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John Searle

John Searle is Mills Professor of Philosophy at the University of California, Berkeley, and is noted for contributions to the philosophy of language, philosophy of mind and consciousness, on the characteristics of socially constructed versus physical realities, and on practical reason. He was awarded the Jean Nicod Prize in 2000. Searle is known for his development of a thought experiment, called the "Chinese room" argument, in which he set out to prove that human thought was not simply computation; that a computational process in itself cannot have an "understanding" of events and processes. In his theory, Searle describes a scenario in which a person is isolated in a room. The individual receives pieces of paper marked with Chinese characters from under the door. Even though the person does not understand Chinese, if there is a formal sorting process for the characters then they can be filed into a meaningful order. If the room can be thought of as a computer, Searle believes that the analogy should hold for the entire brain – suggesting that a person's understanding of Chinese is an emergent property of the brain and not a property possessed by any one part. This view thus characterizes consciousness as an emergent phenomenon of the organism that is an entirely physical property (analogous to the way the pressure of a gas in a container is an emergent property of many gas molecules colliding). Intentionality lies at the heart of Searle's Chinese Room argument against computationally derived artificial intelligence, which proposes that since minds have intentionality, but computational processes do not, minds cannot be intentional by virtue of carrying out computations. Searle's books include Mind: A Brief Introduction, The Mystery of Consciousness, Rediscovery of the Mind: Representation and Mind, Consciousness and Language, Intentionality: An Essay in the Philosophy of Mind, and Rationality in Action.

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John Searle Quotes

We've inherited this vocabulary that makes it look as if mental and physical name different realms. And it's part of our popular culture, so we sing songs about your body and your soul or we have saying about how your mind is willing but your flesh is weak, and sometimes the other way around, the flesh is willing but the mind is weak. And we have inherited, not only philosophically but in our religious tradition, we've inherited the idea that there are two quite distinct realms, a realm of the spiritual and a realm of the physical. And I'm fighting against that. I want to say we live in one realm, it's got all of these features, and once you see that then the philosophical mind-body problem dissolves. You're still left with a terrible problem in neurobiology, namely, how does the brain do it, in detail? What are the specific neurotransmitters? What's the neuronal architecture? But I think the philosophical problem, how is it possible that the mental can be a real part of a world that's entirely physical, I think that problem I can solve.

Look at this glass of water, for example. It's liquid. Now, liquidity is a real feature, but the liquidity is explained by the behavior of the molecules, that is, the liquid behavior is explained by the behavior of the molecules, even though the liquidity is just a feature of the whole system of molecules. I can't find a single molecule and say "This one is liquid, this one is wet, I'll see if I can find you a dry one." Similarly, I can't find a single neuron and say "This one is conscious or this one is unconscious." We're talking about features of whole systems that are explained by the behavior of the microelements of those systems. So I think the philosophical problem is resolved. That is, I don't have any worry about the philosophical mind-body problem. But the scientific problem – how exactly does the machinery do it? – that's still very much up for grabs.

Above all, consciousness is a biological phenomenon. We should think of consciousness as part of our ordinary biological history, along with digestion, growth, mitosis and meiosis. However, though consciousness is a biological phenomenon, it has some important features that other biological phenomena do not have. The most important of these is what I have called its `subjectivity'. There is a sense in which each person's consciousness is private to that person, a sense in which he is related to his pains, tickles, itches, thoughts and feelings in a way that is quite unlike the way that others are related to those pains, tickles, itches, thoughts and feelings. This phenomenon can be described in various ways. It is sometimes described as that feature of consciousness by way of which there is something that it's like or something that it feels like to be in a certain conscious state. If somebody asks me what it feels like to give a lecture in front of a large audience I can answer that question. But if somebody asks what it feels like to be a shingle or a stone, there is no answer to that question because shingles and stones are not conscious. The point is also put by saying that conscious states have a certain qualitative character; the states in question are sometimes described as `qualia'.

This question is the famous `mind-body problem'. Though it has a long and sordid history in both philosophy and science, I think, in broad outline at least, it has a rather simple solution. Here it is: Conscious states are caused by lower level neurobiological processes in the brain and are themselves higher level features of the brain. The key notions here are those of cause and feature. As far as we know anything about how the world works, variable rates of neuron firings in different neuronal architectures cause all the enormous variety of our conscious life. All the stimuli we receive from the external world are converted by the nervous system into one medium, namely, variable rates of neuron firings at synapses. And equally remarkably, these variable rates of neuron firings cause all of the colour and variety of our conscious life. The smell of the flower, the sound of the symphony, the thoughts of theorems in Euclidian geometry – all are caused by lower level biological processes in the brain; and as far as we know, the crucial functional elements are neurons and synapses.