The Mind is Flat

Prologue: Literary Depth, Mental Shallows

• The inner, mental world, and the beliefs, motives, and fears it is supposed to contain is, itself, a work of the imagination. We invent interpretations of ourselves and other people in the flow of experience, just as we conjure up interpretations of fictional characters from a flow of written text.
• There is no pre-existing "inner world of thought" from which our thoughts issue. Thoughts, like fiction, come into existence in the instant that they are invented, and not a moment before.
• Introspection is a process not of perception but of invention: the real-time generation of interpretations and explanations to make sense of our own words and actions. The inner world is a mirage.
• The very task of our improvising mind is to make our thoughts and behavior as coherent as possible - to stay "in character" as well as we are able. To do so, our brains must strive continually to think and act in the current moment in a way that aligns as well as possible with our prior thoughts and actions. We are like judges deciding each new legal case by referring to, and reinterpreting, an ever-growing body of previous cases. So the secret of our minds lies not in supposed hidden depths, but in our remarkable ability to creatively improvise our present, on the theme of our past.
• There is no inner world. Our flow of momentary conscious experience is not the sparkling surface of a vast sea of thought - it is all there is.
• Our brain creates new momentary thoughts and experiences by drawing not on a hidden inner world of knowledge, beliefs, and motives, but on memory traces of previous momentary thoughts and experiences.
• Our brain is an engine that creates momentary conscious interpretations not be drawing on hidden inner depths, but by linking the present with the past, just as writing a novel involves linking its sentences together coherently, rather than creating an entire world.
• The whole of thought, whether chess-playing, abstract mathematical reasoning, or artistic and literary creation, is really no more than an extension of perception.
• Our freedom consists not in the ability magically to transform ourselves in a single jump, but to reshape our thoughts and behaviors, one step at a time: our current thoughts and actions are continually, if slowly, reprogramming our minds.
• Common-sense psychology sees our thought and behavior as rooted in reasoning, but a lot of human intelligence seems to be a matter of finding complex patterns.

Part One: The Illusion of Mental Depth

1. The Power of Invention

• The attempt to draw a map, or build a model, of Gormenghast Castle leads to inconsistency and confusion - the descriptions of great hallways and battlements, libraries and kitchens, networks of passages and vast, almost deserted wings can't be reconciled. They are as tangled and self-contradictory as the inhabitants of the castle itself.
• Creating a fictional place is a bit like setting a crossword. Each description provides another clue to the layout of the castle, city, or country being imagined. But as the number of clues increases, knitting them together successfully soon becomes extraordinarily difficult - indeed it rapidly becomes impossible, both for Gormenghast's readers and for Peake himself.
• Stories have to make sense in so many ways: through consistency of plot, character, and a myriad of details.
• With fictional worlds, avoiding inconsistency requires incredible vigilance.
• Even the fictional worlds of Tolkien and Peake are notable too for their sparseness. In real life, everyone has a specific birthday, fingerprint and an exact number of teeth. In fictional worlds, most characters have none of these properties, or any of a million others, whether significant or trivial.
• Anna Karenina's mind is just as vaguely sketched as her body.
• The two characteristics of fiction: Inconsistency and sparseness.
• Whereas the fictional Anna is a sketchy and contradictory character created by Tolstoy's brain, a real Anna would be an equally sketchy and contradictory character, created by her own brain.
• Our beliefs, values, emotions, and other mental traits are, I suggest, as tangled, self-contradictory and incompletely spelled out as the labyrinths of Gormenghast Castle. It is in this very concrete sense that characters are all fictional, including our own. Inconsistency and sparseness are not just characteristics of fiction. They are also the hallmarks of mental life.
• In the work on AI mental systems, at no stage have human beliefs been successfully mined or common-sense theories reconstructed.
• People can fluently generate verbal explanations and justifications of their thoughts and actions; and, whenever parts of those explanations are queried, out will tumble further verbal explanation or justification. But analysis of these streams, however long they continue, shows that they are little more than a series of loosely connected fragments:
  • Chess grandmasters can't really explain how they play chess.
  • Doctors can't explain how they diagnose patients
  • None of us can remotely explain how we understand the everyday world of people and objects. What we say sounds like explanation - but really it is a terrible jumble that we are making up as we go along.
• As we try to explain a natural phenomenon or social situation, each explanation seems to be new, different and typically incompatible with the last one, rather then following from a single set of underlying principles - the explanations of every new scenario just seem to run off on all directions, apparently without limit. Moreover, each step in each explanation can itself be queried. Why does water tend to find a level? Why do ballbearings bounce off each other? Why does sugar change consistency as it enters the bucket of water? And so on.
• Our explanations have holes everywhere and inconsistencies abound. Psychologists talk of the "illusion of explanatory depth" for the bizarre contrast between our feeling of understanding and our inability to produce cogent explanations.
• Whether explaining how a freidge works, how to steer a bicycle, or the origin of tides, we have a feeling of understanding which seems wildly out of balance with the mangles and self-contradictory explanations we actually come up with.
• Our verbal explanations of the physical world - but equally of the social, economic worlds or our moral or aesthetic judgements - turn out not to be a confused description of inner clarity, but a confused description of inner confusion.
• Our verbal explanations and justifications are not reports of stable, pre-formed building blocks of knowledge, coherent theories over which we reason, deep in an inner mental world. They are ad hoc, provisional, and invented on the spot.
• We have vastly underestimated our powers of invention. Our inner oracle is such a good storyteller - so fluent and convincing - that it fools us completely. But the mental depths our mind conjures up are no more real than the world of Gormenghast or Middle Earth. The mind is flat: our mental surface, the momentary thoughts, explanations, and sensory experiences that make up our stream of consciousness is all there is to mental life.
• The analytic tradition in philosophy tried to get language and meaning straight, as a crucial stepping-stone to launch an indirect attack on big philosophical questions, but it did not work.
• Even the structural patterns observed in language - not just its meaning - are a jumble of inconsistent regularities, sub-regularities, and outright exceptions.
• Countless experiences in psychology and behavioral economics have shown just how spectacularly ill-defined and self-contradictory our beliefs and preferences are.
• People routinely supply wildly different answers to exactly the same question even within a few minutes, and their answers to different questions are often inconsistent.
• We may or may not have strong opinions, but these opinions don't - and could not possibly - spring from coherent and fully spelt-out common-sense theories.
• From the perspective of the arts, literature, and humanities, there is a long tradition of seeing people and their actions as the subjects of conflicting, fragmented, and endlessly recreated interpretation. But viewing psychology as part of the arts and humanities is to react to the illusion of mental depth in, I think, precisely the wrong way. A science of the mind requires understanding how the engine of improvisation that is the core of human intelligence can be constructed out of the machinery of the human brain.

2. The Feeling of Reality

• Invented stories are notoriously difficult to distinguish from true stories - both feel real.
• The mind-as-mirror metaphor can't possibly be right - we need a very different viewpoint, that perception requires inference.
• Our brain glimpses, and conceives of, the world fragment by fragment.
• Illusions of depth, which can be both literal and metaphorical are everywhere.
• Outside of where we are attending, the visual periphery is colorless and extremely fuzzy.
• Our attention is in short supply and where we are not attending, things disappear.
• A gaze-contingent screen can track where you are looking at provide meaningful content only there. The window that we read in can be shrunk to just 10-15 charcters, shifted somewhat to the right of the fixation point, because the brain is thinking ahead slightly.
• What happens when the retinal image is suddenly made almost perfectly still?
  • The image begins to disappear, either piece by piece, or in its entirety; all that is left is a uniform grey field which sometimes darkens into black. Then, without warning, the whole image or parts of it spontaneously reappear typically to disintegrate, reorganize, or entirely disappear again.
  • Now and again, the brain re-engages with the only available meaningful signal, and the straight line pops back into view. But not for long - our whirring imagination is continually straining to find new material onto which an interpretation can be imposed.
  • The visible material retained at any moment tends to correspond to continuous regions of the image (ag the upper, lower, or left side) or meaniful units rather than a set of arbitrary fragments.
  • The fragments that the brain locks onto are meaningful patterns, rather than random parts.
• Principles of the operation of perception (and, by extension, thought):
  • We see only meaningful organizations (or, at least, the most meaningful organization the brain can find): visual chunks, patterns and whole letters, numbers, words, rather than a random scatter of fragments.
  • We see just one meaningful organization at a time
  • Other sensory information that is not part of this meaningful organization is largely or even entirely ignored, to the point of becoming invisible.
  • The brain is continually churning: despite the unaccustomed lack of new input, the brain is desperately attempting to disengage from the current organization, and to find another. When it cannot, the image entirely disappears.
• Perceiving is a type of thinking and perhaps the most important type, with all other types of thought being just powerful extensions of perception.
• We think we see a detailed multicolored world, but we don't. This hoax is so astonishing and all-encompassing that it is sometimes known in philosophy and psychology as the "grand illusion".
• The mind itself is an impossible object - it has only the superficial appearance of solidity.

3. Anatomy of a Hoax

• Our perceptual experience is like a narrator who wishes to remain as unobtrusive as possible - we want to know about the story, not the viewpoint of the storyteller.
• While it si possible, not surprisingly, to perceive multiple locations at once, it appears not to be possible to see two colors at once: indeed, it seems that we must switch back and forth between seeing one colored region and another, but hat we do this so quickly and effortlessly that we have the illusion that we are "grasping" two or more colors at the same time.
• A patient with simultagnosia is able to see objects of different distances and sizes - but has no sense of the continuing existence of the rest of the visual world.

4. The Inconstant Imagination

• Our sense of the vividness of the tiger in a picture stems from the fluency with which we can answer any question we wish about its appearance - but the information is created on demand, not loaded into our brains in a single visual gulp.
• We don't "load" vast quantities of information about an object or a scene simultaneously into our memory - but we can have the answer to any question about visual experience available just when we need it.
• Mental imagery, too, is both sparse and contradictory.
• Aren't the realms of fiction, fantasy, and dreams illustrations of the richness of the inner worlds that our minds can construct?
• Our imagination, like visual experience, is a narrow window of lucidity, and what we see through that window is invented - creatively, subtly, intelligently - not merely reported from some fully specified, entirely coherent inner world.
• The "world" of dreams is a fiction, a jumble of fragments and contradictions. Indeed, it is a particularly inchoate fiction: there is no careful author painstakingly attempting to bring the story into some kind of order - merely a succession of capricious imaginative leaps.
• Dreams are improvised stories, with few details sketched in. When our minds create them, we lock onto some specific fragments of information; almost everything else is left utterly blank.
• The inconsistent, sketchy flow of thought is not a projection of a rich and deep inner mental world. Our thoughts are not shadows of an alternative inner reality, to be charted and discovered; they are fictions of our own devising, created moment by moment.
• Graf and Freud's mistake was to confuse literary creation with psychology. They were able to invent a story about Herbert/Hans and his phobia; and they could equally easily have invented a variety of alternative stories. They believed psychology should be science, they practised it as a literary art form.
• We may feel rather unsure exactly about the nature of the inhabitants of our inner world, but plausible candidates would seem to te beliefs, desires, hopes, fears, mental images, logical arguments, justifications, feelings of anxiety, delight, excitement, gloom, contentment, resignation or enthusiasm, flashes of anger or surges of empathy. Our vagueness about quite what our minds contain is by no means accidental - the solidity of our mental furniture is liable to dissolve as soon as we reach out and touch it.

5. Inventing Feelings

• The Kuleshov effect - inserting still images evoking emotions in between images that are part of the action, and seeing these images change the interpretation of the scene.
• The brain interprets each piece of the perceptual input (each face, symbol, object, or whatever) to make as much sense as possible in the light of the wider context.
• Isn't our bodily state just another set of highly ambiguous clues that need to be interpreted, which can be explained in many different ways depending on the situation we are in? Perhaps emotions - including our own emotions, are just fiction too.
• The brain receives rather crude perceptual signals from your own body, indicating that your hear is pumping, and a certain amount of adrenaline is flowing, you are breathing rapidly, etc. But what does it all mean?
• Our feelings do not burst unbidden from within - they do not pre-exist at all. Instead, they are our brain's best momentary interpretation of feedback about our current bodily state, in the light of the situation we are in. We "read" our own bodily states to interpret our own emotions, in much the same way as we read the facial expressions of other people to interpret their emotions.
• Maybe just two physiological dimensions will suffice: one indicating level of arousal and the other indicating like-dislike.
• Plato sees reason and emotion as two horses pulling in opposite directions. But this goes astray from the outset - having an emotion at all is a paradigmatic act of interpretation, and hence of reasoning.
• The two forces are just two different types of reason, with both carrying positive and negative reasons and feelings.
• Far from knowing our own minds, we are endlessly struggling to make sense of our own experiences - and we can often jump to the wrong conclusions. Even attraction, it seems, does not well up from within from some primal source. We feel a surge of adrenaline as attraction rather than experiencing it as fear or anger, because of the circumstances that confront us - our brains, are, moment by moment, attempting to interpret the minimal physiological feedback from our body.
• Emotions have their meaning not through some elementary properties of raw experience, but through their role in our thoughts, our social interactions and our culture.

6. Manufacturing Choice

• The corpus callosum - a massive bundle of more than 200 m nerve fibres, whose role it is to exchange messages between the two hemispheres of the brain.
• Michael Gazzaniga and the "interpreter" - a master of speculation.
• The very ability of the interpreter to create such stories may be crucial to maintaining the sense of the mental unity for the split-brain patient. But for people with normal brains, choices are also naturally and fluently explained after the fact.
• Deciding what to say is a creative act, rather than a read-out from a comprehensive database of my beliefs, attitudes, and values.
• Our beliefs, desires, hopes, and fears do not wait pre-formed in a vast mental antechamber, until they are ushered one by one into the bright light of verbal expression. The left-brain interpreter constructs our thoughts and feelings at the very moment that we think and feel them.
• In a Swedish study, people's responses to a survey were reversed. People are able to effortlessly cook up a perfectly plausible story to justify an opinion that they did not express, just as easily as they are able to justify opinions that they did express. And we are blithely unaware of the difference between the two.
• The interpreter can argue either side of any case; it is like a helpful lawyer happy to defend your words or actions whatever they happen to be at a moment's notice. So our values and beliefs are by no means as stable as we imagine.
• The story-spinning interpreter is not entirely amnesic; and it attempts to build a compelling narrative based on whatever it can remember. It works by referring back to, and transforming, memories of past behavior - we stay in character by following our memories of what we have done before.
• The interpreter does not merely describe our past actions, but helps shape what we do next.
• Even more important than explaining a decision is the aim of being consistent - to make choices that the interpreter can justify and defend. It is so much easier, and so much more convincing to be consistent.
• We attempt continuously to construct our preferences to fit the thoughts that happen to be splashing through our stream of consciousness.
• The brief presence of an American flag in an internet survey had significantly shifter actual voting behavior, a full eight months later! To the extent that I later recall that, when contemplating my political views, I previously found myself leaning to the right, I am a little more likely to lean to the right in the future. To make the most sense of my own behavior, I will aim to think and act as I did before.
• When we make choices, we are not expressing a pre-existing preference at all. What we are doing instead is improvising - making up our preferences as we go along:
  • If we are asked to choose an option, we mostly focus on positive reasons.
  • If we are asked to reject an option, we mostly focus on negative reasons.

Part Two: The Improvised Mind

7. The Cycle of Thought

• Despite being a pudgy bundle of fibres powered by a modest 20 watts of energy, the human brain is by far the most powerful computer in the known universe It can interpret a bafflingly complex sensory worlf, perform a hubes variety of skilled actions, and communicate and navigate a vastly complex physical and social world.
• A PC has one or at most a few processing chips, processing at a phenomenal rate, while the human brain has roughly 100 bn sluggish neurons, linked by roughly 100 tn connections.
• Brain-style computation must result from cooperation across the highly interconnected, but slow, neural processing units, leading to coordinated patterns of neural activity across whole networks or perhaps entire regions of the brain.
• The brain seems to be pretty close to one giant, highly interconnected network (although the connections between different regions of the brain are not equally dense).
• The brain's slow neural units split up the problem into myriad tiny fragments and share their tentative solutions in parallel across the entire, densely interconnected network.
• What is important is that the very fact that the brain uses cooperative computation across vast networks of neurons implies that these networks make one giant, coordinated step at a time rather than, as in a conventional computer, through a myriad of almost infinitesimally tiny information-processing steps. This sequence of giant, cooperative steps, running at an irregular pulse of several "beats" per second, is the "cycle of thought".
• Whatever object or task is engaging our conscious attention will typically engage large swathes of the brain. Accordingly, there will typically be severe interference between any two tasks or problems that engage our conscious attention.
• The entrainment in epilepsy typically starts in a specific region of the cortex, as if the inhabitants of one district are particularly prone to spontaneously launching into Mexican waves - and the nearby neighborhoods are then drawn in, and the wave spreads inexorably across the city.
• Most information from our senses passes through the thalamus before projecting onto the cortex; and information passes in the opposite direction from the cortex through to deep sub-cortical structures to drive our actions.
• The deep brain serves as a relay station between the sensory world and the cortex, and from the cortex back to the world of action. Here, perhaps, somewhere in these deep brain structures, is the crucial bottleneck of attention; and whatever passes through the bottleneck is consciously experienced.
• A "petit mal" episode involves a person, during everyday activity, suddenly adopting a vacant stare and becoming completely unresponsive to their surroundings. Unlike epilepsy, this doesn't spread across the brain but seems to impact the whole brain simultaneously, and leaves no memory after consciousness spontaneously returns.
• No electrical stimulation of the cortex itself could trigger the crisp, immediate, total shutdown of the cortical system, because, Penfold suggested, the "switch" of consciousness lies not in the cortical surface but deep within the brain.
• Our brain is fully engaged with making sense of the information it is confronted with at each moment. Consciousness, and indeed the entire activity of thought, appears to be guided, sequentially, through the narrow bottleneck: deep sub-cortical structures search for, and coordinate, patterns in sensory input, memory and motor output, one at a time. The brain's task is, moment by moment, to link together different pieces of information, and to integrate and act on them right away. Our brain will, of course, lay down fresh memories as this processing proceeds; and draw on the richness of memories of past processing.
• While the cortex is crucial in processing visual information, planning movements and drawing on memories, we are aware of the results of the vast cooperative enterprise across the brain only in so far as the results of such computations reach the sub-cortical gateway structures - these, and not the cortex itself, are the locus of conscious experience.
• Four proposal:
  • Attention is a process of interpretation - The target might be aspects of sensory experience, a fragment of language, or a memory
  • Our only conscious experience is our interpretation of sensory information - All we experience is the stable and meaningful world: we experience the result, not the process.
  • We are conscious of nothing else - Sensory information need not necessarily be gather by our sense, but may be invented in our dreams or by active imagery. and much sensory information comes, of course, not from the external world but from our own bodies - including many of our pains, pleasures, and sensations of effort or boredom. We are conscious of the sounds or shapes of the words we use to encode abstract ideas; or the imagery that accompanies them. But we are not conscious of the abstract ideas themselves, whatever that might mean. Words and images are the objects of consciousness - not the abstract belief.
  • The stream of consciousness is nothing more than a succession of thoughts, an irregular cycle of experiences which are the results of sequential organization of different aspects of sensory input.