My university, Soka University, was founded by a new Buddhist movement organization in Japan, Soka Gakkai. I teach contemporary philosophy and philosophy of religion there.
One of the most exciting issues in contemporary philosophy is neurophilosophy (named by Patricia Churchland). This philosophy is influenced by neuroscience and insists a kind of reductive physicalism that human mental activities are reducible to brain activities. This argument challenges a dualistic view of human being in traditional philosophy and religion.
In Japan, Takeshi Yoro also insists brainism (唯脳論), a kind of neurophilosophy, but his argument is not so extreme as neurophilosophy in the USA. He admits some role of religion.
But neurophilosophers in the USA are extremists and they call the traditional dualistic view of human being "folk psychology" and look forward to days in the future when neurophilosophy replaces folk psychology.
When I teach neurophilosophy at my university, many students become perplexed about how to think about their own mind or consciousness, and eventually reject neurophilosophy. Things are the same at another college for scientific discipline. The students admit that mental phenomena have their base in brain activities, but would not like to think that mental activities are nothing but physical activities in the brain.
In my philosophy of religion class, I sometimes ask my students how they think about a worldview in some Buddhist scriptures, for example, about the relationship between the weather and faith. More than half students think that, if the worldview contradicts a scientific worldview accepted by many people, they don't stick to the religious worldview. But some students still support the religious worldview because it is insisted in the religiously important scriptures.
After that, I teach that if Buddha or Nichiren were born in the modern days, he would teach Buddhism in different way because he would be wise enough to understand importance and limits of science, and teach that the founder of Soka Gakkai, Tsunesaburo Makiguchi thought that Buddhism should be compatible with science and he launched himself a new religious movement with a new interpretation about Buddhism. After I teach that religion should change to be well suited for a new cultural society unless it would extinct, some of the students who supported the religious worldview begin to rethink and may change their minds.
Although neuroscience gives us valuable information about brain mechanisms that generate our mental activities, neurophilosophy that is influenced by neuroscience does not give us a happy view of mental activities (at least for my students). I now seek another kind of philosophy that is based on neuroscience and yet gives us a more sound view of mental activities that allows us to hold much of traditional folk psychology.
On the other hand, though I recommend my students to accept a more liberal view of religion that is compatible with science, I wonder to what extent religion can accept neuroscience. Fortunately I can find recent Catholic theological trend that seeks new theology compatible with neuroscience. In my presentation, I would like to show you some features about it, and get your opinion about it.
Here “neurophilosophers” means a kind of philosophers who are influenced by neuroscience and support reductive physicalism that human mental activities are nothing more than physical activities in the brain.
It includes philosophers at the University of California at San Diego or near there; for example, Patricia Churchland (Neurophilosophy 1986, The Computational Brain 1994), Paul Churchland (Matter and Consciousness 1993, The Engine of Reason, the Seat of the Soul 1996 認知哲学), Daniel Dennett (Consciousness Explained 1991解明される意識) and such neuroscientists who argue also philosophical issues; for example, Francis Crick (The Astonishing Hypothesis: The Scientific Search for a Soul 1994 DNAに魂はあるか). Antonio Damasio (Descartes' Error 1994 生存する脳, The Feeling of What Happens 2000) and Ramachandran (Phantoms in the Brain 1998 脳の中の幽霊) are also members of their group but have different opinions.
He quotes from Roman Catholic catechism, “What is the soul? The soul is a living being without a body, having reason and free will.”(Crick, p.3) This is a traditional dualistic view of mind and body.
Against this view Crick proposes his astonishing hypothesis, saying, “Astonishing Hypothesis is that ‘you', your joys and your sorrows, your memories and your ambitions, your sense of personal identity and free will, are in fact no more than the behavior of a vast assembly of nerve cells and their associated molecules...You're nothing but a pack of neurons."(ibid)
This is a physicalistic monistic view of mind and body. He insists that reductive physicalism is true, saying, “The scientific belief is that our minds, the behavior of our brain, can be explained by the interactions of nerve cells and the molecules associated with them.”(ibid, p.7)
Crick defends reductionism, saying, “Why does the Astonishing Hypothesis seem so surprising? ...The first is that many people are reluctant to accept what is often called the ‘reductionist approach'---that a complex system can be explained by the behavior of its parts and their interactions with each other...After all, reductionism is the main theoretical method that has driven the development of physics, chemistry, and molecular biology. ... General philosophical arguments against reductionism will not do.”(ibid, p.7-p.9)
Here we can find a kind of reductive physicalism. But we can also find that this opinion is ‘methodological reductionism’. This reductionism is a research strategy of analyzing the thing to be studied into its parts.
Crick also believes in ‘causal reductionism’, the view that the behavior of the parts of a system is determinative of the behavior of all higher-level entities. He also admits a dynamic interactive process of both levels, saying, “Reductionism is not the rigid process of explaining one fixed set of ideas in terms of another fixed set of ideas at a lower level, but a dynamic interactive process that modifies the concepts at both levels as knowledge develops.”(ibid, p.8)
After all Crick cannot prove yet that causal reductionism or reductive physicalism is true. We also admit that methodological reductionism is important research strategy. But it does not entail that reductive explain is true.
In his informative book, Churchland emphasizes the importance of a neural network model computer instead of a serial computer plus with an inherent program. He thinks animal and human cognitions have their base in their brain activities, especially in neurons' synaptic connections. He uses many examples of the achievements of the neural network computers.
A neural network computer, Cottrell's face-recognizing network can recognize human facial pictures from non-facial pictures. It also can discern male faces from female faces. It can generate categories without a program. (P. Churchland 1995, pp. 45-50)
A minor variant of the face-recognizing network, EMPATH can also recognize familiar emotional states in the face. For example, astonishment, delight, anger. (ibid, pp. 125-127)
Another neural network computer can also work as an acoustic detective device for submarine sonar to discriminate explosive mine echoes from rock echoes. It generates the partition into two exclusive categories: mine echoes and rock echoes. Also, it generates the two prototypical hot spots where typical and uncompromised examples of each category are routinely coded. (ibid, pp. 79-83)
Moreover, a neural network, NETtalk can read English texts coherently without a program that contains a complex set of rules. NETtalk has no comprehension of what it is reading; no gasp whatever of word meaning.
NETtalk manages to do the job of a complex set of explicit pronunciation rules, which needed several man-years in the formation of DECtalk (serial computer with a program of rules), with a single pass through a few hundred neurons kit together by a pattern of connection weights, generating a categorical division into consonants and vowels. (ibid, pp. 84-91)
Elman net, one of the simplest possible forms of recurrent networks can abstract grammatical categories such as noun, verb, and direct object from various English sentences. It generates various grammatically relevant categories.
It includes the three-way distinction between verbs that must be followed by a direct object, verbs that cannot be so followed, and those for which an object is optional. And nouns are divided into animates and inanimates. The former is subdivided into animals and humans, and the latter into food, breakable, and others. The network can discriminate whether or not a complex sentence with relative clauses is correct. (ibid, pp. 137-143)
Churchland thinks that these achievements of neural network computers show how animal and human brains work. Our brain works not with serial computations and program of rules.
He says, "In humans, and in animals generally, the basic unit of cognition is the activation vector. The basic unit of computation is the vector-to-vector transformation. And it is now evident that the basic unit of memory is the synaptic weight configuration. None of these things have anything essential to do with sentences or propositions, or with inferential relations between them. Our traditional language-centered conception of cognition is now confronted with a very different brain-centered conception, one that assigns language no fundamental role at all." (ibid, pp. 322-323)
He also argues against our activities concerning consciousness, saying, "You came to this book assuming that the basic units of human cognition are states such as thoughts, beliefs, perceptions, desires, and preferences. That assumption is natural enough: it is built into the vocabulary of every natural language. ... These assumptions are central elements in our standard conception of human cognitive activity, a conception often called 'folk psychology' to acknowledge it as the common property of folks generally. Their universality notwithstanding, these bedrock assumptions are probably mistaken." (ibid, p. 322)
He insists that although we assume that we think and believe something meaningful, our brain does not use meaningful language. Therefore the brain does not think, and it only works without comprehension. This means that our mental activities do not correctly reflect our brain's activities.
Here I, as well as my students, have to wonder why our brain generates our consciousness; why our brain does not work without our consciousness; what we are doing really while thinking; whether or not our consciousness is unnecessary for our brain.
Although Churchland insists that our brain generates our consciousness and that our assumptions about mental activities are not correct, he does not reply these naive questions.
Furthermore, in his book, Matter and Consciousness, he says, "Our common-sense psychological framework is a false and radically misleading conception of the causes of human behavior and the nature of cognitive activity. … Folk psychology is not an incomplete representation of our inner natures; it is an outright misrepresentation of our internal sates and activities. … Accordingly, we must expect that the older framework will simply be eliminated, rather than be reduced, by a matured neuroscience." (P. Churchland 1988, p. 43)
So he argues for ‘eliminate reductionism’. But I wonder if I am always misguided whenever I think. This idea reminds me of Descartes' malign demons who deceive me whenever I think. Descartes secured the mental entity but he failed to explain what the mental entity was. Churchland insists that consciousness can be reduced to a physical entity, the brain, but I think he fails to explain why consciousness exists rather than does not exist.