o seu arsenal argumentativo e o vasto conhecimento científico sobre o assunto (imaginemos que é neurologista) nesta sua posição. O que ganho com tudo isto para além de me aumentar ainda mais a dor de cabeça?

Uma dor de cabeça pode ser um fenómeno 100% mental, uma forma da mente interpretar um determinado estado do cérebro ou nem isso. O que significa afirmar que as dores de cabeça não existem porque não interagem, para todos os efeitos práticos, com o mundo exterior? Se eu acredito que tenho uma dor de cabeça, não me faz isso ter uma dor de cabeça? O que se pode argumentar contra o óbvio da própria experiência mental de ter uma dor de cabeça?

É-me atraente fazer a analogia com o livre arbítrio. Se o livre arbítrio for também ele um fenómeno 100% mental, se eu achar que o tenho não me faz isso tê-lo? Estas duas situações são totalmente diferentes de afirmar que se eu acho que compreendo Teoria Quântica então eu sei Teoria Quântica. Nos primeiros casos apenas é necessário introspeção. No caso da Teoria Quântica é necessário validação. Lá por me convencer que compreendo os fundamentos da Física subatómica não significa que consiga desenvolver investigação na área ou sequer resolver os exercícios mais simples de um livro introdutório sobre o assunto. A convicção de eu saber algo sobre o mundo externo só é justificável se realmente for capaz de interagir em conformidade com as crenças que alimento.

Mas isso não acontece tanto na dor de cabeça como no livre arbítrio. Pelo contrário, sendo processos inteiramente introspetivos, que ocorrem e só fazem sentido no interior de cada mente, dificilmente o mundo externo tem algo a dizer sobre o assunto. Para o mundo exterior, saber se um agente acredita que tem livre arbítrio apenas é relevante como informação que ajuda a explicar ou a prever o seu comportamento. Em termos ontológicos esta crença, bem como a de ter dores de cabeça, é inconsequente, nada adiciona nada retira.

O cartoon seguinte poderá fazer sentido do ponto de vista externo, mas não do ponto de vista interno. As únicas ilusões que eu posso alimentar são ilusões sobre o que se passa lá fora. Cá dentro, no labirinto de crenças internas que alimento e me alimenta, a crença de ter algo -- uma dor de cabeça, medo das alturas, amor à minha família, ansiedade, nostalgia, livre escolha -- é esse algo.

Provincianismo

Saturday Morning Breakfast Cereal

Mathematical realism

Mathematical realism defends that mathematical objects have independent existence outside minds. In this view, mathematics is more about discovering an unknown world than just creating formal coherent maps. This position seems to me an indisputable matter of principle, an aesthetic position that cannot be decided, a modern version of the ancient theory of Plato's forms.

Math is the paradigm of objective knowledge but I feel suspicious when that is used to imply their external existence. Beliefs can be objective or subjective but how can that tell us anything about external reality? An objective belief is a belief that does not depend on the agent's state of mind, but a belief nonetheless It does not directly follow that without minds objective beliefs would still exist (or could exist even before minds). What are the arguments to justify this step?

Another way to argue is to state the uncanny usefulness of mathematics. Some math models are surprisingly useful for science. However, there are potentially an infinity of different mathematical models. In our finite world we will always use an infinitesimal fraction of the mathematical formal structure. So, usefulness does not seem a strong argument in the defense of math realism: most of Math would be useless to explain a finite Universe (not enough world to use all those theorems).

Even restricting the realm of 'real' Math like Kronecker did when he said God made the natural numbers; all else is the work of man does not make things easier. In some alien world, the subset of Math they'll use may be very different from our own. Eg, in a plasma world -- where everything would be in flux and no solids would exist -- natural numbers (0,1,2...) might not make the least practical sense for its inhabitants and they would be as known to the average plasma-mind as manifold theory is to our carbon-minds. So, even those most basic of math concepts, like naturals, might not be as natural as we think they are. And stating that Human «natural Math» is the one that is «real» seems just provincialism.

Original posting & discussion: https://plus.google.com/u/0/107157321007785956289/posts/4abeMMDY2Qx

Saturday Morning Breakfast Cereal

Fora do circuito

Fora da academia, do que é considerado conhecimento estabelecido, há um grande conjunto de obras de variado valor. A história da ciência, da filosofia e da matemática mostra variados exemplos de pessoas que defenderam ideias fora do sistema, tendo algumas delas sido ostracizadas e até levadas ao suicídio, cujas ideias que defendiam vingaram e tornaram-se respeitadas e até mesmo no próprio sistema. Casos como os infinitos de Cantor, a interpretação estatística da Termodinâmica de Boltzmann ou as ideias de Nietzsche são disto bons exemplos.

Mas será arrogante assumir que o desenvolvimento do conhecimento humano não tem falsos positivos (ideias vigentes que não são as melhores entre as disponíveis) e falsos negativos (ideias erradamente rejeitadas por preconceito, desconhecimento ou falta de evidência). Entre os falsos positivos destacam-se, a meu ver, a Economia Clássica (com o seu axioma do agente racional já falsificado empiricamente, eg, cf. Kahneman, Thinking Fast and Slow) e a Estatística Clássica, onde o principal adversário, a Inferência Bayesiana, teve um renascimento com o advento dos computadores mas que continua persona non grata da academia (era pior há umas décadas). Entre os falsos negativos ficaremos, em alguns casos, na eterna dúvida se um dado autor teria mesmo razão, no sentimento vago de estarmos a perder alguma coisa importante. Claro que um sistema conceptual recusado não possa ser resgatado parcialmente. A sociedade pode absorver parcelas que as torna suas, sem ter de digerir a totalidade do que o respectivo autor defendeu. 

Entre os autores destes potenciais falsos negativos encontro especial interesse nos seguintes:

Julian Jaynes: The origin of consciousness in the breakdown of the bicameral mind. Neste livro é defendida uma tese que o nascimento da consciência humana é um fenómeno historicamente recente (por volta da Grécia Antiga, entre Homero e Péricles) e que os humanos anteriores a essa época ainda não eram pessoas. Não consigo fazer juz ao livro mas é muito interessante e bem escrito, e como seria interessante perceber que Jaynes afinal tinha tido razão!

Thomaz Szasz: The Myth of Mental Illness (entre outros livros deste autor). Szasz é um médico que há décadas critica a forma como a profissão psiquiátrica categoriza a doença mental. Em parte, algumas das suas teses foram absorvidas pelo mainstream, sendo provável que a sua posição actual seja mais extremada do que justificariam os procedimentos actuais. Apesar disso uma consulta à DSM, que classifica por exemplo o travestismo  como doença mental, nos deixe a pensar que talvez ainda haja muito trabalho a fazer nesta frente.

Alfred Korzybski: Science and Sanity. É deste livro que vem o aforismo "o mapa não é o território" e a sistematização da ideia que as teorias e conceitos humanos não têm existência para lá de nós mesmos. De certa forma, apesar da ostracização que sofreu (o livro é realmente um bocado alucinado) estas ideias vingaram e são muito presentes na nossa cultura. Hoje em dia é mais fácil afirmar que uma teoria é «apenas» o mapa de um padrão reconhecido do que fora no passado. Não esqueçamos que no início do século XX ainda se discutia ao mais alto nível científico se a luz tinha uma natureza corpuscular ou ondulatória, como se a luz fosse realmente ou uma partícula ou uma onda.

Teatro

The Universe is a messy and dangerous place. Fitness is not an optional policy in the natural selection perpetual genocide. The successful life-and-death stories of our ancient primate ancestors were imprinted in our genes. They still partially define, even today in our complex social world, what 'human' means. Our brains and bodies have default mechanisms that shape and limit our cognitive abilities, our ability to learn and remember, to reason and feel, to introspect. What we recognize as 'I'.

For fitness sake, the evolution of our actions, our behavior, converged to pursue (desire) certain sensations -- feelings, brain states -- and avoid (fear) others. Two examples are sexual arousal and pain, respectively. We are able to learn that different contexts favor different sensations. We adapt and manage our desires and fears to serve the multilayered goal of survival (multilayered in the sense of being made of several, more specific sub-goals but also for having multiple and not necessarily compatible solutions).

One powerful factor in this emotional and sensorial ecosystem is society. Society inhibits or enhances sensations, desires and goals through social conditioning not necessarily concerned with individual survival. One example is how nationalism is able to transfer and corrupt the genetic instincts of family into social norms to better serve the preservation of a national concept. However, this reshaping is not arbitrary, since it is impossible to remove our primitive genetic behavioral heritage without losing the person within. Humans minds are elastic but they are not blank slates. The resulting individual behavior turns out to be quite subtle in complex societies, forcing part of our genetic past into sleep mode, hardly detected in normal, non stressful situations. Herein, we are not that different from most social mammals.

But we humans are not satisfied with just that. Humans are active believers, constantly inserting meaning into the world stuff and into the mind stuff. We are addicted to belief and cannot help ourselves. One important side effect is value. A value is determined by the desire/fear intensity for a certain sensation. It is natural for us to classify a goal towards a attractive (repulsive) sensation has having a good (bad) value. And then that goal's value contaminates the cognitive architecture: a good (bad) goal must come from virtuous (vicious) desires and promotes right (wrong) actions. We elaborate enormous cognitive structures around the value concept. Ethics, Politics and Religion are basically arguments -- logical, empirical, traditional, dogmatic arguments -- to shape how values, virtues and righteousness are mapped. We feel that something has value, that acting such and such is right, but these are just instances of the mind projection fallacy. They are the result of our unrestrained use of meaning inception. They are internal mind attributes not external features of those somethings. We do not avoid something because it is bad, we define as bad those things we want to avoid.

This does not imply that meaning is arbitrary or relative. We are social animals after all, and share sensations, desires, goals. Our biology and cognitive apparatus is the same. So, at least for homo sapiens, this mapping does not have that much variability. Pain, say, is intrinsically a sensation to avoid. It is no surprise that violence towards other humans is usually considered a wrong action or that, for promoting violence, political and religious leaders choose first to dehumanize the enemy.

And where is consciousness in all this? Consciousness is not necessary for this sensation/desire/goal structure nor for the resulting behavior. Many different animals seem to be equipped with them and still don't seem to possess consciousness. Also, consciousness is not necessary for choice. A simple mechanism is able to make choices when faced with multiple options (even a thermostat has capacity for binary choice). A choice is the process of selecting an action among possible actions. It can be described in algorithmic terms (one classical definition is the maximization of expected utility) and, at least in its basic form, does not need cognition. However, perhaps consciousness provides value assignment to goals. Perhaps human consciousness includes (is?) our belief generator. Perhaps consciousness is a cognitive  and social contagious infection which the symptoms are persons. Who knows how to untangle a metaphorical web using just its metaphors?

We need beliefs to fictionalize an impersonal world, filing it with meaningful narratives, appropriate reasons and reasonable causes. We also need a world with persons. Other persons and ourselves. But an indifferent Universe does not offer anything like that, only pain and pleasure, life and death. So why not, collectively, make up everything else? 

"Hate Orgoreyn? No, how should I? How does one hate a country, or love one? Tibe talks about it; I lack the trick of it. I know people, I know towns, farms, hills and rivers and rocks, I know how the sun at sunset in autumn falls on the side of a certain plowland in the hills; but what is the sense of giving a boundary to all that, of giving it a name and ceasing to love where the name ceases to apply? What is love of one's country; is it hate of one's uncountry? Then it's not a good thing. Is it simply self-love? That's a good thing, but one mustn't make a virtue of it, or a profession... Insofar as I love life, I love the hills of the Domain of Estre, but that sort of love does not have a boundary-line of hate. And beyond that, I am ignorant, I hope." Ursula K. Le Guin, The Left Hand of Darkness

"There was kindness. I and certain others, an old man and one with a bad cough, were recognized as being least resistant to the cold, and each night we were at the center of the group, the entity of twenty-five, where it was warmest. We did not struggle for the warm place, we simply were in it each night. It is a terrible thing, this kindness that human beings do not lose. Terrible, because when we are finally naked in the dark and cold, it is all we have. We who are so rich, so full of strength, we end up with that small change. We have nothing else to give." Ursula K. Le Guin, The Left Hand of Darkness

"To oppose something is to maintain it. They say here "all roads lead to Mishnory." To be sure, if you turn your back on Mishnory and walk away from it, you are still on the Mishnory road. To oppose vulgarity is inevitably to be vulgar. You must go somewhere else; you must have another goal; then you walk a different road. Yegey in the Hall of the Thirty-Three today: "I unalterably oppose this blockade of grain-exports to Karhide, and the spirit of competition which motivates it." Right enough, but he will not get off the Mishnory road going that way. He must offer an alternative. [...] To be an atheist is to maintain God. His existence or his nonexistence, it amounts to much the same, on the plane of proof. Thus proof is a word not often used among the Handdarata, who have chosen not to treat God as a fact, subject either to proof or to belief: and they have broken the circle, and go free." Ursula K. Le Guin, The Left Hand of Darkness

Verniz

"He wanted his hearers to be frightened and angry. His themes were not pride and love at all, though he used the words perpetually; as he used them they meant self-praise and hate. He talked a great deal about Truth also, for he was, he said, "cutting down beneath the veneer of civilization." It is a durable, ubiquitous, specious metaphor, that one about veneer (or paint, or pliofilm, or whatever) hiding the nobler reality beneath. It can conceal a dozen fallacies at once. One of the most dangerous is the implication that civilization, being artificial, is unnatural: that it is the opposite of primitiveness... Of course there is no veneer, the process is one of growth, and primitiveness and civilization are degrees of the same thing. If civilization has an opposite, it is war. Of those two things, you have either one, or the other. Not both. It seemed to me as I listened to Tibe's dull fierce speeches that what he sought to do by fear and by persuasion was to force his people to change a choice they had made before their history began, the choice between those opposites." Ursula K. Le Guin, The Left Hand of Darkness

Percepção e Cultura

Os japoneses usam a palavra 'azul' descrever a luz verde dos semáforos. Esta particularidade deriva de, antes do período moderno, existir apenas uma palavra para os tons de azul e verde (ao). Por volta do século XI surgiu na literatura uma outra palavra para designar um tom esverdeado de azul (midori). Este tipo de conceito é comum também em português (e.g., escarlate é um tom de vermelho, mas não é normalmente considerado uma cor independente). Já no século XX, em parte por influencias culturais externas, midori foi promovida a cor, apesar de ainda restarem cicatrizes antigas como a designação da cor dos referidos semáforos. Esta falta de distinção ocorre noutras linguagens. Na Bíblia Hebraica ou na Odisseia de Homero, não existe palavra para azul. [1]

O mapa das cores é um espaço contínuo de tonalidades, e as cores são um sistema discreto de classificação. Existe sempre uma perda nesta discretização que, por sua vez, é cultural e historicamente contingente mas também dependente da forma como funcionam os nossos olhos e o nosso cérebro. Mas qual a influência da cultura? Brent Berlin and Paul Kay, nos anos 1960, procuraram regras universais que regiam como as culturas lidam com o espaço cromático. Eles descobriram que existem entre 2 e 11 nomes para as cores principais. E que quando existiam X cores, estas tendiam a ser as mesmas.

Segundo o diagrama, se uma cultura usa apenas duas cores, estas serão o branco e o preto (claro/escuro). Se uma cultura usa três cores, a terceira tendencialmente é o vermelho. E assim sucessivamente. Quando se chega à sexta cor é o momento em que o azul se separa do verde. Das 98 línguas estudadas, 92 seguiam este padrão.

E em português? É curioso como temos nomes para vários tons relacionados com vermelho (escarlate, laranja, púrpura, violeta, roxo, magenta) mas quase nada para o verde. No entanto, se olharmos para a seguinte foto dificilmente podemos afirmar que predomina uma única cor (verde) quando realmente há vários tons de verde e que apenas nos falta vocabulário para os nomear.

A cor é uma noção subjectiva, não existe 'lá fora', tendo apenas presença na imagem que o cérebro constrói para mapear o que o rodeia. O mesmo se passa com sons, sabores, a sensação de calor e outra informação recolhida pelos nossos vários sentidos. O vocabulário para cor, porém, ajuda-nos a processar de forma distinta uma parte do 'nosso' mundo, o umwelt (a selecção natural tende a eliminar os sentidos menos úteis em ralação à região habitada pela respectiva população). Um conjunto rico de palavras para cor permite uma maior qualidade da percepção, uma recolha mais fina da informação disponível. A foto acima seria mais rica se a língua portuguesa tivesse dez palavras distintas para verde. E a cor é apenas uma dimensão possível. Um botânico ou um jardineiro retirariam ainda mais detalhe da mesma foto. Àparte das nossas limitações cognitivas, uma cultura e uma língua mais ricas conceptualmente tornam a nossa visão do mundo numa experiência também ela mais rica.  

[1] http://www.empiricalzeal.com/2012/06/05/the-crayola-fication-of-the-world-how-we-gave-colors-names-and-it-messed-with-our-brains-part-i/ 

Tradições

Um ovo fertilizado não é uma pessoa. O adulto que resultou desse ovo é uma pessoa. O que aconteceu nesse intermédio? Existe um instante entre as duas anteriores afirmações em que se passou do estado de não-pessoa para pessoa? A resposta é simples: não. Procurar uma fronteira precisa neste assunto é uma missão equivocada. A noção de pessoa é gradual, não existe um conjunto suficiente e necessário de características objectivas que a determine. Resta-nos, assim, o consenso possível de uma definição. 

O consenso actual, nos países seculares, é firmado algures na segunda dezena de semanas de gravidez. Este é um período, antes da formação do sistema nervoso do feto, no qual é admissível a possibilidade de aborto. Deste modo, garante-se a prevenção da dor e a inexistência de um ser consciente (aliás, uma asserção ultra-conservadora para qualquer definição científica de consciência). Este prazo derivou do consenso possível entre especialistas de medicina, os profissionais com maior capacidade de se pronunciarem sobre o assunto.

A opinião católica, porém, funciona através de mecanismos de tradição, processos onde a razão presente e a evidência (contrária) têm pouco a dizer. Se existe uma política defendida pela Igreja sobre o assunto, é esta política que tem de ser promovida. É uma questão de autoridade e costume. Mas que tradição é essa? A Igreja nem sempre manteve a mesma opinião. Nos séculos entre Santo Agostinho e São Tomás de Aquino era considerado que o feto só recebia uma alma no momento em que se começasse a mover na barriga materna. Isto ocorre entre a 16ª e 22ª semana de gravidez (mais tarde que o limite para o aborto legal actual). Antes desse momento, o aborto não era considerado problemático.

As posições tomadas pela Igreja não foram indiferentes às discussões sobre a procriação. Para Aristóteles, o esperma («a semente do homem») era o princípio activo da geração humana, sendo que a mulher providenciava apenas a matéria passiva para a semente crescer. Muitos pensadores que seguiam esta explicação faziam a distinção entre vida formada e não-formada, aceitando que, à posteriori, a matéria não-formada seria animada por uma alma. Uma segunda teoria defendia que o esperma e o útero continham desde logo o pneuma, um elemento espiritual, que quando misturados produzia de imediato a alma do embrião. Esta explicação era defendida pelos Estóicos e por alguns cristãos. Uma terceira explicação, adoptada por Tertuliano, retirava o papel da mulher deste processo mas mantinha a tese da alma estar presente desde a concepção. Estas explicações filosóficas sobre a biologia da procriação influenciaram fortemente as discussões cristãs sobre o estatuto moral do embrião [1].

Em 1588, o Papa Sisto V defendeu a tese da alma existir a partir da concepção. Em 1591, apenas três anos depois, o Papa Gregório XIV revogou a bula anterior voltando à tese medieval da incorporação tardia da alma que só foi, por sua vez, revogada definitivamente em 1869, por Pio IX (na bula Apostolicae Sedis). A partir de Pio IX, juntando-se outras bulas na mesma direcção durante o Século XX, chegou-se à posição oficial e actual da Igreja [2]. Uma posição que, apesar de uma história mais antiga, tem 'apenas' 150 anos.

De qualquer forma, para a Igreja uma pessoa é alguém que detenha uma alma [3]. A tese corrente que a alma entra no momento da concepção, faz com que a Igreja equacione o aborto ao assassinato de uma pessoa. Assim, assumindo este pressuposto, é lógico que se pretenda impedir o aborto até a quem não é católico. Um assassino não deixa de o ser pelas crenças que defende. Seja ateu, seja religioso, se faz um aborto é responsável por um crime gravíssimo. O problema é que os católicos não se comportam desta forma, no seu dia-a-dia. Numa sociedade com uma tão grande taxa de crentes, perante tantos milhares de assassinatos de inocentes, o seu silêncio é ensurdecedor. Se o Estado financiasse o assassinato forçado de milhares de idosos por ano, esse seria um acto que a sociedade civil não suportaria. Porque não agem, então, os católicos? A minha explicação não é que um católico é indiferente ao assassinato de inocentes (uma afirmação ridícula, como é ridícula a afirmação que um ateu não possui juízo ético). A minha explicação é que o católico típico -- incluído a maioria da hierarquia da Igreja -- sabe, mesmo que inconscientemente, que um aborto nos prazos legais, de facto, não é o mesmo que assassinar uma pessoa. Um facto que se reflecte no comportamento dos crentes, apesar de toda a regulamentação eclesiástica em sentido contrário.

Mede-se melhor alguém, não pelas crenças que afirma ter, mas pelas acções que toma ou omite.

Refs:

[1] Smith - A Christian Response to the New Genetics (pp. 112-113)
[2] The History of Abortion in the Catholic Church, http://www.catholicsforchoice.org/pubs/cfc_archive/articles/TheHistoryofAbortion.asp
[3] Catecismo da Igreja Católica, Parte III.1.1.1

Passado, Presente, Futuro

"As an island in space, the world could not rely on imports from elsewhere; nevertheless, it was already heavily dependent upon imports from elsewhen. [...] The human species, through technological progress, had made itself more than ninety percent dependent on phantom carrying capacity – a term we must now define. Phantom carrying capacity means either the illusory or the extremely precarious capacity of an environment to support a given life form or a given way of living. It can be quantitatively expressed as that portion of a population that cannot be permanently supported when temporarily available resources become unavailable." Overshoot, William R. Catton

Lei de von Liebig

"[W]e need to step outside the usual economic or political frames of thought, go back two-thirds of a century before the 1929 crash, and reexamine for its profound human relevance a principle of agricultural chemistry formulated in 1863 by a German scientist, Justus von Liebig. That principle set forth with great clarity the concept of the “limiting factor” [...] Carrying capacity is limited not just by food supply, but potentially by any substance or circumstance that is indispensable but inadequate. The fundamental principle is this: whatever necessity is least abundantly available (relative to per capita requirements) sets an environment’s carrying capacity.

While there is no way to repeal this principle, which is known as “the law of the minimum,” or Liebig's law, there is a way to make its application less restrictive. People living in an environment where carrying capacity is limited by a shortage of one essential resource can develop exchange relationships with residents of another area that happens to be blessed with a surplus of that resource but happens to lack some other resource that is plentiful where the first one was scarce.

Trade does not repeal Liebig’s law. Only by knowing Liebig’s law, however, can we see clearly what trade does do, in ecological terms. Trade enlarges the scope of application of the law of the minimum. The composite carrying capacity of two or more areas with different resource configurations can be greater than the sum of their separate carrying capacities. ...] A good many of the events of human history need to be seen as efforts to implement the principle of scope enlargement." Overshoot, William R. Catton

Dilbert

Alguns cartoons do Dilbert relativos a questões estatísticas:

[via http://stats.stackexchange.com/questions/423/what-is-your-favorite-data-analysis-cartoon]

Overton

A janela de Overton é um conceito da ciência política, introduzido por Joseph P. Overton, que descreve um facto social inescapável: os conceitos considerados aceitáveis para serem discutidos publicamente são muito limitados. Esta janela altera-se com o tempo, reciclando, esquecendo, introduzindo termos e ideias, soluções. Por exemplo, no século XIX era possível falar publicamente de políticas raciais ou de eugenia, mas agora seria equivalente a um suicídio político (ao ponto do corrector automático não conhecer a palavra eugenia e sugerir-me 'Eugénia'). Como exemplo inverso temos o casamento homossexual, algo aceitável para discussão hoje em dia, mas mesmo o mais racional, coerente e influente dos pensadores liberais de há 100 anos jamais ousaria discutir o tema em público. Não é certo que a janela se alargue com os anos, mesmo imaginando possível uma qualquer métrica. A única certeza empírica é a janela ser limitada. 

O transformar da opinião pública para que certas ideias passem de impensáveis para radicais, de radicais para aceitáveis, e finalmente de aceitáveis para essenciais, é um papel social da maior importância. É um caminho percorrido por inúmeras pessoas ao longo dos séculos, desde filósofos e políticos a outros agentes sociais. Os direitos humanos, a igualdade das mulheres, a abolição, a separação da Igreja e do Estado, a liberdade de expressão, o trabalho infantil, a independência da Justiça, todos elas consideradas ideias impensáveis algures no passado. Devemos muito a todos os que lutaram e sofreram as consequências para nos legar estas subtis mas críticas heranças. 

A minha opinião é que existe um problema muitíssimo grave com a actual janela de Overton. A civilização globalizada caminha para uma mudança radical, talvez inédita, mas não é possível abordar certos tipos de solução por políticos e outras figuras públicas que prezem a sua reputação. Esta mudança deriva de estarmos a atingir uma série de limites físicos do nosso planeta. Limites energéticos, sobre-população, o colapso de um sistema financeiro de natureza exponencial, uma pressão intolerável sobre o ecossistema. O tema do ecossistema é abordável mas não o é um certo tipo de raciocínio que aponta à sua resolução. Não é admissível explicitar a ligação integral entre o ecossistema planetário e a economia global. Não é possível admitir que o crescimento -- actualmente um conceito sacralizado -- possa ser negativo à economia e à sociedade, que é possível pensar políticas baseadas na estabilização da produção global (a steady-state economics) e não no crescimento infinito. Igualmente, não pertence à janela de Overton o constatar que todas estas questões estão relacionadas, e que os problemas económicos do Ocidente podem ser meros sintomas iniciais dos limites que estão a ser atingidos. 

Um exemplo particularmente difícil: será inevitável discutir a limitação do número de carros privados existentes. Estes são responsáveis pela maior parte dos cerca de 80% do consumo de petróleo mundial que é dedicado aos transportes rodoviários. A médio prazo (talvez 10, talvez 20 anos) este consumo crescente colocará em perigo o uso do petróleo (de extracção barata) para uma actividade à qual não existe alternativa: a aviação. Mas que político arriscaria informar a população que será preciso mudar a forma de nos deslocarmos para acomodar uma diminuição progressiva e a eventual proibição do uso de automóveis daqui a uma geração? A resposta é simples: ninguém. Este é um tipo de discussão que está totalmente fora da janela de Overton. O perigo é que se, e quando, este assunto entrar na discussão pública, a maior parte do combustível barato disponível estará já demasiado perto da exaustão. A partir daí o combustível da aviação ficará dependente de fontes fósseis muito mais caras, o que implicará o colapso do mercado aéreo para níveis de décadas atrás, pelo preço que os bilhetes atingirão para acomodar o preço do combustível. Poderá isto não acontecer? É possível. É possível que ocorra algum desenvolvimento tecnológico -- que os últimos 50 anos de investimento das companhias petrolíferas foram incapazes de conseguir -- e nos inundem de algum novo tipo de petróleo economicamente competitivo*. Mas não é provável. E no entanto, a probabilidade deste evento ocorrer é, literalmente, indiscutível.

* O pico de produção de petróleo convencional ocorreu por volta de 2006. [World Energy Outlook 2010, Key Graphs, p.7]

• João Neto: Do you think math concepts exist independently of persons (aka, mathematical platonism)?
• Alexander Nikitin: Define 'exist'. --- 
• JN: Well, I overload the word 'exist' with two meanings: (i) existence independently of persons (let's call it exist-1) and, (ii) existence due to persons (exist-2). It's the separation of Maps and the Territory. 
• AN: You can argue that only mind exist. Everything else are just ideas in your mind. Then you have an idea of natural numbers in your head. And you have an idea of a set of axioms and deduction rules that define your space of natural numbers. Then you start doing different things with your natural numbers following the rules and you find that the space has a structure and properties that depend on those axioms and rules only and nothing else in your mind. Your mind can do whatever it wants. It can have any other ideas, feelings and states, but whenever it follows the axioms and rules it always gets the same results. Does that mean that there is something that exists independently of your mind? 
• JN:  But there is evidence against solipsism: we have lots of data from our senses and tech extensions. And my mind cannot do whatever it wants, especially when I'm driving :-) We are more than one human, why would one single mind be special? And if we assume two or more minds (a belief that literally every one follows) then how could we explain the coincidence of sense data? The belief that 'only mind exist' does not help us at all, it dissolves everything and give us nothing. 
• AN: If you believe that the 'real' world exists and math is just an artifact of human brain activity. Then notice several things: (1) You can define a mathematical system as purely abstract and symbolical without any attempts to model anything 'real'. You can even ask a computer to generate a random set of symbols, axioms and rules for you to exclude any 'subconscious' mapping to anything real; (2) You can give that math system to any other people and/or computers and notice that if they follow the rules they always get the same results regardless of the properties of their minds; (3) If you eventually manage to map your system to something 'real' you will notice another strange thing: the results of physical experiments will always follow predictions derived from the system once the mapping has been established, but it NEVER work in the opposite direction - physical results NEVER disprove any conclusions derived from the axioms and rules of the math system. They can prove that the mapping was wrong, but they can't 'bend' the 'truths' of the math system. As we see math is self-sufficient. Substrate independent. And physics always follows math. Then what is more 'real'? 
• JN: The first and second point also work for board games. And games can be formalized as math objects. However, defending that, say, Chess exist-0 is a very strange assertion for me. I don't see the relevance of the third point. Some math mappings are adequate to formalize scientific models (since there are infinite mathematical models, only a vanishing part of them are really useful). And, sure, enough counter-evidence can cancel the previous adequacy between model and data. So what? Why would we want to use data to bend Math? We just try to find or create another Math model that does the trick. They are tools just like anything else. We use many maps/models. We could imagine a spectrum from totally objective to totally subjective. Humans developed a discipline to deal with those at the objective extreme of that spectrum and called it Math (Physics, which is just another family of models, is a close neighbor). 
• AN: The third point is important because it tells us that math is not just a map. It has predictive power. A map doesn't give you more information than you already know from your 'real' data. It shows you only that part of the territory which you already have experienced. Once you get mathematical model you instantly know everything about your territory. All human engineering is based on this idea. Every day we build bridges, planes, skyscrapers - 'real' objects that never existed before - and we can do it successfully because we rely on the empirical fact that once we get the math right we can be sure that the 'real' system's behaviour will follow the math. Our experience tells us that the 'real' world is not random. It follows certain rules. That means that the rules exist. The rules are abstract concepts they are not a part of the physical world because they define it. So if you believe that the world is not random then you should accept that abstract concepts can exist independently of anything in the 'real' world. I asked you to define 'exist' in the beginning because abstract concepts don't exist in the same sense as 'real' things. We can not put them in any specific place and point in time. They exist outside of space-time. I think I was not clear from the beginning. My view is not just that abstract mathematical objects exist. My belief is that mathematics is the only thing that exists. Our 'real' world is just one of all possible mathematical systems that has 'self-aware' objects that precept their environment as 'real'. That's all. 
• JN: When you say that the fundamental basis is Math, the only thing that exists, and outside space-time, you are putting yourself into a position that cannot be settled by evidence. Which is not unreasonable since we are talking metaphysics. I recently already read similar arguments from people like Bill Taylor, Massimo Pigliucci or Steve Landsburg (all quite clever chaps). I think we cannot possible breach the abyss between the Territory and the Map (for me, we are entirely Map denizens). I just don't like positions which are 100% argument and 0% evidence. So, I try to minimize my own 100% argument beliefs: I don't assume anything from the Territory except that it generates events. And that's because we are able to measure those events (these are partial measures due to the limitations of our sense apparatus). These events, as you said, do have some regularities that we adapt ourselves to them by customs and culture, and formalize some into scientific laws. Why there are regularities? I don't know. Nobody knows (anyway, as far as we know people would be impossible in a more random universe). It's a bit like Hume's guillotine for ethics, there's an ontological guillotine between existence-0 and existence-1. I would bet that no one will ever cross it (in fact, from my position, that does not even make sense). Now, when you say: "Our experience tells us that the 'real' world is not random. It follows certain rules. That means that the rules exist." I think you are falling into Whitehead's Fallacy of Misplaced Concreteness (aka as ET Jayne's Mind Projection Fallacy). Rules imho only exist-1 in our minds. Perhaps using a less objective example, I can explain it better: humans share lots of cognitive bias. We can extract rules from well-made psychological studies. But we don't assume that these rules exist outside its scientific context. For me, the same happens with electrons, QM, etc. I see some wisdom in the "Shut Up and Calculate" attitude. In this case, we can only appreciate each other arguments. At the end of the day, we are confronting aesthetic positions not truly empirical ones.

Speech and Violence

The differences between speech and violence are not the differences between words and acts, or between good and evil.

Some speech promotes violence, like teaching xenophobia or religious intolerance. Some violence protects speech, like the lawful actions of the police in a free society. The line between speech and violence is too blurry, they overlap too much on each other. Why can't someone publicly deny historical or scientific facts? Why can't religious people verbally express their emotions against heresy? This is not about spreading false personal accusations (like defamation) or taking advantage of someone's name or work (like plagiarism or fraud). The argument is symmetric: there should be nothing wrong about denying or showing disrespect about beliefs or to argue how unfounded are certain system of ideas. For example, it is wrong for a society to apply violence or censorship to the ones exposing Homeopathy for what it is (a placebo) and it is also wrong for the same society to prohibit the expression of homeopathic ideas (which is not the same as allowing people to sell homeopathic products branded as medicine, which they are not, but that is a matter of fraud, not a matter of free-speech).

One role of the state is to protect its citizens. The state will always classify and restrict variants of violence and speech. In the category of 'violent speech' it is common to find notions like libel, slander, obscenity, hate speech, blasphemy, incitement. Each society adapts the broadness of this category, but we will not find a society that dismiss the idea entirely. And this is because speech can be violent and every feasible society always restricts violence one way or the other. 

The focus should be in the discourse's subject. Is it about people, communities, specific individuals, or is it about ideas, opinions, beliefs? People have rights, ideas do not. No one owns an idea, no person 'is' one. Every criticism over an idea should never be interpreted as violence against its believers, even if they see it that way. There’s no right to not be offended. On the other hand, a verbal and personal attack can be interpreted as a violent act, just like a punch. Only the latter, not the former, should concern the judicial system. This is the difference between blasphemy and hate speech, between mocking ideas and defaming communities. Religions are systems of ideas and rituals. A religion has followers but it is not them. The same goes with Ideologies or Corporations. All systems of belief should and must be open to criticism. Every free society that gives them protective status walks a messy and dangerous path. People are, by definition, worthy of respect. Beliefs must strive to be.

Modelos

What is a random variable? That’s easy. It’s a measurable function on a probability space. What’s a probability space? Easy too. It’s a measure space such that the measure of the entire space is 1. 

Probability theory avoids defining randomness by working with abstractions like random variables. This is actually a very sensible approach and not mere legerdemain. Mathematicians can prove theorems about probability and leave the interpretation of the results to others. 

As far as applications are concerned, it often doesn’t matter whether something is random in some metaphysical sense. The right question isn’t “is this system random?” but rather “is it useful to model this system as random?” Many systems that no one believes are random can still be profitably modeled as if they were random. 

Probability models are just another class of mathematical models. Modeling deterministic systems using random variables should be no more shocking than, for example, modeling discrete things as continuous. For example, cars come in discrete units, and they certainly are not fluids. But sometimes it’s useful to model the flow of traffic as if it were a fluid. (And sometimes it’s not.) 

Random phenomena are studied using computer simulations. And these simulations rely on random number generators, deterministic programs whose output is considered random for practical purposes. This bothers some people who would prefer a “true” source of randomness. Such concerns are usually misplaced. In most cases, replacing a random number generator with some physical source of randomness would not make a detectable difference. The output of the random number generator might even be higher quality since the measurement of the physical source could introduce a bias. John D. Cook 

Mapas

"The central dogma of statistics is that data should be viewed as realizations of random variables. This has been a very fruitful idea, but it has its limits. It’s a reification of the world. And like all reifications, it eventually becomes invisible to those who rely on it." John D. Cook

"Statisticians can get awfully uptight about numerical approximations. They’ll wring their hands over a numerical routine that’s only good to five or six significant figures but not even blush when they approximate some quantity by averaging a few hundred random samples. Or they’ll make a dozen gross simplifications in modeling and then squint over whether a p-value is 0.04 or 0.06. The problem is not accuracy but familiarity. We all like to draw a circle around our approximation of reality and distrust anything outside that circle. After a while we forget that our approximations are even approximations." John D. Cook

"A well-made language is no indifferent thing; not to go beyond physics, the unknown man who invented the word heat devoted many generations to error. Heat has been treated as a substance, simply because it was designated by a substantive, and it has been thought indestructible". The Foundations of Science, Henri Poincaré