2015年 08月 02日
前史：Cartesian Dualismデカルト的二元論 （each of us consists of a material body subject to the normal laws of physics, and an immaterial mind, which is not） 人間は全く異なる実体である身体と心から成る、身体が滅びても心は滅びない（霊魂の不滅）
*Behaviorism行動主義（B.F. Skinner：mental events can be reduced to stimulus-response pairs） 心は刺激ー反応のシステムにすぎない
*Vienna Circle Verificationism検証主義 （any proposition that was not an a logical truth or which could not be tested was literally meaningless）経験的にテストできない主張は無意味
*Scientific Reductionism科学的還元主義（物理学的説明に還元できるmental eventのみがリアル）、Mind-Brain Identity Theory（Smart1959）：mental states could literally be particular states of the brain – so that for example some C-fibres firing in one’s brain would be identical with a specific feeling of pain.
*他：Gilbert Ryle (1900-1976)デカルトは身体の中にそれとは全く異なる実体である心があるとしている。この解釈では、心は「機械の中の幽霊」と同じ。
20世紀半ば以後(driven by computer metaphors)
*Functionalism機能主義（the important thing about mental states is not where they are located or what they are made of, but what function they perform） Alan Turing、Foder
*Neurological Reductivist Materialism神経還元唯物論：Paul and Patricia Churchland（‘eliminative materialism’, talk of mental states will eventually be abandoned altogether, in favor of a radically different view of how the brain works not identified with brain states. ）Dennett
*Supervenience Theories付随主義：Donald Davidson、Jaegwon Kim(意識やクオリアは火にともなう煙のようなもの、煙同様物質に対して何の因果作用も及ばさない）
*Naturalistic Dualism自然主義的二元論：David Chalmers
現代の標準説： the Cognitive Science Program（equating mental phenomena with operations of the brain, and explaining them all in scientific terms）
*Objections to the Cognitive Science Program: Searle（強いAIは正しくない）, the role of emotions, The Extended Mind〔心の範囲はHDや携帯にも及ぶ）, 汎心論
2015年 08月 01日
* Folk Psychologyについて
First published Mon Sep 22, 1997; substantive revision Thu Aug 12, 2010
The concept of folk psychology has played a significant role in philosophy of mind and cognitive science over the last half century. However, even a cursory examination of the literature reveals that there are at least three distinct senses in which the term “folk psychology” is used.
(1) Sometimes “folk psychology” is used to refer to a particular set of cognitive capacities which include—but are not exhausted by—the capacities to predict and explain behavior.
(2) The term “folk psychology” is also used to refer to a theory of behavior represented in the brain. According to many philosophers and cognitive scientists, the set of cognitive capacities identified above are underpinned by folk psychology in this second sense.
(3) The final sense of “folk psychology” is closely associated with the work of David Lewis. On this view, folk psychology is a psychological theory constituted by the platitudes about the mind ordinary people are inclined to endorse.
To reduce terminological ambiguity, throughout this entry the term “mindreading” will be used to refer to that set of cognitive capacities which include (but is not exhausted by) the capacities to predict and explain behavior. “Folk psychology” will be used only in the second and third senses identified above. When separate names are required to avoid confusion, the second sense of “folk psychology” will be called the mindreading approach to folk psychology and the third sense the platitude approach to folk psychology. This terminology is due to Stich & Nichols 2003. In an earlier publication, Stephen Stich and I called the mindreading sense of folk psychology the internal sense, and the platitude sense the external sense (Stich & Ravenscroft 1994). However, the current labels are more informative.
It's not clear who introduced the term “folk psychology” into the philosophy of mind. It gained wide usage during the 1980s and is rarely used outside philosophy. The phrase “commonsense psychology” is sometimes used by philosophers synonymously with “folk psychology”, although the former term seems to be dying out. Psychologists rarely use “folk psychology”, preferring the phrase “theory of mind” (or sometimes “naïve psychology”). Just as there is ambiguity in the use of “folk psychology”, “theory of mind” is used to refer both to mindreading and to the theory hypothesized to underpin mindreading.
2015年 08月 01日
A more robust form of criticism of the reductionist program comes from a revival of panpsychism by philosophers such as Galen Strawson and Gregg Rosenberg
, and physicists such as Henry Stap
p. They concur with Alfred North Whitehead’s view that for consciousness to be anywhere in nature it must be everywhere in nature, and with William James’ view that our stream of consciousness is open to intrusions 侵入 from an environmentally-pervasive conscious ‘more’. In other words, everything has an element of consciousness.
2015年 08月 01日
(3) The Extended Mind
Other critics of the reductionistic agenda行動計画in the philosophy of mind have pointed out that many aspects of our mental functioning are not brain-bound in the way identity theorists supposed.
The psychologist J.J. Gibson articulated the idea of human thinking as ecologically embedded in a body and an environment. Following this, Andy Clark argues that one’s body, ability to move, and system of environmental affordances, are as much a part of one’s mental functioning as are brain functions.
Clark shifts the philosophical emphasis from analysis of the brain to analysis of a human’s kinesthetic運動感覚のinteraction with an ecological and social space. He points out that large-scale social projects, such as a building project or a disaster relief effort, occur across a considerably extended space and through the intersection of many people’s minds, and are not limited to neuronal firings in any individual brain.
Clark, in a joint paper with David Chalmers
, discusses the fictional example of Otto, a man with memory problems who remembers the location of a library (and other useful pieces of information) by writing it down in a notebook. They argue that Otto’s memory is literally in the notebook, not in his brain. Similarly, much of the memory of all of us
arguablyおそらく間違いなく now resides in a variety of electronic devices
Andy Clark & David J. Chalmers, "The Extended Mind," Analysis 58:10-23, 1998.
2015年 08月 01日
Recent discoveries by Antonio Damasio and Jaak Panksepp
about the role of emotions in decision-making and social reasoning have raised further doubts about the strongly cognitive model of mind inherited from Descartes and perpetuated by the Strong AI /Turing machine model.
Far from being the distractions 注意散漫to mental operations that Plato and Descartes represented them as being, emotions have turned out to be essential elements in mental functioning
. Patients with pre-frontal-cortex brain injuries, like the railroad worker Phineas Gage, or other brain injuries that impair emotional functioning, become incapable of even simple planning. Without emotional drive, cognition appears to become dysfunctional機能障害性の, at least in humans.
2015年 08月 01日
Objections to the Cognitive Science Program
While John Searle agrees with the materialist leanings of the cognitive scientists, he has been arguing that functionalists and eliminativists take the computer model too seriously, as actually descriptive of the functioning of a mind (Strong Artificial Intelligence
) rather than as a helpful metapho
r (Weak AI
The syntax of a sentence is the grammar or logical structure of the sentence. It can be captured through a formulation of this structure in symbolic logic. The semantics of a sentence is its meaning or reference. Searle says that philosophers like Turing, Fodor, the early Putnam and other advocates of Strong AI collapse semantics into syntax
. There are some reasons for doing this. For instance, Turing could translate the code that the Germans were using in World War II using only his syntactic engine, without reference to the meaning of what he was translating. However Searle argues that in the way they operate, languages do not collapse semantics into syntax. He makes this point most clearly through his Chinese Room example.
A person who speaks no Chinese, sitting in a room, has cards with Chinese characters on slipped under the door to him. He has a rule-book for processing these characters, and passes further character cards out of the room according to those rules. A person outside the room interprets the output as someone answering questions in Chinese. Searle says that the ability to string Chinese symbols together according to grammatical or logical rules does not however constitute speaking Chinese, because the person in the room does not understand the reference or meanings of the symbols that a speaker of Chinese would give them. To understand the meanings, one would have to understand not only what the cards refer to, but a lot about Chinese culture, nuances of tone and context, social structure, mannerisms, etc. None of this data is contained in or reducible to the syntactical rules of Chinese
2015年 07月 31日
(4)Naturalistic Dualism and the Hard Problem 自然主義的2元論と意識の難問
, however, argues that materialist reductionism of the Churchlands’ type throws out too much, and cannot deal with the fact that humans enjoy sunsets
. Chalmers agrees with Thomas Nagel
that there is something that it feels like to be a bat, or a human, but there may be nothing that it is like to be a TV set
. (Computers are left an open question).
Chalmers argues that functionalists and reductionists
are only dealing with the ‘easy problems’ of consciousness
. Problems such as how an organism learns, how the sense mechanisms work, how the brain processes sensory input and the like, are all mechanical questions about organic functions, so as one would expect, mechanical explanations are adequate to explain them. The hard problem
, according to Chalmers, is why any of these events should be accompanied by phenomenal experience: what it’s like to see red, for example
. He argues that there are no physical facts about brains from which it follows that phenomenal experience should occur for those and only those physical events for which it does occur. In other words, there’s nothing physically special about the brain which explains experiences. Further, rejecting behaviorism, Chalmers points out that a first-person perspective is required
to even know that phenomenal properties accompany the physical events.
Chalmers argues for a form of dualism that he calls ‘naturalistic dualism
’. To explain consciousness in full, he argues, requires taking phenomenal experience seriously. But, unlike Plato and Descartes, Chalmers believes that the conscious phenomena are dependent on the existence of brain states. This implies that the relationship between the mental states and their biochemical base is scientifically discoverable. Also, the conscious states must mirror the functions performed by the biochemical states in some important ways. Chalmers also calls his position ‘non-reductive functionalism
2015年 07月 31日
(3) Supervenience theories 付随性説
and Jaegwon Kim
agree with the reductionists that only physical and mechanical principles explain anything
. But they insist that phenomenal experience, such as the experience of seeing a sunset, adds something to a human life that a computer might lack
. Kim and Davidson both said that phenomenal qualities are supervenient properties of brains: properties arising simply because the physical processes in the brains were working
. The supervenience of mental phenomena on brain activity like this is understood as paralleling the supervenience of smoke on fires
: the smoke does not causally effect the fire, but will be there, as a by-product, whenever a fire is occurring.
These philosophers thus avoided denying the reality of mental experience
, but the supervenient phenomenal properties are here viewed as playing no causal role in thinking or action. This supervenient view, of mental phenomena being causally-ineffective emergent properties of the brain, is similar to the position in philosophy of mind called epiphenomenalism随伴現象説.
2015年 07月 31日
Paul and Patricia Churchland
espouse 信奉するa position they call ‘eliminative materialism
’, which argues that the project of neuroscience will actually prove to be even more radical than identity theorists like Smart realized. The Churchlands claim that talk of mental states will eventually be abandoned altogether, in favor of a radically different view of how the brain works
not identified with brain states.
adds to the Churchlands’ project a claim that interpreting a system as an intentional and rational system is simply a matter of taking a particular type of stance with respect to the system. To see Big Blue the chess computer as rational and interpret its movement as planning to attack a queen, is simply an admission that we don’t know what design or physical features of Big Blue produced the behavior we observe, and so the behavior appears rational.
＊ポール・チャーチランドは消去主義的唯物論（eliminative materialism）の立場に立ち、素朴心理学 （folk psychology） を激しく攻撃する研究者として有名である。ポールによれば素朴心理学に頻繁に登場する信念や欲求といった概念は、科学史上のフロギストンやカロリック、エーテル、生気といった概念と同種のものであり、脳についての理解が深まったさいには捨て去られるべき概念であるとする。つまり信念や欲求といった心的状態を指し示す言葉は、対応する独自の実在を一切持っておらず、そうした概念はやがて脳の物質的なあり方として神経科学の言葉だけですべて説明されつくされる日がくる
多元的草稿モデル(Multiple Drafts Model)とカルテジアン劇場批判
意識をつかさどる中央処理装置「カルテジアン劇場」(Cartesian Theater)の存在を否定し、それに代わるものとして意識の「多元的草稿理論」(Multiple Drafts Theory)モデルを提唱している。意識とは「カルテジアン劇場」のような中央処理装置をもたない、空間的・時間的に並列した複数のプロセスから織り出され構成されるものだとデネットは論じる（意識のパンデモニアム・モデル）。以上のようなプロセスを経て構成される意識を、デネットは「物語的重力の中心」(Center of Narrative Grativity)と呼んでいる。
2015年 07月 31日
is the theory that the important thing about mental states is not where they are located or what they are made of, but what function they perform
Turing is identifying mental properties with mental function
s – not with observable behavior, as Ryle did; nor with brain states, as Smart did.
Turing assumes mental functions can cause behavior and brain states, but not that they’re identical with either behavior or brain states.
added to the functionalist program the proviso(但し書き)that any function capable of working as brain states do must be computational
. Neurons, structures and patterns in the brain can be described in terms of mathematical models. Therefore if mental events are to be functionally connected to brains in a one-to-one correspondence, then they too must be realizable through a language of thought in a digitizable format.
During the 1960s, various philosophers such as Donald Davidson, Hilary Putnam, and Fodor tried to resolve the puzzle of developing a way to preserve the explanatory efficacy of mental causation and so-called "folk psychology" while adhering to a materialist vision of the world which did not violate the "generality of physics"
. Their proposal was, first of all, to reject the then-dominant theories in philosophy of mind: behaviorism and the type identity theory
. The problem with logical behaviorism was that it failed to account for causation between mental states
and such causation seems to be essential to psychological explanation, especially if one considers that behavior is not an effect of a single mental event/cause but is rather the effect of a chain of mental events/causes. The type-identity theory, on the other hand, failed to explain the fact that radically different physical systems can find themselves in the identical mental state
. Besides being deeply anthropocentric (why should humans be the only thinking organisms in the universe?), the identity-type theory also failed to deal with accumulating evidence in the neurosciences that every single human brain is different from all the others. Hence, the impossibility of referring to common mental states in different physical systems
manifests itself not only between different species but also between organisms of the same species.
An illustration of multiple realizability
. M stands for mental and P stand for physical. The diagram shows that more than one P can instantiate one M, but not vice versa
. Causal relations between states are represented by the arrows (M1 goes to M2, etc.)
One can solve these problems, according to Fodor, with functionalism
, a hypothesis which was designed to overcome the failings of both dualism and reductionism. What is important is the function of a mental state regardless of the physical substrate which implements it. The foundation for this view lies in the principle of the multiple realizability of the mental. Under this view, for example, I and a computer can both instantiate ("realize") the same functional state though we are made of completely different material stuff
(see graphic at right). On this basis functionalism can be classified as a form of token materialism.(Wikipedia)