Showing posts with label Frege. Show all posts
Showing posts with label Frege. Show all posts

Thursday, May 16, 2024

Where is the mind and what’s a thought?

Originally published on Language and Philosophy, July 12, 2022

If you’ve been to the movies you know how it goes. You buy your ticket, you enter the theater — giant, spacious room with lots of chairs. You walk up the aisle to the very back of the room where you find a narrow door. You open the door. Walking through, you find a steep staircase, almost a ladder. When you get to the top, not far, maybe ten feet, you’re in the projection room. You bring up a chair, sit down and watch the film — that narrow band of plastic on a big spool — feed through a light and lens. After watching the spool spin around for 90 minutes or so, if you’re lucky not longer, til the entire film has passed through the projector and the projector stops and goes dark. You get up and if you’re with a friend you complain that all the movies made today are all alike.

That’s what you do at the movies, no?

No? But you came to see the film. The film is in the projector. No??

A common answer to the question “where is the mind” would be “in the brain”. Cartoon thought bubbles don’t attach to the character’s foot or hand or bottom, but to the head. It wouldn’t have always been so. The Greeks thought the mind was housed in the heart. After all, the mind is always at work, and so is the heart. The emotions, they thought, were generated in the neck and that’s why the neck swells with arteries when we’re really angry. But did they suppose that the mind and emotions were actually in these organs of the body? Seems like an odd notion.

In our culture, the sciences have taken on the role of explaining and interpreting all the world and everything in it. There was a time when whales were fish. If you swim in the ocean, and you have fins and a tail, you’re a fish. No one had a problem with this simple, transparent definition. I don’t see any problem with it. Whales were fish. Makes obvious sense. But now they’re not.

It’s not that the whales have changed. We categorize things differently since Darwin. We’ve got a theory that explains more than the simpler what-you-get-is-what-you-see category. The Darwin story not only explains all sorts of differences between whales and other fish, but also relates them to an explanation for all life forms, much more powerful than ‘some things live and swim in the water, other things walk on land’.

And the same with the mind. The ancients thought the brain was useless jelly — worse than useless, it can’t be preserved so mummification had to exclude the brain. Presumably that’s why the afterlife is so full of zombies and why zombies are always in search of brains. Now we know that the heart doesn’t produce ideas, but the brain does. And this schema of brain=mind has been expanded in our computer age. The brain is a machine that computes the mind inside the skull. And the skull, which had been thought an insensible, inflexible rock devoid of life and thought, has a reason for its inflexible, insensible hardness — to protect that priceless jelly, the one piece of our body that can’t be replaced. No such thing as a brain transplant. You is that brain.

But is the mind inside the brain? This is a fundamental misconception of our culture. I say fundamental because what could be more fundamental than the mind? It’s the all in all of you. And yet we’ve located in the wrong place entirely. That’s a big misconception, not a minor one. And it’s probably why we’re confused about whether computers can be intelligent. If you’ve got a completely wrong notion of where your mind is, how could you come up with a good understanding of machine intelligence beyond the Turing Test, this behavioristic expression of despair over this very misunderstanding? 

But this brain=mind schema is all wrong, as you can see when you go the movies. The film is in the projector, no question. But the movie is not. The movie is on the screen. The mind is not at all in the brain. The film and the movie are two different categories of matter. There’s a causal relation, but cause and effect can be of very different things. The paint spread over a stencil has no relation to the meaning of the symbol it causes. No relationship: you could use a different color paint, or you could use dust, or you could generate the same symbol by holding the stencil in front of a shining light, or write the symbol by hand without the stencil at all or type it on a keyboard. Whatever in your brain is generating mind, it is of a different and unrelated kind, just as paint or ink are different in kind from the meaningful symbol.  

So if the movie is not in the projector, where is the mind? Well, it’s obvious. The mind, of course, is everything we see, hear, touch, think about and even our physical sense of self, our balance or proprioception — everything we sense and think about. The mind is the world we see and experience around us. The mind is that experience. That experience is a mental illusion produced or projected by the brain (see the upcoming post “The easy answer to the hard question, and a research program for it”) through natural selection to help you navigate the real world out there, what Kant called the noumenal world, the things in themselves, which we never get to see, since they are not visible — they don’t have colors, those are just wavelengths. Seeing and colors are our brain interpretation, designed by natural selection to keep us from falling off cliffs and such. Experience — the world we sense, including our sense of ourselves — is just a natural selection accommodation between the noumenal world and our needs in it.

You might add the emotions, since these are also given to us by natural selection to navigate away from the saber-toothed tiger (fear/flight) or engage with an enemy competitor (fight/hate). [Why we have sadness is the great mystery. None of the explanations I’ve heard are persuasive. I’ll try my hand in a later post.] The emotions don’t seem to be in a where. The growing consensus is that emotions are states of physical arousal or lack of arousal, associated with elements of experience and symbolically interpreted.

The brain is the one location of all locations where you can’t find the mind. Someone stabs you in the brain, you won’t feel anything in the brain. It has no sensory nerves. You’ll experience the stab as something else — memory loss, a sudden pain in the foot — something in experience, not in the brain.

It seems astonishing to me that we have this schema of mind-is-in-the-skull. Your mind is, of course, your experience, what you sense, what you see, what you feel. The mind is the world you perceive, including the perception of your body and yourself and your reflexive perception of your mind (not that you dwell on such reflexivity unless you’re smoking up weed for the first time or you’re a Hofstadter stoner). The brain is just the projector. The movie is on the screen, not at all in the projector. Who would ever mistake the two?

For the longest time I was puzzled by thoughts. Okay, I know where the mind is, the mind is everything out there, all of my experience, but what about thoughts? Where are they? Seems so much more elusive than the rest of the mind. You can record and store a thought in symbols on a page, but that’s a representation of the thought, not having a thought. It’s just a means for readers to interpret the symbols so the reader can have the thought.

Okay, we can record or store thoughts in symbols like writing, but that’s not the thought, it’s just a representation of it. Thoughts — the grasping of thoughts, in Frege’s sense — don’t seem to have a where. “Where?” doesn’t apply to them, even though the mind very much does have a where and when — it’s here around me now. As a student of mine said, “Thoughts have no home.” Poetic, but true.

A brilliant programmer friend — I’d name him but he doesn’t like attention — mentioned that Jeff Hawkins had a take on the thought that made sense to him: that the brain is modeling the world. This modeling is what we call thinking. This seem right to me if it’s extended to relations. So, model two buildings one small one large. This can stand for the relation of big and little. After using such models of big and small, two buildings, a plum and a blueberry, an elephant and an ant, a learner applies symbols for these relations “big” and “small” and there you have it. The symbols instantly recall the models that are now as familiar as one’s own thumb. Where are thoughts? They live in the association between the models, which are part of experience, the mind, and the symbols for them. They are not in a where; they are a bit like memories, rehearsed bits of experience abstracted and tied to a symbol. They are a process, a kind of computation: Jerry Fodor’s language of thought and Frege’s grasping of the thought.

No doubt non humans can have thoughts as well without symbols. These too are, I suppose, habits of models, and are associated with emotions derived from natural selection. I’m guessing a dog will know the leader of the pack because dogs have a model of leader of the pack and an instinctual response to it. We humans have the advantage of the mental flexibility to combine our models using symbols and grammars to think all sorts of things about those models. That’s our language of thought. Humans are unusual in our degree of independence of instinct. It’s a property that allows us to be so flexible and adaptive. We follow culture and deliberation along with our instinctual fixed responses.

Where is the thought? It’s a process, the process of reading those strings of symbols and responding to our models that have become second nature.

There’s more to it than that, but that’s enough for this post.


A theory for semantic drift

Originally published on Language and Philosophy, April 1, 2011

Okay, here’s a theory to account for some of the variety in semantic drift, the gradual change of a word’s meaning.

Going back to old Saussure, the sign has two sides, the physical shape (for speech, this is the sound of the word) and what the word means. You’d think that semantic shift would only happen on the meaning side, but semantics plays on both sides of the sign because both sides relate to other signs in the language.

Let’s expand Saussure’s duality a bit with Frege’s distinction between sense (something like idea) and reference (the real world objects determined by the idea). The meaning of the sign can shift if the idea drifts, expanding (losing information) or contracting (becoming informationally richer) or just replacing some information with new information. The many pressures or inclinations on idea drift have been well observed and studied in the literature.

The physical sound-shape side of the sign can be the source of meaning shift as well, odd as that may seem. Why would an arbitrary sound have an effect on meaning? Well, for example, sound shapes in English that bear strong resemblance to Greek or Latin words tend to be treated as more serious and formal than monosyllabic Anglo-Saxon words. That seriousness affects their semantic value. Ask a class of students which endeavor is more fun and which more serious, athletics or sports, and you will get a 90% agreement that sports are a less formal activity, although if you then ask whether they denote the same set of activities, you’ll get 100% agreement that they do (and a puzzled class of students).

Speakers have a blind spot in their linguistic capacity. They have great trouble distinguishing between the word and its meaning. There’s nothing surprising about it: we do a lot of our thinking in words, so the two — thought and word — incline to meld into one another.

So it is also not surprising that the formality of a word can influence its semantic shifts. Our social attitude to a word’s sound-place in the language is part of its meaning.

So far we’ve got the following aspects of meaning:

– idea

– social attitude to the idea and relation of the idea to other ideas

– attitude to the sound shape and the relation of the sound shape to other sound shapes

– reference.

Less observed is the possibility of drift caused by the reference.

The set of real-world objects referred to by a word is determined by the idea. The idea of the word “cat” determines the set of felines. When the idea is employed colloquially as in “hep cat,” the idea determines that “cat” denotes the set of counterculturally acceptable males. Because the referent depends on the idea, drift in the idea has received most scientific attention. But the referent, even though fixed by the idea, can be the source of semantic shift as well, because social attitudes to things is not fixed.
“Democracy” denotes a specific set of government types, but that set has not always been valued in the past as it is today. In the U.S., “democracy” is viewed as almost synonymous with “just” and “right.” It wasn’t always and it need not always be.

Consider the denotation of “woman.” The boundaries of the set haven’t changed, and the properties that make a human a woman haven’t changed, but social attitudes have and the social place of women has. Surely these changes, which relate to the referent, not to the idea or the sound shape, have shifted the meaning.

“God” is another word that has surely shifted through changing attitudes to its referent, though discussing it presents the difficulty of dealing with an elusive referent.

Consider “computer.” The rapid technological advances have altered the set almost beyond recognition, from a room-sized machine exclusive to universities and military labs, to the palm pilot. That’s a reference change that directly shifts the idea.

One reason linguists don’t spend much effort observing reference-based shifts, is that those shifts depend on non linguistic phenomena, and so don’t instruct much about the nature of language itself. It would be useful, however, to learn the extent to which reference shift can be tolerated by a word and the broader linguistic effects of reference shift.

Then there’s metaphor. In a separate post I mentioned that metaphors trade on a few specifics of an analogy. They can dilute information as in

– the foot of the mountain

now means just the bottom — the toes, heel and arch are lost.

This is all just a start, but the point here is that semantic shift can occur on either side of the sign, the reference or the idea, the signified or the signifier.

I’m going to stop here for now, but there’s more in the first post on this blog, which gives a bunch of surprising facts and more surprising dynamics about semantic drift in gender words. The big surprise there is that euphemism frequently causes its opposite, pejoration.