Osvaldo Pessoa - Profile on Academia.edu (original) (raw)
Conference Presentations by Osvaldo Pessoa
This is a study of types of causative present events in a molecular motor, which are proteins - s... more This is a study of types of causative present events in a molecular motor, which are proteins - such as myosin, kinesina and dynein - present inside the cells and associated with, among other functions, the transport of substances along microtubules rails ( Spudich, 2006). Molecular motors are essential for the whole body movement and play an important role in brain. It is known that their malfunction is associated with Alzheimer's disease (Stokin & Goldstein, 2006), and it is reasonable to assume that they are at the base of the deliberative processes of decision making.
Adopt a general perspective that can be characterized as a "methodological reductionism", to try to reduce the macroscopic causality recognized in biology the most basic causal events. A causal event is defined by the possibility of an intervention or manipulation. In a previous study, we identified three types of causal events in quantum systems (less than 0.1 nm) interacting with macroscopic measuring devices (Person, 2013).
In this study, we set aside the quantum scale and up to three orders of magnitude study the causal processes in macromolecules 50nm, immersed in an aqueous solution of the cell medium and described by classical physical chemistry. On this scale, the molecules receive the shock of a huge number of water molecules per second, which makes them around, rotating, vibrating and twisting stochastically in Brownian motion, with power of 10-8 watts order. The macromolecule relates to microtubule (in the case of kinesina and dynein) by means of two "feet", and detaches when one occurs hydrolysis of ATP molecule, a process whose full power for a macromolecule is only 10-16 watts. Even with extremely low power to the Brownian motion, the hydrolysis of ATP is essential for unidirectional movement of the protein. The molecular motor floating end along the microtubule towards the core or the core in the opposite direction. On average, however, dynein has a net shift towards the core (electrically more negative) and kinesina in the opposite direction (more positive charge). Understanding the mechanism involved is the result of research of the past 25 years, and will be presented briefly (Astumian, 2010).
Identify at least four types of causal events are present at the molecular motor movement.
(1) The Brownian motion of the macromolecule can be reduced to a set of individual collisions with water molecules, which provides power to the molecule explore the area available to it, the viscous medium. This is random mechanical causes.
(2) The molecular motor is attached to the microtubule by electrostatic attraction, with a key-lock type fitting. Such a fitting can be regarded as a causal event. If one foot is loose, it stochastically explore all its accessible region can be fixed in microtubule tens of nanometers more forward.
(3) To be able action molecular engine, it is essential frequent conversion of ATP molecule present in the aqueous solution to ADP + P, a hydrolysis process which occurs stochastically. In this chemical reaction, the release of a quantum of energy occurs, which leads to a change in the conformation of the protein molecules and release of a foot.
(4) To explain the existence of molecular motors and the efficient exercise of its biological function of transport and movement, one must take into account root causes associated with natural selection. There is actually a whole family of evolutionary lineages of molecular motors.
Books by Osvaldo Pessoa
A presente obra é marcada por um estilo de reflexão temática, que ressalta a preocupação dos auto... more A presente obra é marcada por um estilo de reflexão temática, que ressalta a preocupação dos autores com os rumos do avanço exponencial da tecnologia na vida humana. Essa preocupação está aqui delimitada aos estudos nas áreas de Filosofia da Mente, Ciência Cognitiva, Semiótica e Filosofia da Informação. Alguns dos pesquisadores dessas áreas têm verificado, com surpresa, recentes aplicações de teorias, hipóteses e conceitos desenvolvidos durante anos de pesquisa na elaboração de projetos que parecem escapar do controle de seus idealizadores. Exemplos dessa experiência surpreendente podem ser constatados nas recentes aplicações de pesquisas da Inteligência Artificial e da Ciência Cognitiva no projeto transhumanista, que visa a realização de um suposto aprimoramento da condição humana, Filosofia da Mente, Ciência Cognitiva e o pós-humano para onde vamos através de recursos da computação inteligente, da bioquímica, da nanotecnologia e da genética. No campo político e ético constatam-se aplicações bélicas, altamente polêmicas, por exemplo, como a aeronave autônoma de bombardeio Taranis.
Papers by Osvaldo Pessoa
TECCOGS : Revista Digital de Tecnologias Cognitivas, Dec 15, 2023
Resumo: Uma exposição didática sobre a física quântica abre o artigo, salientando-se a diferença ... more Resumo: Uma exposição didática sobre a física quântica abre o artigo, salientando-se a diferença entre a parte objetiva da teoria e sua parte interpretativa. Adota-se uma "interpretação ondulatória realista com colapsos" para expor cinco princípios básicos da teoria. Aborda-se então a questão de qual é o impacto da física quântica sobre a sociedade. Discorre-se sobre seu grande impacto científico e tecnológico, e em seguida examina-se com mais atenção o seu impacto teórico, em termos ontológico e epistemológico. Argumenta-se que impacto ontológico em nossa vida cotidiana se limita às aplicações tecnológicas, e que possíveis consequências filosóficas do princípio de incerteza e do indeterminismo não são importantes, e muito menos as consequências imaginadas pelo Misticismo Quântico com relação ao emaranhamento. Dentre as lições epistemológicas está que conhecemos a interpretação que mais se aproxima da verdade, mas não sabemos qual é ela, dentre as dezenas de interpretações propostas. Por fim, discutimos a tese de Forman, que envolve a questão de se a ciência é objetiva ou se é uma construção sócio-culturalmente negociada, como defende o relativismo. Concluímos por um "relativismo relativo": as interpretações podem ser fortemente influenciadas pela cultura, mas em uma ciência saudável a sua parte objetiva consegue se isolar das vicissitudes sociais e das intenções emotivas dos cientistas. Por fim, são dados alguns exemplos de influência da cultura, e de outros fatores, sobre as interpretações da Teoria Quântica.
Uma defesa cautelosa do ceticismo científico
Emergence of Autonomy in Contemporary Artificial Agents: Any Novelty?
Cybernetics and Human Knowing, 2008
ABSTRACT The article by Arnellos, Spyrou and Darzentas discusses the question of whether an artif... more ABSTRACT The article by Arnellos, Spyrou and Darzentas discusses the question of whether an artificial system, such as a robot or artificial life, can be made genuinely autonomous. The negative answer that they present is sound, but seems to us to be a simple consequence of the definitions adopted. We argue that the theoretical considerations presented, based on the notions of functional emergence and meaning, need further explanation in order to give support for their argument. As it is presented so far, not very much novelty is added to the already existent research on autonomous and cognitive robotics and artificial life. Also, we would like to challenge the defenders of the 'theory of self-referential systems' to set up conditions in which the theory would be considered falsified. The problem of whether life and autonomy could in principle be sustained with components other than carbon-
Entrevista com Osvaldo Pessoa Junior
Quando a abordagem histórica deve ser usada no ensino de ciências
Ciência & Ensino (ISSN 1980-8631), Sep 14, 2006
Measurement in Quantum Physics: Experimental and Formal Approaches
PhDT, 1990
ABSTRACT
Causal Models in the History of Science
Croatian Journal of Philosophy, Jul 1, 2005
The investigation of a method for postulating counterfactual histories of science has led to the ... more The investigation of a method for postulating counterfactual histories of science has led to the development of a theory of science based on general units of knowledge, which are called "advances". Advances are passed on from scientist to scientist, and may be seen as "causing" the appearance of other advances. This results in networks which may be analyzed in terms of probabilistic causal models, which are readily encodable in computer language. The probability for a set of advances to give rise to another advance is taken to be invariant through history, but depends on a typical time span which is an inverse function of the degree of development of science. Examples are given from the early science of magnetism and from the 19 t h century physics.
The Causal Strength of Scientific Advances
Boston studies in the philosophy of science, 2011
ABSTRACT This paper starts by presenting an overview of an approach to the theory of science base... more ABSTRACT This paper starts by presenting an overview of an approach to the theory of science based on units of scientific knowledge, named “advances”, connected by probabilistic causal relations. The notion of the “causal strength” of an advance is then introduced, and examples from nineteenth-century spectroscopy are explored with diagrams. The aim of this project is the implementation of the causal network in computer language.
Intelligere, Dec 22, 2015
Resumo: O artigo inicia-se com uma descrição da abordagem dos modelos causais em história da ciên... more Resumo: O artigo inicia-se com uma descrição da abordagem dos modelos causais em história da ciência, discutindo a postulação de histórias contrafactuais na ciência. A seguir, caracterizam-se três tipos diferentes de análises contrafactuais que podem ser feitas em ciências históricas, todas favorecidas pela avaliação retrospectiva. A história econômica e tecnológica é caracterizada pela sua razoável previsibilidade; a história da ciência e da matemática pela sua objetividade; e a terceira classe, que engloba a "história virtual" e a evolução biológica, pela sua vasta amplidão de possibilidades futuras. Palavras-chave: modelos causais -avanços científicos -força causalhistória contrafactual -história econômica -Robert William Fogel -história virtual -evolução biológica.
veterinariosnodiva.com.br
Esta dissertação é um estudo do conceito de "ideal de ordem natural" do filósofo da ciência inglê... more Esta dissertação é um estudo do conceito de "ideal de ordem natural" do filósofo da ciência inglês Stephen Toulmin. Investiga-se como Toulmin se coloca no debate a respeito do realismo científico. Ele é citado como um instrumentalista estrito senso, mas apresenta elementos de realismo em sua rejeição da visão "predicionista" da ciência e em sua noção de que enunciados de escopo (domínio de aplicação) são verdadeiros ou falsos. Estuda-se como a noção de ideal de ordem natural pode ser aplicada à biologia alemã do início do século XIX, marcada por duas correntes: a Naturphilosophie romântica e o teleomecanicismo. Esses programas de pesquisa são também caracterizados em termos de teses centrais e teses periféricas. Palavras-chave: ideal de ordem natural, Stephen Toulmin, teleomecanicismo, Naturphilosophie, instrumentalismo, realismo científico, morfotipo.
The Measurement Problem
This chapter reviews the history of the measurement problem in quantum mechanics, from its roots ... more This chapter reviews the history of the measurement problem in quantum mechanics, from its roots in the wave-particle paradox until around 1990. After examining von Neumann’s formulation of the problem, the proposed solutions are examined, separated into objectivist solutions, subjectivist views, the many worlds interpretation, and views that consider the measurement problem to be a pseudoproblem. The debate blossomed in the 1960s, with new versions of von Neumann’s insolubility proofs, the consideration of null-result measurements, and the proposal of non-linear corrections to the Schrödinger equation. In the 1970s and 1980s, new objectivist ideas were put forward, such as the notion that all systems are open, and the theory of stochastic localizations, which merged with the non-linear approach. Many solutions also assumed that the apparatus should be described with infinite degrees of freedom. Experiments have extended the known limits of quantum superpositions, addressing the question of whether macroscopic superpositions are possible.
Este é um estudo filosófico e histórico do argumento de EPR (1935), que defende que a mecânica qu... more Este é um estudo filosófico e histórico do argumento de EPR (1935), que defende que a mecânica quântica é incompleta, e tem sido alvo de intensos debates e críticas desde então. Examino a estrutura lógica do argumento, seguindo comentadores como McGrath, Chibeni e Wessels, e acompanho os primeiros debates envolvendo Einstein, Bohr, Schrödinger, Furry e Bohm. Estudando as primeiras tentativas de testar experimentalmente os chamados estados "entrelaçados", aponto para as semelhanças entre a análise feita por Bohm & Aharonov (1957) do experimento de Wu & Shaknov (1950), para a polarização de raios gama, e a desigualdade de Bell (1964). O debate sobre incompletude se transformou com o trabalho de Bell, que obteve um dilema segundo o qual deve-se abandonar ou o realismo (uma tese filosófica) ou a localidade (uma tese física), ou seja, descartar teorias realistas locais. A partir deste dilema, e de um dilema derivado do trabalho de EPR, derivo um argumento a favor da nãolocalidade independente da tese do realismo.
Filosofia Unisinos, Mar 15, 2021
The "colored-brain thesis", or strong qualitative physicalism, is discussed from historical and p... more The "colored-brain thesis", or strong qualitative physicalism, is discussed from historical and philosophical perspectives. This thesis was proposed by Thomas Case (1888), in a non-materialistic context, and is close to views explored by H. H. Price (1932) and E. Boring (1933). Using Mary's room thought experiment, one can argue that physicalism implies qualitative physicalism. Qualitative physicalism involves three basic statements: (i) perceptual internalism, and realism of qualia; (ii) ontic physicalism, charaterized as a description in space, time, and scale; and (iii) mind-brain identity thesis. In addition, (iv) structuralism in physics, and distinguishing the present version from that suggested by H. Feigl and S. Pepper, (v) realism of the physical description. The "neurosurgeon argument" is presented, as to why the greenness of a visually perceived avocado, which (according to this view) is present in the brain as a physical-chemical attribute, would not be seen as green by a neurosurgeon who opens the observer's skull. This conception is compared with two close views, Russellian (and Schlickian) monisms and panprotopsychism (including panqualityism). According to the strong qualitative physicalism presented here, the phenomenal experience of a quale q is identical to a physico-chemical quality q, which arises from a combination of (1) the materiality ω associated with the brain, and (2) the causal organization or structure of the relevant elements of the brain ∑, including in this organization the structure of the self: (∑ω) q. The "explanatory gap" between mental and physical states is shifted to a gap between the physico-chemical qualities q and the organized materiality of a specific brain region (∑ω) q , and is seen as being bridged only by a set of non-explanatory postulates.
Acta Scientiarum. Human and Social Sciences, Dec 15, 2020
Examinam-se os estudos de Benjamin Libet e colaboradores, nas décadas de 1960-70, a respeito da p... more Examinam-se os estudos de Benjamin Libet e colaboradores, nas décadas de 1960-70, a respeito da pré-datação temporal. Após estudos de estimulação elétrica direta do córtex somatossensorial, que demora meio segundo para tornar-se consciente, Libet refinou a tese clássica do 'presente ilusório', defendendo que processos conscientes em geral demorariam em torno de meio segundo para se formar. A seguir, explorou o efeito de mascaramento realizando experimentos envolvendo estímulo sensorial (uma picada na mão) seguido pelo estímulo cortical, e por fim concluiu que ocorre uma pré-datação da experiência consciente da picada (sentida meio segundo depois) para um instante de tempo próximo daquele em que de fato ocorreu. Este resultado foi interpretado por alguns filósofos e neurocientistas como sendo um desafio para a tese da identidade mente-encéfalo, provocando uma reação de Patricia Churchland de negar a validade do experimento ou do conceito de pré-datação. Argumentamos que tal reação negativa não se justifica, e que os experimentos são consistentes com uma visão fisicista. Palavras chave: consciência; tempo psicológico; pré-datação; presente ilusório; fisicismo; identidade mente-encéfalo. Time and consciousness: the studies on antedating by Benjamin Libet ABSTRACT. The studies of Benjamin Libet et al. in the 1960s-70s regarding temporal antedating are examined. After studying the direct electrical stimulation of the somatosensory cortex, which takes half a second to become conscious, Libet refined the classic thesis of the 'specious present', arguing that conscious processes generally take around half a second to form. Next, he explored a masking effect by carrying out experiments involving a sensory stimulus (a prick in the hand) followed by cortical stimulation, concluding that there is an 'antedating' of the conscious experience of the pinch (felt half a second later) for an instant of time close to the one when it actually occurred. This result was interpreted by some philosophers and neuroscientists as being a challenge to the mind-brain identity thesis, provoking a reaction by Patricia Churchland of denying the validity of the experiment or the concept of antedating. We argue that such a negative reaction is not justified, and that the experiments are consistent with a physicalist view.
Counterfactual Histories: The Beginning of Quantum Physics
Philosophy of Science, Sep 1, 2001
This paper presents a method for investigating counterfactual histories of science. A central not... more This paper presents a method for investigating counterfactual histories of science. A central notion to our theory of science are "advances" (ideas, data, etc.), which are units passed among scientists and which would be conserved in passing from one possible history to another. Advances are connected to each other by nets of causal influence, and we distinguish strong and weak influences. Around sixty types of advances are grouped into ten classes. As our case study, we examine the beginning of the Old Quantum Theory, using a computer to store and process historical information. We describe four plausible possible histories, along with six other implausible ones.
Principia: An International Journal of Epistemology, Dec 31, 2013
This paper is the first step in an investigation of whether microscopic events can be reduced to ... more This paper is the first step in an investigation of whether microscopic events can be reduced to a mereological composition of elementary events, especially in biological systems. The hypothesis is made that, between events in which quanta are exchanged, there is causal flow, but strictly speaking no events take place. A causal event is characterized by the possibility of an intervention or manipulation. Thus, three types of quantum mechanical events may be found: (1) detection of a quantum of energy; (2) confinement by an apparatus in a Glauber coherent state; (3) null result measurement (without exchange of quanta). The paper explores these three types of elementary causal events, e sets forth as the next step the investigation of the causal events involved in the action of a molecular motor.
This is a study of types of causative present events in a molecular motor, which are proteins - s... more This is a study of types of causative present events in a molecular motor, which are proteins - such as myosin, kinesina and dynein - present inside the cells and associated with, among other functions, the transport of substances along microtubules rails ( Spudich, 2006). Molecular motors are essential for the whole body movement and play an important role in brain. It is known that their malfunction is associated with Alzheimer's disease (Stokin & Goldstein, 2006), and it is reasonable to assume that they are at the base of the deliberative processes of decision making.
Adopt a general perspective that can be characterized as a "methodological reductionism", to try to reduce the macroscopic causality recognized in biology the most basic causal events. A causal event is defined by the possibility of an intervention or manipulation. In a previous study, we identified three types of causal events in quantum systems (less than 0.1 nm) interacting with macroscopic measuring devices (Person, 2013).
In this study, we set aside the quantum scale and up to three orders of magnitude study the causal processes in macromolecules 50nm, immersed in an aqueous solution of the cell medium and described by classical physical chemistry. On this scale, the molecules receive the shock of a huge number of water molecules per second, which makes them around, rotating, vibrating and twisting stochastically in Brownian motion, with power of 10-8 watts order. The macromolecule relates to microtubule (in the case of kinesina and dynein) by means of two "feet", and detaches when one occurs hydrolysis of ATP molecule, a process whose full power for a macromolecule is only 10-16 watts. Even with extremely low power to the Brownian motion, the hydrolysis of ATP is essential for unidirectional movement of the protein. The molecular motor floating end along the microtubule towards the core or the core in the opposite direction. On average, however, dynein has a net shift towards the core (electrically more negative) and kinesina in the opposite direction (more positive charge). Understanding the mechanism involved is the result of research of the past 25 years, and will be presented briefly (Astumian, 2010).
Identify at least four types of causal events are present at the molecular motor movement.
(1) The Brownian motion of the macromolecule can be reduced to a set of individual collisions with water molecules, which provides power to the molecule explore the area available to it, the viscous medium. This is random mechanical causes.
(2) The molecular motor is attached to the microtubule by electrostatic attraction, with a key-lock type fitting. Such a fitting can be regarded as a causal event. If one foot is loose, it stochastically explore all its accessible region can be fixed in microtubule tens of nanometers more forward.
(3) To be able action molecular engine, it is essential frequent conversion of ATP molecule present in the aqueous solution to ADP + P, a hydrolysis process which occurs stochastically. In this chemical reaction, the release of a quantum of energy occurs, which leads to a change in the conformation of the protein molecules and release of a foot.
(4) To explain the existence of molecular motors and the efficient exercise of its biological function of transport and movement, one must take into account root causes associated with natural selection. There is actually a whole family of evolutionary lineages of molecular motors.
A presente obra é marcada por um estilo de reflexão temática, que ressalta a preocupação dos auto... more A presente obra é marcada por um estilo de reflexão temática, que ressalta a preocupação dos autores com os rumos do avanço exponencial da tecnologia na vida humana. Essa preocupação está aqui delimitada aos estudos nas áreas de Filosofia da Mente, Ciência Cognitiva, Semiótica e Filosofia da Informação. Alguns dos pesquisadores dessas áreas têm verificado, com surpresa, recentes aplicações de teorias, hipóteses e conceitos desenvolvidos durante anos de pesquisa na elaboração de projetos que parecem escapar do controle de seus idealizadores. Exemplos dessa experiência surpreendente podem ser constatados nas recentes aplicações de pesquisas da Inteligência Artificial e da Ciência Cognitiva no projeto transhumanista, que visa a realização de um suposto aprimoramento da condição humana, Filosofia da Mente, Ciência Cognitiva e o pós-humano para onde vamos através de recursos da computação inteligente, da bioquímica, da nanotecnologia e da genética. No campo político e ético constatam-se aplicações bélicas, altamente polêmicas, por exemplo, como a aeronave autônoma de bombardeio Taranis.
TECCOGS : Revista Digital de Tecnologias Cognitivas, Dec 15, 2023
Resumo: Uma exposição didática sobre a física quântica abre o artigo, salientando-se a diferença ... more Resumo: Uma exposição didática sobre a física quântica abre o artigo, salientando-se a diferença entre a parte objetiva da teoria e sua parte interpretativa. Adota-se uma "interpretação ondulatória realista com colapsos" para expor cinco princípios básicos da teoria. Aborda-se então a questão de qual é o impacto da física quântica sobre a sociedade. Discorre-se sobre seu grande impacto científico e tecnológico, e em seguida examina-se com mais atenção o seu impacto teórico, em termos ontológico e epistemológico. Argumenta-se que impacto ontológico em nossa vida cotidiana se limita às aplicações tecnológicas, e que possíveis consequências filosóficas do princípio de incerteza e do indeterminismo não são importantes, e muito menos as consequências imaginadas pelo Misticismo Quântico com relação ao emaranhamento. Dentre as lições epistemológicas está que conhecemos a interpretação que mais se aproxima da verdade, mas não sabemos qual é ela, dentre as dezenas de interpretações propostas. Por fim, discutimos a tese de Forman, que envolve a questão de se a ciência é objetiva ou se é uma construção sócio-culturalmente negociada, como defende o relativismo. Concluímos por um "relativismo relativo": as interpretações podem ser fortemente influenciadas pela cultura, mas em uma ciência saudável a sua parte objetiva consegue se isolar das vicissitudes sociais e das intenções emotivas dos cientistas. Por fim, são dados alguns exemplos de influência da cultura, e de outros fatores, sobre as interpretações da Teoria Quântica.
Uma defesa cautelosa do ceticismo científico
Emergence of Autonomy in Contemporary Artificial Agents: Any Novelty?
Cybernetics and Human Knowing, 2008
ABSTRACT The article by Arnellos, Spyrou and Darzentas discusses the question of whether an artif... more ABSTRACT The article by Arnellos, Spyrou and Darzentas discusses the question of whether an artificial system, such as a robot or artificial life, can be made genuinely autonomous. The negative answer that they present is sound, but seems to us to be a simple consequence of the definitions adopted. We argue that the theoretical considerations presented, based on the notions of functional emergence and meaning, need further explanation in order to give support for their argument. As it is presented so far, not very much novelty is added to the already existent research on autonomous and cognitive robotics and artificial life. Also, we would like to challenge the defenders of the 'theory of self-referential systems' to set up conditions in which the theory would be considered falsified. The problem of whether life and autonomy could in principle be sustained with components other than carbon-
Entrevista com Osvaldo Pessoa Junior
Quando a abordagem histórica deve ser usada no ensino de ciências
Ciência & Ensino (ISSN 1980-8631), Sep 14, 2006
Measurement in Quantum Physics: Experimental and Formal Approaches
PhDT, 1990
ABSTRACT
Causal Models in the History of Science
Croatian Journal of Philosophy, Jul 1, 2005
The investigation of a method for postulating counterfactual histories of science has led to the ... more The investigation of a method for postulating counterfactual histories of science has led to the development of a theory of science based on general units of knowledge, which are called "advances". Advances are passed on from scientist to scientist, and may be seen as "causing" the appearance of other advances. This results in networks which may be analyzed in terms of probabilistic causal models, which are readily encodable in computer language. The probability for a set of advances to give rise to another advance is taken to be invariant through history, but depends on a typical time span which is an inverse function of the degree of development of science. Examples are given from the early science of magnetism and from the 19 t h century physics.
The Causal Strength of Scientific Advances
Boston studies in the philosophy of science, 2011
ABSTRACT This paper starts by presenting an overview of an approach to the theory of science base... more ABSTRACT This paper starts by presenting an overview of an approach to the theory of science based on units of scientific knowledge, named “advances”, connected by probabilistic causal relations. The notion of the “causal strength” of an advance is then introduced, and examples from nineteenth-century spectroscopy are explored with diagrams. The aim of this project is the implementation of the causal network in computer language.
Intelligere, Dec 22, 2015
Resumo: O artigo inicia-se com uma descrição da abordagem dos modelos causais em história da ciên... more Resumo: O artigo inicia-se com uma descrição da abordagem dos modelos causais em história da ciência, discutindo a postulação de histórias contrafactuais na ciência. A seguir, caracterizam-se três tipos diferentes de análises contrafactuais que podem ser feitas em ciências históricas, todas favorecidas pela avaliação retrospectiva. A história econômica e tecnológica é caracterizada pela sua razoável previsibilidade; a história da ciência e da matemática pela sua objetividade; e a terceira classe, que engloba a "história virtual" e a evolução biológica, pela sua vasta amplidão de possibilidades futuras. Palavras-chave: modelos causais -avanços científicos -força causalhistória contrafactual -história econômica -Robert William Fogel -história virtual -evolução biológica.
veterinariosnodiva.com.br
Esta dissertação é um estudo do conceito de "ideal de ordem natural" do filósofo da ciência inglê... more Esta dissertação é um estudo do conceito de "ideal de ordem natural" do filósofo da ciência inglês Stephen Toulmin. Investiga-se como Toulmin se coloca no debate a respeito do realismo científico. Ele é citado como um instrumentalista estrito senso, mas apresenta elementos de realismo em sua rejeição da visão "predicionista" da ciência e em sua noção de que enunciados de escopo (domínio de aplicação) são verdadeiros ou falsos. Estuda-se como a noção de ideal de ordem natural pode ser aplicada à biologia alemã do início do século XIX, marcada por duas correntes: a Naturphilosophie romântica e o teleomecanicismo. Esses programas de pesquisa são também caracterizados em termos de teses centrais e teses periféricas. Palavras-chave: ideal de ordem natural, Stephen Toulmin, teleomecanicismo, Naturphilosophie, instrumentalismo, realismo científico, morfotipo.
The Measurement Problem
This chapter reviews the history of the measurement problem in quantum mechanics, from its roots ... more This chapter reviews the history of the measurement problem in quantum mechanics, from its roots in the wave-particle paradox until around 1990. After examining von Neumann’s formulation of the problem, the proposed solutions are examined, separated into objectivist solutions, subjectivist views, the many worlds interpretation, and views that consider the measurement problem to be a pseudoproblem. The debate blossomed in the 1960s, with new versions of von Neumann’s insolubility proofs, the consideration of null-result measurements, and the proposal of non-linear corrections to the Schrödinger equation. In the 1970s and 1980s, new objectivist ideas were put forward, such as the notion that all systems are open, and the theory of stochastic localizations, which merged with the non-linear approach. Many solutions also assumed that the apparatus should be described with infinite degrees of freedom. Experiments have extended the known limits of quantum superpositions, addressing the question of whether macroscopic superpositions are possible.
Este é um estudo filosófico e histórico do argumento de EPR (1935), que defende que a mecânica qu... more Este é um estudo filosófico e histórico do argumento de EPR (1935), que defende que a mecânica quântica é incompleta, e tem sido alvo de intensos debates e críticas desde então. Examino a estrutura lógica do argumento, seguindo comentadores como McGrath, Chibeni e Wessels, e acompanho os primeiros debates envolvendo Einstein, Bohr, Schrödinger, Furry e Bohm. Estudando as primeiras tentativas de testar experimentalmente os chamados estados "entrelaçados", aponto para as semelhanças entre a análise feita por Bohm & Aharonov (1957) do experimento de Wu & Shaknov (1950), para a polarização de raios gama, e a desigualdade de Bell (1964). O debate sobre incompletude se transformou com o trabalho de Bell, que obteve um dilema segundo o qual deve-se abandonar ou o realismo (uma tese filosófica) ou a localidade (uma tese física), ou seja, descartar teorias realistas locais. A partir deste dilema, e de um dilema derivado do trabalho de EPR, derivo um argumento a favor da nãolocalidade independente da tese do realismo.
Filosofia Unisinos, Mar 15, 2021
The "colored-brain thesis", or strong qualitative physicalism, is discussed from historical and p... more The "colored-brain thesis", or strong qualitative physicalism, is discussed from historical and philosophical perspectives. This thesis was proposed by Thomas Case (1888), in a non-materialistic context, and is close to views explored by H. H. Price (1932) and E. Boring (1933). Using Mary's room thought experiment, one can argue that physicalism implies qualitative physicalism. Qualitative physicalism involves three basic statements: (i) perceptual internalism, and realism of qualia; (ii) ontic physicalism, charaterized as a description in space, time, and scale; and (iii) mind-brain identity thesis. In addition, (iv) structuralism in physics, and distinguishing the present version from that suggested by H. Feigl and S. Pepper, (v) realism of the physical description. The "neurosurgeon argument" is presented, as to why the greenness of a visually perceived avocado, which (according to this view) is present in the brain as a physical-chemical attribute, would not be seen as green by a neurosurgeon who opens the observer's skull. This conception is compared with two close views, Russellian (and Schlickian) monisms and panprotopsychism (including panqualityism). According to the strong qualitative physicalism presented here, the phenomenal experience of a quale q is identical to a physico-chemical quality q, which arises from a combination of (1) the materiality ω associated with the brain, and (2) the causal organization or structure of the relevant elements of the brain ∑, including in this organization the structure of the self: (∑ω) q. The "explanatory gap" between mental and physical states is shifted to a gap between the physico-chemical qualities q and the organized materiality of a specific brain region (∑ω) q , and is seen as being bridged only by a set of non-explanatory postulates.
Acta Scientiarum. Human and Social Sciences, Dec 15, 2020
Examinam-se os estudos de Benjamin Libet e colaboradores, nas décadas de 1960-70, a respeito da p... more Examinam-se os estudos de Benjamin Libet e colaboradores, nas décadas de 1960-70, a respeito da pré-datação temporal. Após estudos de estimulação elétrica direta do córtex somatossensorial, que demora meio segundo para tornar-se consciente, Libet refinou a tese clássica do 'presente ilusório', defendendo que processos conscientes em geral demorariam em torno de meio segundo para se formar. A seguir, explorou o efeito de mascaramento realizando experimentos envolvendo estímulo sensorial (uma picada na mão) seguido pelo estímulo cortical, e por fim concluiu que ocorre uma pré-datação da experiência consciente da picada (sentida meio segundo depois) para um instante de tempo próximo daquele em que de fato ocorreu. Este resultado foi interpretado por alguns filósofos e neurocientistas como sendo um desafio para a tese da identidade mente-encéfalo, provocando uma reação de Patricia Churchland de negar a validade do experimento ou do conceito de pré-datação. Argumentamos que tal reação negativa não se justifica, e que os experimentos são consistentes com uma visão fisicista. Palavras chave: consciência; tempo psicológico; pré-datação; presente ilusório; fisicismo; identidade mente-encéfalo. Time and consciousness: the studies on antedating by Benjamin Libet ABSTRACT. The studies of Benjamin Libet et al. in the 1960s-70s regarding temporal antedating are examined. After studying the direct electrical stimulation of the somatosensory cortex, which takes half a second to become conscious, Libet refined the classic thesis of the 'specious present', arguing that conscious processes generally take around half a second to form. Next, he explored a masking effect by carrying out experiments involving a sensory stimulus (a prick in the hand) followed by cortical stimulation, concluding that there is an 'antedating' of the conscious experience of the pinch (felt half a second later) for an instant of time close to the one when it actually occurred. This result was interpreted by some philosophers and neuroscientists as being a challenge to the mind-brain identity thesis, provoking a reaction by Patricia Churchland of denying the validity of the experiment or the concept of antedating. We argue that such a negative reaction is not justified, and that the experiments are consistent with a physicalist view.
Counterfactual Histories: The Beginning of Quantum Physics
Philosophy of Science, Sep 1, 2001
This paper presents a method for investigating counterfactual histories of science. A central not... more This paper presents a method for investigating counterfactual histories of science. A central notion to our theory of science are "advances" (ideas, data, etc.), which are units passed among scientists and which would be conserved in passing from one possible history to another. Advances are connected to each other by nets of causal influence, and we distinguish strong and weak influences. Around sixty types of advances are grouped into ten classes. As our case study, we examine the beginning of the Old Quantum Theory, using a computer to store and process historical information. We describe four plausible possible histories, along with six other implausible ones.
Principia: An International Journal of Epistemology, Dec 31, 2013
This paper is the first step in an investigation of whether microscopic events can be reduced to ... more This paper is the first step in an investigation of whether microscopic events can be reduced to a mereological composition of elementary events, especially in biological systems. The hypothesis is made that, between events in which quanta are exchanged, there is causal flow, but strictly speaking no events take place. A causal event is characterized by the possibility of an intervention or manipulation. Thus, three types of quantum mechanical events may be found: (1) detection of a quantum of energy; (2) confinement by an apparatus in a Glauber coherent state; (3) null result measurement (without exchange of quanta). The paper explores these three types of elementary causal events, e sets forth as the next step the investigation of the causal events involved in the action of a molecular motor.
Studies in computational intelligence, 2010
This paper is an overview of an approach in the philosophy of science of constructing causal mode... more This paper is an overview of an approach in the philosophy of science of constructing causal models of the history of science. Units of scientific knowledge, called "advances", are taken to be related by causal connections, which are modeled in computers by probability distribution functions. Advances are taken to have varying "causal strengths" through time. The approach suggests that it would be interesting to develop a causal model for scientific reasoning. A discussion of counterfactual histories of science is made, with a classification of three types of counterfactual analyses: (i) in economic and technologic history, (ii) in the history of science and mathematics, and (iii) in social history and evolutionary biology. 1 The Model: Advances Connected by Causal Relations This paper is part of a project of developing a computational model that describes the history of science. Such a representation stays close to the narrative of the historian of science, who writes about ideas, discoveries, instruments, theories, etc., each of which exerts influences, in differing degrees, on the appearance and confirmation of other scientific advances. These units of scientific knowledge, which are explicitly or tacitly passed among scientists, will be called advances (even though they might not be a positive contribution to the progress of science). The prototype of an advance is an idea, but there are other types of theoretical advances, such as explanations, laws, problems, theory development, as well as experimental advances, such as data, experiments, and instruments. Other advances include the comparison
Open Philosophy, Dec 13, 2019
An extended definition of "observation" is developed in order to account for the usage in the phy... more An extended definition of "observation" is developed in order to account for the usage in the physical sciences and in neuropsychology. An observation is initially defined as a perception that has a focus of attention and is guided by theoretical considerations. Since the focus may change, one adopts a pluralist position according to which the object of perception may involve any stage of the causal chain that leads to perception, such as the source of light or sound, the obstructions, the medium or even the receptor. The "neutral" observations of the empiricists are seen as involving only low-level or mediumlevel theorization. Examples are examined, such as a lunar eclipse, the rainbow, and observations mediated by instruments, whose "artifacts" are considered observations of the instrument itself. One also defines null-effect observations. Observations of photographs and drawings may be considered either the observation of a printed sheet of paper or the observation of the pictured object or people. This causal-pluralist metatheory of observation also accepts that one may "observe light", observe the retina, and observe parts of the brain which are outside the region of the "sensorium". Illusions and hallucinations are analyzed within this "observational materialism", which considers that qualia are self-observations of the brain. Criticisms that the approach is too wide in scope are analyzed in the conclusion.