janeiro 27, 2011

Umwelt

"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? [...] a blind person does not miss vision. They do not conceive of it. Electromagnetic radiation is simply not part of their umwelt.

The more science taps into these hidden channels, the more it becomes clear that our brains are tuned to detect a shockingly small fraction of the surrounding reality. Our sensorium is enough to get by in our ecosystem, but is does not approximate the larger picture." David Eagleman [link]

janeiro 24, 2011

Fronteiras

A xenofobia faz para uma comunidade o que a membrana faz à célula e as sinfonias de feromonas ao formigueiro. Elas definem a fronteira, são função de separação e controlo, de homeostase. Mas querem as comunidades ser comparadas com células e insectos?

janeiro 20, 2011

Adaptação

"When I was a child, I used to pray to God for a bicycle. But then I realized that God doesn't work in that way—so I stole a bike and prayed for forgiveness!" Emo Philips

janeiro 17, 2011

Ficções

"Many anthropologists have observed that when they ask their native informants about «theological» details—their gods' whereabouts, specific history, and methods of acting in the world— their informants find the whole inquiry puzzling. Why should they be expected to know or care anything about that? Given this widely reported reaction, we should not dismiss the corrosive hypothesis that many of the truly exotic and arguably incoherent doctrines that have been unearthed by anthropologists over the years are artifacts of inquiry, not pre-existing creeds. It is possible that persistent questioning by anthropologists has composed a sort of innocently collaborative fiction, newly minted and crystallized dogmas generated when questioner and informant talk past each other until a mutually agreed-upon story results. The informants deeply believe in their gods—"Everybody knows they exist!"—but they may never before have thought about these details (maybe nobody in the culture has!), which would explain why their convictions are vague and indeterminate. Obliged to elaborate, they elaborate, taking their cues from the questions posed." Daniel Dennett, Breaking the Spell.

janeiro 14, 2011

Gestão danosa

Quando se sabe muito pouco sobre o mundo, não é melhor criar e cultivar um modelo que tudo explica? E se este compensa para quem o aprende e para quem nele apostou o seu estatuto social, há medida que se cristaliza na cultura, na arte, na relação das pessoas, então o seu peso tende a esmagar as sementes de outras explicações. É admirável que a civilização europeia tenha rompido a inércia religiosa de séculos mas, em parte, é da responsabilidade dos seus representantes, pelos excessos deles próprios que não foram capazes de controlar.

janeiro 06, 2011

Initio

Quando se discute o relativo ou absoluto da ética, creio que usamos as pessoas como experiência e medida mas não o humano, que também somos, como base. Numa tábua rasa qualquer possibilidade ética coerente parece admissível. Mas a humanidade carrega um passado como espécie e os muitos compromissos das suas culturas. Está-nos inscrito um conjunto de restrições físicas e uma herança genética que limita a gama dos nossos comportamentos (de outra forma, não existiria a psicologia). Os seres humanos não são tábuas rasas. É esse diferente de zero que permite, por exemplo, a amamentação, o aprender da linguagem, o fundar da mente no que nos rodeia, criar um eu neste cérebro inchado de primata. E nessa gama do possível, um número ilimitado de personalidades, culturas, crenças e línguas. Porque não assumir algo similar para a ética? O diferente de zero é um ponto de partida para o que aceitamos e recusamos, para o que atrai e enoja. isto não significa ser o instinto um ideal - longe disso - mas uma força que é necessário reconhecer, algo que partilhamos como espécie e que não podemos esquecer nos argumentos filosóficos, legais ou científicos que tratam como podemos e devemos agir.

janeiro 04, 2011

Ontologia

"[...] in our view, the existence of a real world that was not created in our imagination, and which continues to go about its business according to its own laws, independently of what humans think or do, is the primary experimental fact of all, without which there would be no point to physics or any other science. The whole purpose of science is learn what that reality is and what its laws are. [...] Any theory about reality can have no consequences testable by us unless it can also describe what humans can see and know. For example, special relativity theory implies that it is fundamentally impossible for us to have knowledge of any event that lies outside our past light cone. Although our ultimate goal is ontological, the process of achieving that goal necessarily involves the acquisition and processing of human information. This information processing aspect of science has not, in our view, been sufficiently stressed by scientists. [...] We suggest that the proper tool for incorporating human information into science is simply probability theory and not the currently taught "random variable" kind, but the original llogical inference" kind of James Bernoulli and Laplace. For historical reasons [...] this is often called "Bayesian inference". When supplemented by the notion of information entropy, this becomes a mathematical tool for scientific reasoning of such power and versatility that we think it will require Centuries to explore all its capabilities." E.T. Jaynes, Probability in Quantum Theory (1996)