Posts com Tag ‘descartes’

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more about “Light Fantastic – BBC CH4“, posted with vodpod

Parte 2 – Light of Reason

Parte 3 – The Stuff of Light

Parte 4 – Light, Universe and Everything

Meditações na  Filosofia Primeira. 

 

Veja também: 

Meditações Metafísicas

The Epistemological Foundation – Descartes’ God

Absolute Certainty and the Cartesian Circle

Recall that in the First Meditation Descartes supposed that an evil demon was deceiving him. So as long as this supposition remains in place, there is no hope of gaining any absolutely certain knowledge. But he was able to demonstrate God’s existence from intuitively grasped premises, thereby providing, a glimmer of hope of extricating himself from the evil demon scenario. The next step is to demonstrate that God cannot be a deceiver. At the beginning of the Fourth Meditation, Descartes claims that the will to deceive is “undoubtedly evidence of malice or weakness” so as to be an imperfection. But, since God has all perfections and no imperfections, it follows that God cannot be a deceiver. For to conceive of God with the will to deceive would be to conceive him to be both having no imperfections and having one imperfection, which is impossible; it would be like trying to conceive of a mountain without a valley. This conclusion, in addition to God’s existence, provides the absolutely certain foundation Descartes was seeking from the outset of the Meditations. It is absolutely certain because both conclusions (namely that God exists and that God cannot be a deceiver) have themselves been demonstrated from immediately grasped and absolutely certain intuitive truths.

This means that God cannot be the cause of human error, since he did not create humans with a faculty for generating them, nor could God create some being, like an evil demon, who is bent on deception. Rather, humans are the cause of their own errors when they do not use their faculty of judgment correctly. Second, God’s non-deceiving nature also serves to guarantee the truth of all clear and distinct ideas. So God would be a deceiver, if there were a clear and distinct idea that was false, since the mind cannot help but believe them to be true. Hence, clear and distinct ideas must be true on pain of contradiction. This also implies that knowledge of God’s existence is required for having any absolutely certain knowledge. Accordingly, atheists, who are ignorant of God’s existence, cannot have absolutely certain knowledge of any kind, including scientific knowledge.

But this veridical guarantee gives rise to a serious problem within the Meditations, stemming from the claim that all clear and distinct ideas are ultimately guaranteed by God’s existence, which is not established until the Third Meditation. This means that those truths reached in the Second Meditation, such as “I exist” and “I am a thinking thing,” and those principles used in the Third Meditation to conclude that God exists, are not clearly and distinctly understood, and so they cannot be absolutely certain. Hence, since the premises of the argument for God’s existence are not absolutely certain, the conclusion that God exists cannot be certain either. This is what is known as the “Cartesian Circle,” because Descartes’ reasoning seems to go in a circle in that he needs God’s existence for the absolute certainty of the earlier truths and yet he needs the absolute certainty of these earlier truths to demonstrate God’s existence with absolute certainty.

Descartes’ response to this concern is found in the Second Replies. There he argues that God’s veridical guarantee only pertains to the recollection of arguments and not the immediate awaRenéss of an argument’s clarity and distinctness currently under consideration. Hence, those truths reached before the demonstration of God’s existence are clear and distinct when they are being attended to but cannot be relied upon as absolutely certain when those arguments are recalled later on. But once God’s existence has been demonstrated, the recollection of the clear and distinct perception of the premises is sufficient for absolutely certain and, therefore, perfect knowledge of its conclusion (see also the Fifth Meditation at AT VII 69-70: CSM II XXX). 

In: Internet Encyclopedia of Phylosophy

Self-organization is a process of attraction and repulsion in which the internal organization of a system, normally an open system, increases in complexity without being guided or managed by an outside source. Self-organizing systems typically (though not always) display emergent properties.

Contents

 

Overview

The most robust and unambiguous examples of self-organizing systems are from physics. Self-organization is also relevant in chemistry, where it has often been taken as being synonymous with self-assembly. The concept of self-organization is central to the description of biological systems, from the subcellular to the ecosystem level. There are also cited examples of “self-organizing” behaviour found in the literature of many other disciplines, both in the natural sciences and the social sciences such aseconomics or anthropology. Self-organization has also been observed in mathematical systems such as cellular automata.

Sometimes the notion of self-organization is conflated with that of the related concept of emergence. Properly defined, however, there may be instances of self-organization without emergence and emergence without self-organization, and it is clear from the literature that the phenomena are not the same. The link between emergence and self-organization remains an active research question.

Self-organization usually relies on four basic ingredients:

  1. Positive feedback
  2. Negative feedback
  3. Balance of exploitation and exploration
  4. Multiple interactions

History of the idea

The idea that the dynamics of a system can tend by themselves to increase the inherent order of a system has a long history. One of the earliest statements of this idea was by the philosopher Descartes, in the fifth part of his Discourse on Method, where he presents it hypothetically.[citation needed] Descartes further elaborated on the idea at great length in his unpublished work The World.

The ancient atomists (among others) believed that a designing intelligence was unnecessary, arguing that given enough time and space and matter, organization was ultimately inevitable, although there would be no preferred tendency for this to happen. What Descartes introduced was the idea that the ordinary laws of nature tend to produce organization[citation needed] (For related history, see Aram Vartanian, Diderot and Descartes).

Beginning with the 18th century naturalists a movement arose that sought to understand the “universal laws of form” in order to explain the observed forms of living organisms. Because of its association with Lamarckism, their ideas fell into disrepute until the early 20th century, when pioneers such as D’Arcy Wentworth Thompson revived them. The modern understanding is that there are indeed universal laws (arising from fundamental physics and chemistry) that govern growth and form in biological systems.

Originally, the term “self-organizing” was used by Immanuel Kant in his Critique of Judgment, where he argued that teleology is a meaningful concept only if there exists such an entity whose parts or “organs” are simultaneously ends and means. Such a system of organs must be able to behave as if it has a mind of its own, that is, it is capable of governing itself.

In such a natural product as this every part is thought as owing its presence to the agency of all the remaining parts, and also as existing for the sake of the others and of the whole, that is as an instrument, or organ… The part must be an organ producing the other parts—each, consequently, reciprocally producing the others… Only under these conditions and upon these terms can such a product be an organized and self-organized being, and, as such, be called a physical end.

The term “self-organizing” was introduced to contemporary science in 1947 by the psychiatrist and engineer W. Ross Ashby. It was taken up by the cyberneticians Heinz von FoersterGordon PaskStafford Beer and Norbert Wiener himself in the second edition of his “Cybernetics: or Control and Communication in the Animal and the Machine” (MIT Press 1961).

Self-organization as a word and concept was used by those associated with general systems theory in the 1960s, but did not become commonplace in the scientific literature until its adoption by physicists and researchers in the field of complex systems in the 1970s and 1980s.[1] After 1977’s Ilya Prigogine Nobel Prize, the thermodynamic concept of self-organization received some attention of the public, and scientific researchers start to migrate from the cibernetic view to the thermodynamic view.

Examples

The following list summarizes and classifies the instances of self-organization found in different disciplines. As the list grows, it becomes increasingly difficult to determine whether these phenomena are all fundamentally the same process, or the same label applied to several different processes. Self-organization, despite its intuitive simplicity as a concept, has proven notoriously difficult to define and pin down formally or mathematically, and it is entirely possible that any precise definition might not include all the phenomena to which the label has been applied.

It should also be noted that, the farther a phenomenon is removed from physics, the more controversial the idea of self-organization as understood by physicists becomes. Also, even when self-organization is clearly present, attempts at explaining it through physics or statistics are usually criticized as reductionistic.

Similarly, when ideas about self-organization originate in, say, biology or social science, the farther one tries to take the concept into chemistry, physics or mathematics, the more resistance is encountered, usually on the grounds that it implies direction in fundamental physical processes. However the tendency of hot bodies to get cold (see Thermodynamics) and by Le Chatelier’s Principle– the statistical mechanics extension of Newton’s Third Law– to oppose this tendency should be noted.

Self-organization in physics

There are several broad classes of physical processes that can be described as self-organization. Such examples from physics include:

  • self-organizing dynamical systems: complex systems made up of small, simple units connected to each other usually exhibit self-organization
  • In spin foam system and loop quantum gravity that was proposed by Lee Smolin. The main idea is that the evolution of space in time should be robust in general. Any fine-tuning of cosmological parameters weaken the independency of the fundamental theory. Philosophically, it can be assumed that in the early time, there has not been any agent to tune the cosmological parameters. Smolin and his colleagues in a series of works show that, based on the loop quantization of spacetime, in the very early time, a simple evolutionary model (similar to the sand pile model) behaves as a power law distribution on both the size and area of avalanche.
    • Although, this model, which is restricted only on the frozen spin networks, exhibits a non-stationary expansion of the universe. However, it is the first serious attempt toward the final ambitious goal of determining the cosmic expansion and inflation based on a self-organized criticality theory in which the parameters are not tuned, but instead are determined from within the complex system.[2]

Self-organization vs. entropy

Statistical mechanics informs us that large scale phenomena can be viewed as a large system of small interacting particles, whose processes are assumed consistent with well established mechanical laws such as entropy, i.e., equilibrium thermodynamics. However, “… following the macroscopic point of view the same physical media can be thought of as continua whose properties of evolution are given by phenomenological laws between directly measurable quantities on our scale, such as, for example, the pressure, the temperature, or the concentrations of the different components of the media. The macroscopic perspective is of interest because of its greater simplicity of formalism and because it is often the only view practicable.” Against this background, Glansdorff and Ilya Prigogine introduced a deeper view at the microscopic level, where “… the principles of thermodynamics explicitly make apparent the concept of irreversibility and along with it the concept of dissipation and temporal orientation which were ignored by classical (or quantum) dynamics, where the time appears as a simple parameter and the trajectories are entirely reversible.”[3]

As a result, processes considered part of thermodynamically open systems, such as biological processes that are constantly receiving, transforming and dissipating chemical energy (and even the earth itself which is constantly receiving and dissipating solar energy), can and do exhibit properties of self organization far from thermodynamic equilibrium.

LASER (acronym for “light amplification by stimulated emission of radiation”) can also be characterized as a self organized system to the extent that normal states of thermal equilibrium characterized by electromagnetic energy absorption are stimulated out of equilibrium in a reverse of the absorption process. “If the matter can be forced out of thermal equilibrium to a sufficient degree, so that the upper state has a higher population than the lower state (population inversion), then more stimulated emission than absorption occurs, leading to coherent growth (amplification or gain) of the electromagnetic wave at the transition frequency.”[4]

 

Self-organization in human society

The self-organizing behaviour of social animals and the self-organization of simple mathematical structures both suggest that self-organization should be expected in human society. Tell-tale signs of self-organization are usually statistical properties shared with self-organizing physical systems (see Zipf’s lawpower lawPareto principle). Examples such as Critical Massherd behaviourgroupthink and others, abound in sociologyeconomicsbehavioral finance and anthropology.[19]

In social theory the concept of self-referentiality has been introduced as a sociological application of self-organization theory by Niklas Luhmann (1984). For Luhmann the elements of a social system are self-producing communications, i.e. a communication produces further communications and hence a social system can reproduce itself as long as there is dynamic communication. For Luhmann human beings are sensors in the environment of the system. Luhmann put forward a functional theory of society.[citation needed]

Self-organization in human and computer networks can give rise to a decentralized, distributed, self-healing system, protecting the security of the actors in the network by limiting the scope of knowledge of the entire system held by each individual actor. TheUnderground Railroad is a good example of this sort of network.[original research?] The networks that arise from drug trafficking exhibit similar self-organizing properties.[original research?] Parallel examples exist in the world of privacy-preserving computer networks such as Tor.[original research?] In each case, the network as a whole exhibits distinctive synergistic behavior through the combination of the behaviors of individual actors in the network. Usually the growth of such networks is fueled by an ideology or sociological force that is adhered to or shared by all participants in the network.[original research?][citation needed]

In economics

In economics, a market economy is sometimes said to be self-organizing. Friedrich Hayek coined the term catallaxy to describe a “self-organizing system of voluntary co-operation,” in regard to capitalism. Most modern economists hold that imposing central planning usually makes the self-organized economic system less efficient. By contrast, some socialist economists consider that market failures are so significant that self-organization produces bad results and that the state should direct production and pricing. Many economists adopt an intermediate position and recommend a mixture of market economy and command economy characteristics (sometimes called a mixed economy). When applied to economics, the concept of self-organization can quickly become ideologically-imbued (as explained in chapter 5 of A. Marshall, The Unity of Nature, Imperial College Press, 2002).

In collective intelligence

Non-thermodynamic concepts of entropy and self-organization have been explored by many theorists. Cliff Joslyn and colleagues and their so-called “global brain” projects. Marvin Minsky‘s “Society of Mind” and the no-central editor in charge policy of the open sourced internet encyclopedia, called Wikipedia, are examples of applications of these principles – see collective intelligence.

Donella Meadows, who codified twelve leverage points that a self-organizing system could exploit to organize itself, was one of a school of theorists who saw human creativity as part of a general process of adapting human lifeways to the planet and taking humans out of conflict with natural processes. See Gaia philosophydeep ecologyecology movement and Green movement for similar self-organizing ideals. (The connections between self-organisation and Gaia theory and the environmental movement are explored in A. Marshall, 2002, The Unity of Nature, Imperial College Press: London).

Origem: Wikipédia, a enciclopédia livre.

Meditações metafísicas, ou, em outras traduções, Meditações sobre a filosofia primeira, que tem como subtítulo nas quais são demonstradas a existência de Deus e a distinção real entre a mente e o corpo, é o nome da obra de René Descartes escrita e publicada pelo autor pela primeira vez em 1641. Nesta obra encontra-se o mesmo sistema filosófico cartesiano introduzido no Discurso do Método.

O livro é composto por seis meditações, nas quais Descartes põe em dúvida toda crença que não seja absolutamente certa, real, factível, e a partir daí procura estabelecer o que é possível saber com segurança.

Na primeira meditação encontram-se quatro situações que podem confundir suficientemente a percepção, a ponto de invalidarem, seguramente, uma série de enunciados sobre o conhecimento. O principal destes quatro argumentos é o do gênio maligno que tem a capacidade de confundir a percepção e plantar dúvidas sobre tudo o que podemos conhecer acerca do mundo e suas propriedades. Porém, mesmo podendo falsear a percepção, não pode falsear a crença nas percepções – ou seja, ele pode contra-argumentar contra a percepção mas não contra a crença que incide sobre as percepções. Descartes também conclui que o poder de pensar e existir não podem ser corrompidos pelo gênio maligno.

Na Segunda Meditação encontra-se o argumento de Descartes acerca da certeza da própria existência, certeza que prevalece sobre qualquer dúvida:

Convenci-me de que não existe nada no mundo, nem céu, nem terra, nem mente, nem corpo. Isto implica em que também eu não exista? Não: se existe algo de que eu esteja realmente convencido é de minha própria existência. Mas existe um engandor de poder e astúcia supremos, que está deliberada e constantemente me confundindo. Neste caso, e mesmo que o enganador me confunda, sem dúvida eu também devo existir… a proposição “eu sou”, “eu existo”, deve ser necessariamente verdadeira para que eu possa expressá-la, ou para que algo confunda minha mente.

Em outras palavras, a consciência implica na existência. Em uma das réplicas às objeções que faz no livro, Descartes resumiu a passagem acima em sua hoje famosa sentença: penso, logo, existo (em latimcogito, ergo sum)

O restante do livro, que não difere muito do precedente Discurso do Método, sendo porém mais acessível, contém vários argumentos que os filósofos modernos consideraram menos convincentes, tais como os argumentos ontológicos para a existência de Deus e a suposta prova do dualismo entre mente e corpo.

Veja também

Origem: Wikipédia, a enciclopédia livre.

Também chamada de “ciência espiritual” , a antroposofia (“conhecimento do ser humano”) é uma filosofia que foi erigida por Rudolf Steiner. Ele a apresenta como um caminho para se colocar em busca da verdade que preenche o abismo historicamente criado desde a escolástica entre fé e ciência. Na visão de Steiner a realidade surge no encontro dos mundos da idéia e da percepção.

Steiner coloca que, ao se pensar o pensar começamos a acessar uma consciência diferente da cotidiana. A primeira experiência que podemos ter de um conceito que não encontra correspondente nas percepções do mundo é a vivência do próprio eu. É a primeira instância de uma experiência no puro pensar. A partir daí muito mais pode ser vivenciado no puro pensar, vários conceitos que não encontram correspondentes em percepções físicas, mas para isso Steiner diz ser necessário ampliar nossa a capacidade de nossa consciência e apresenta exercícios para tal.

A base epistemológica da antroposofia está contida na obra A filosofia da liberdade, assim como em sua tese de doutoramento, Verdade e ciência. Estes e vários outros livros de Steiner anteciparam a gradual superação do idealismo cartesiano e do subjetivismo kantiano da filosofia do século XX. Assim como Edmund Husserl e Ortega y Gasset, Steiner foi profundamente influenciado pelos trabalhos de Franz Brentano, e havia lido Wilhelm Dilthey em detalhe. Por meio de seus primeiros livros, de cunho epistemológico e filosófico, Steiner tornou-se um dos primeiros filósofos europeus a superar a ruptura entre sujeito e objeto que Descartes, a física clássica, e várias forças históricas complexas gravaram na mente humana ao longo de vários séculos.

Steiner definiu a antroposofia como “um caminho de conhecimento para guiar o espiritual do ser humano ao espiritual do universo.” O objetivo do antropósofo é tornar-se “mais humano”, ao aumentar sua consciência e deliberar sobre seus pensamentos e ações; ou seja, tornar-se um ser “espiritualmente livre”.

Steiner ministrou vários ciclos de palestras para médicos, a partir dos quais surgiu um movimento de medicina antroposófica que se espalhou pelo mundo e agora inclui milhares de médicos, psicólogos e terapeutas, e que possui seus próprios hospitais e universidades médicas. Outras vertentes práticas da antroposofia incluem: a arquitetura (Goetheanum), aagricultura biodinâmica, a educação infantil e juvenil (pedagogia Waldorf), a farmácia homeopática (Wala, Weleda, Sirimim), a filosofia (A “Filosofia da Liberdade”), a euritmia (“o movimento como verbo visível e som visível”), e os centros para ajuda de crianças especiais (Vilas Camphill).

A antroposofia possui seus detratores. Os críticos designaram-na como um culto com similaridades em relação aos movimentos da Nova Era. Se for um culto, contudo, é um que fortemente enfatiza a liberdade individual. Ainda, alguns críticos sustentam que os antropósofos tendem a elevar as opiniões pessoais de Steiner, muitas das quais são estranhas às visões das religiões ortodoxas, da ciência e das humanidades, ao nível das verdades absolutas. Se existe alguma verdade nesta crítica, a maior parte da culpa pertence não a Steiner, mas a seus estudantes. Steiner freqüentemente estimulou seus estudantes a testarem tudo o que ele dizia, e em muitas ocasiões, até mesmo implorou a eles que não tomassem nada do que dissesse com base na fé ou autoridade.

Outra crítica afirma que alguns antropósofos parecem distanciar suas atividades públicas da possível inferência de que a antroposofia é baseada sobre elementos esotéricos religiosos, tendendo a apresentá-los ao público como uma filosofia acadêmica não-sectária. Uma dificuldade em avaliar essa crítica é que ela contém um preconceito oculto porque ignora uma questão que a antroposofia procurou levantar e responder: é possível para aquele que pensa ser tanto cientificamente quanto espiritualmente cognitivo, ao mesmo tempo? A antroposofia afirma que isso é possível. A crítica supramencionada, por outro lado, assume que não é possível, e portanto encontra uma contradição entre a afirmação de um não-sectarismo e um embasamento na experiência supra-sensível.