Prof. STEVAN HARNAD EXPLAINING THE MIND (PS-KK16.24, PS-430.46) 25-29. March, 1996 Arrangement of the classes: March 25th, Mon.: 4.30-6.30 pm, #405 March 26th, Tue.: 4-6 pm, #301 March 27th, Wed.: 4-6 pm, #201 March 28th, Thu.: 4.30-6.30 pm, #301 March 29th, Fri.: 4-6 pm, #405 The natural way to try to explain the mind is by looking into it. This method is called introspection, and we all do it whenever we think about thinking. The only problem is that no explanation has ever come out of this. We have no idea at all how we perceive, think, understand, remember. If we did have any idea, cognitive psychology would be easy; we could all do it by sitting in our armchairs observing our minds. It's not quite that easy, though, because the real workings of our minds are unconscious: We can't observe them. We can only observe their effects, in what we do and feel. So the real question is: How are we able to do and feel all the things we can do and feel? Explaining what we can do seems as if it would be the easier part, but it turns out to be devilishly difficult; all we have so far is tiny parts of the puzzle. And the feeling part turns out be more difficult still, because it gets us entangled in some deep philosophical problems, especially the "mind/body" problem: Everyone can can see what you do, but only you can feel what you feel, so how can everyone agree on an explanation? Among the things you can do is to see, hear, use, name, and describe the many things around you in the world. We will examine explanations of how your mind manages to do all this: theories of perception, learning, categorisation, and language. We will discuss how things are represented in your mind. We will look especially closely at mental images: Do they explain how we think? Or should we look at how the brain works? Or do machines that can do some of the things we can do give us a clue? Are we like machines? In the background of all of this will be consciousness: If the hard work is done unconsciously, what good is consciousness? Do we really have a choice, or do our brains and biology dictate it all? And if they dictate the humdrum things, like how we see red and how we remember names and faces, do they also explain our creative moments, when we think of something no one else has ever thought of? The mind has not yet been explained. But the basic questions have now been raised. And we think we also have the right means to begin answering them. You will learn the unfolding details of these answers in later courses in cognitive psychology. In this course we will focus on the questions, the means, and the directions in which they promise to take us. LECTURE 1: From Introspectionism to Behaviourism to Cognitivism: Psychology in Search of a Method What is special about psychology is that it deals with the mental and not just the physical. Yet the history of psychology is one of a very uneasy relation with the mental. The Mind/Body Problem Continues to Beset Psychology It is no wonder that psychologists had trouble with the mental in the short lifetime of their field. Philosophers have been struggling with it for centuries. LECTURE 2: Is the Brain the Solution? One natural place to turn in order to shake loose from the mind/body problem is the brain. And the brain reveals some remarkable "disconnections" in mental function. But is it the way to understand the mind? The Mind's Eye: Mental Imagery and Its Discontents The debate about the role of mental imagery virtually created the field of cognitive psychology. Is "I did it in my head using images" a cognitive explanation? LECTURE 3: Mental Models I: Are Mental States Computer States? The most powerful theory of thinking at the moment is that it is some form of computation. What is computation? And can thinking be that? Mental Models II: Or Are Mental States States in a Neural Net? The strongest rival to the theory that thinking is computation is that it is the activity in an interconnected neural network. What can be said for and against that view? LECTURE 4: Learning and Categorisation How does the "blooming, buzzing confusion" we are born into get sorted out into the many objects and events we can recognise and name? Language and Representation How are the categories we recognise and name represented in our heads? And what is language, that it allows us to communicate them to one another? LECTURE 5: Our Darwinian Past How unique is thinking and mental function to our own species? Can our evolutionary past help explain our minds? Consciousness Faced Head-On Can consciousness be investigated directly? Can we measure when a mental event happens? What causal role does consciousness play? Readings are available electronically from: http://cogsci.soton.ac.uk/~harnad/