The Wandering Mind

by Michael C Corballis

  You can also link these many locations with times, albeit imprecisely. Location, after all, is time, since you can only be in any one location at any one time. You can zoom in time as well, looking back or forward over seconds, minutes, hours, days, weeks, months, years, decades. And all of these mental journeys through time and space are populated with people, events, things, emotions, disappointments, triumphs—the rich fabric of our lives. And although we forget much of what has happened in our lives, we do remember a lot—enough to write biographies or bore our colleagues and children. Our plans are likewise richer than simply taking a new route to work. And then there is the world of fiction, the made-up stories and fantasies that occupy much of our conscious lives—but more of that in Chapter 6.

  When Thomas Suddendorf and I framed the idea of mental time travel, we also outlined additional mental resources needed to construct an imagined episode, whether past or future. We might need an executive processor to build the episode from its constituent parts, a memory buffer to hold information before it fades away. In the previous chapter, I referred to work by Suddendorf and associates implying that children cannot construct fully coherent episodes of past events until they’re about four years old. It may well be stretching credulity to suppose that Walter Ratty has the mental machinery of even a four-year-old child.

  But do these qualities really distinguish our mental travels from those of other creatures? We need to be wary, on the one hand, of the ‘Clever Hans’ error of attributing implausibly human-like qualities to non-human species, but on the other hand of building impregnable mental fortresses that no animal could invade. In a prescient discussion in 2006 on the possible role of the hippocampus in episodic memory, David Smith and Sheri Mizumori wrote:

  We leave it to others to debate whether rodents possess the capacity for consciousness and mental time travel. In any case, the history of psychology is replete with examples of ‘uniquely human’ cognitive functions, which were later demonstrated in so-called lower animals. Given the remarkable homology of mammalian nervous systems and the fact that the ability to explicitly recall previous experiences has such obvious adaptive value, we suggest that, in the absence of contradictory evidence, the most conservative position is to assume that rodents possess an episodic memory system that is qualitatively similar to that of humans.

  Charles Kingsley would surely have applauded. And that other Charles, in Origin of Species, famously wrote: ‘The difference in mind between man and the higher animals, great as it is, certainly is one of degree and not of kind.’

  But there is one place that may be beyond the limits of Walter Ratty’s mental travels, and that may still tell us something about our own mental wanderings that Walter never dreamt of. That comes next.

  5.

  WANDERING INTO OTHER MINDS

  …

  Imagining what it is like to be someone other than yourself is at the core of our humanity.

  —Ian McEwan, from ‘Only Love and Then Oblivion’1

  In the quote that opened this book, as I noted, it was not really Walter Mitty whose mind was wandering. The wanderer was, of course, James Thurber himself, who had ventured into the mind of a fictional character, and set that character mind-wandering on a dangerous mission. In everyday life, as in fiction, we often assume the identities of others. A good actor can transport herself into another person, and carry an audience along with her. Even TV soap operas can take us into other families or situations, and allow us to identify with imaginary people. We habitually judge the personalities of others, try to figure out how they think and act, perhaps to decide whether to employ them, consult them, or marry them.

  The sense that we know what others are thinking has often led people to believe in psychic powers, or telepathy, as though minds can communicate without any contact through the senses. In Chapter 1, I mentioned the German physician Hans Berger, whose fall from a horse was sensed by his sister who was kilometres away and could not have seen or heard the event. Berger thought this might have been an instance of telepathy, but his own attempt to prove an electrical basis for telepathy failed. Nevertheless, many distinguished people have firmly believed that thoughts can be transferred by non-physical means, and even that we can communicate telepathically with the dead—or they with us.

  The idea seems to have been especially popular in late nineteenth-century England. In 1882, the Society for Psychical Research was established in London to investigate telepathy and other so-called psychic phenomena, such as ghosts, trance states, levitations, mediums and communication with the dead. Its first president was Henry Sidgwick, later Professor of Moral Philosophy at Trinity College, Cambridge, and other distinguished members included the experimental physicist Lord Rayleigh, the philosopher Arthur Balfour, who became Prime Minister of England from 1902 to 1905, and Sir Arthur Conan Doyle, author of the Sherlock Holmes stories. The Society attracted famous psychologists such as Sigmund Freud and Carl Jung, and the American psychologist William James was so impressed that he established the American Society for Psychical Research.

  Many people still believe in telepathy, also known as extrasensory perception, or ESP. A 1979 survey of over 1000 academics in the United States showed that 55 per cent of natural scientists, 66 per cent of social scientists and 77 per cent of those in the arts, humanities or education believed that ESP was either established or a likely possibility. Of course, academics will believe almost anything. Psychologists, though, are the spoilsports; for them, the equivalent figure was only 34 per cent, and an equal number believed ESP to be impossible. I doubt that these figures have changed much, or that the beliefs outside of the US are likely to be much different. The stumbling block is that ESP implies an effect that operates at a distance, but without any clear physical medium, such as light, sound, smell, or even radio waves, and this seems both physiologically and physically implausible, or downright impossible.

  Well, maybe not. Some have appealed to the fundamental nature of physical reality. A theorem attributed to the British physicist John Stewart Bell says that any model of reality consistent with quantum mechanics must be non-local. That is, any particles that have once interacted can become entangled, such that when they are later separated, observations on one of the particles can affect what will be observed on its entangled partners. This is true no matter how far apart they are, and is incompatible with any physical signal from one to the other. You might think that this also applies to people, perhaps especially those who have had multiple entanglements with people they know or knew well, such as lovers or marriage partners, and so explains ESP.

  In his 2006 book Entangled Minds: Extrasensory Experiences in a Quantum Reality, the parapsychologist Dean Radin, a one-time engineer and concert violinist, has indeed argued that the physical interactions at a distance implied by Bell’s theorem could explain ESP (also known as psi). He concludes:

  . . . over the past century, most of the fundamental assumptions about the fabric of physical reality have been revised in the direction predicted by genuine psi. This is why I propose that psi is the human experience of the entangled universe. Quantum entanglement as presently understood in elementary atomic systems is, by itself, insufficient to explain psi. But the ontological parallels implied by entanglement and psi are so compelling that I believe they’d be foolish to ignore.

  Maybe if Hans Berger had known more about particle physics, he would have performed a different experiment, but then we would have been denied the discovery of electroencephalography, and perhaps even of the wandering mind.

  As a psychologist, and one who keeps a watchful eye on the field and occasionally tries to make intellectual contact with entangled particles, I remain firmly sceptical. It seems unlikely that entangled particles have anything to do with the human mind. Thousands of experiments have been conducted to test the existence of the paranormal, but the published evidence is unconvincing, especially if one considers that most negative results remain unpublished. Indeed, I was once confronte
d by a group of students who resented my scepticism, and between us we set up a study, but the results were relentlessly negative—and of course remained unpublished (until now).

  Given the wish to believe in disembodied minds, fraudsters have been quick to cash in. One famous example is Uri Geller, an Israeli-British stage performer, who rose to fame in the 1970s for television shows on which he claimed to demonstrate psychic powers. He is perhaps best known for his prowess at bending spoons, apparently through the power of thought—a phenomenon which, if true, is an example of psychokinesis. Geller’s feats are easily duplicated by sleight of hand and spoon, without resort to psychic powers, by stage magicians, including James Randi, who wrote a book entitled The Magic of Uri Geller—it was later called The Truth About Uri Geller. The James Randi Educational Foundation was established in 1996 to further Randi’s work. It offers a $1,000,000 prize to anyone who can demonstrate psychic powers (see www.randi.org if you want to challenge)—and to this day it has not been collected.

  Geller’s exploits were also unmasked, leaving no spoon unbent, in New Zealand by two psychologists, David Marks and Richard Kammann, who were able to repeat his demonstrations on television, again without any claim to psychic powers. They too wrote a book exposing the field of psychic phenomena, and Geller in particular, entitled The Psychology of the Psychic. I recommend these books, but alas they do not have the selling power of books that proclaim the existence of the psychic.

  In spite of the lack of evidence, we humans do seem naturally inclined to believe in powers of the mind to transcend physics, whether through ESP, clairvoyance, telekinesis, or communication with the dead. In part this is probably a matter of wishful thinking. It is comforting to think that the minds of the dead live on, and that we can still communicate with them—or indeed that our own mental lives will soar on after death, unencumbered by the now useless body. The psychologist Paul Bloom, in his book Descartes’ Baby, goes so far as to suggest that we are actually born to be philosophical dualists, like Descartes himself, believing the mind to be separate from the body. Dualism, Bloom suggests, is hard-wired.

  This is not to say, of course, that our minds are in fact separate from our bodies—it’s just that we’re predisposed to believe so. It is indeed difficult to convince most people, except us doughty psychologists and materialistic neuroscientists, that we are merely creatures of flesh and bone, with physical processes inside our heads that dictate our thoughts and actions. The belief in dualism, the idea that the mind can escape the body and the constraints of the physical world, is one facet of mind-wandering itself.

  Theory of mind

  Whether or not the mind is actually constrained by the mechanical functioning of the brain, we are actually very good at knowing what others are thinking, a talent known as ‘theory of mind’. There is no compelling reason to believe that this is due to non-material influences, such as entangled particles. It is partly intuitive, based on subtle cues we may not be aware of, but that are nonetheless received via the senses. It is partly due to cultural sharing. People of the same culture tend to respond in the same ways to the same situations—we tend to be embarrassed by the same social blunders, elated by the same victories, saddened by the same losses. And we share senses—we see what others see, hear what they hear, smell what they smell. We even share our mind-wanderings through storytelling, although that itself is a story for the next chapter. We also use simple observation to infer what’s going on in the minds of others.

  This is nicely illustrated by the Sally–Anne test, which is a test of children’s ability to infer that other people have a false belief about something. The child is shown a scene involving two dolls, Sally and Anne. Sally has a basket and Anne has a box. Sally puts a marble in her basket and leaves the scene. While Sally is away, naughty Anne takes the marble out of the basket and puts it in her box. Sally then comes back, and the child watching all this is asked where she will look for her marble. Children under the age of four typically say she will look in the box, which is where the marble actually is. Older children will understand that Sally did not see the marble being shifted, and will correctly say that Sally will look in the basket. They understand that Sally has a false belief. To that extent, at least, they know what’s in Sally’s mind, and that this is different from what’s in their own minds.

  Curiously enough, children younger than four seem to act as though they understand what others believe even if they can’t say so. In a remarkable Hungarian study, babies as young as seven months were influenced by the belief of another individual. The babies were shown movies of a ball that rolled behind a screen. The ball could then either stay behind the screen or roll away. The events were also watched by a cartoon character, who sometimes left the scene and came back. The position of the ball could be changed while the character was away, so he could believe the ball to be behind the screen when it wasn’t, or not behind the screen when it was. When the character returned and the screen was removed, the babies looked longer at the scene when the cartoon character’s expectation was not met. That is, they seemed to expect the cartoon character to be surprised, as though they could read his mind.

  This experiment suggests that an understanding of others’ beliefs can influence the way even young babies act, even if they can’t put words to that understanding. In the same study, adults were found to behave in very much the same way, with their actions influenced both by their own beliefs and those of another observer. The authors of this study write:

  The finding that others’ beliefs can be similarly accessible as our own beliefs might seem problematic for an individual, because it may make one’s behavior susceptible to others’ beliefs that do not reliably reflect the current state of affairs. However, the rapid availability of others’ beliefs might allow for efficient interactions in complex social groups. These powerful mechanisms for computing others’ beliefs might, therefore, be part of a core human-specific ‘social sense’, and one of the cognitive preconditions for the evolution of the uniquely elaborate social structure in humans.

  This social sense seems to be acquired at a very early age, and may even be inborn.

  To find out which parts of the brain are activated in mind-reading, people are placed in a brain scanner and told stories that allow them to deduce the beliefs of others. One story, for example, describes John telling Emily that he drives a Porsche, but his car is in fact a Ford. Emily knows nothing about cars, and so she believes that John’s car is a Porsche. Emily then sees the car, and the person in the scanner is asked what Emily thinks is the make of the car. Most people understand that Emily falsely believes it to be a Porsche. Understanding that others have false beliefs again activates the default-mode network, suggesting that mind-wandering can indeed take us into the minds of others.

  The understanding that others can have beliefs different from one’s own seems to be the most telling example of theory of mind. It is critical to social harmony, and allows us to correct mistaken beliefs in others—or at least try to do so. Emily, for example, might usefully be told that John is something of a liar, and shouldn’t be trusted. It can work both ways, though, since John might usefully, if cruelly, be told that Emily knows nothing about cars so he can create in her a false belief that is to his advantage—although probably only a temporary one. In a tolerant society, what is important may not be the understanding that other beliefs are false, so much as the understanding that people can have widely differing beliefs. Many, I am sure, will reject my belief that ESP does not exist, but understand that I hold that belief, and possibly feel sorry for me.

  Theory of mind has a recursive property, such that understandings can be embedded in understandings. I may believe that you believe that I believe in Santa Claus. Or I may believe that you feel sorry for me because you believe that I don’t believe in ESP. The psychologist David Premack takes it even deeper, suggesting: ‘Women think that men think that they think that men think that women’s orgasm is different.’ Well, he’s a mere
man, and it is he who thinks that, taking it deeper still. Runaway recursion may have been driven by the human propensity to deceive. If I know what you believe about me, I can then deceive you by acting contrary to that belief. This is well illustrated by the old Yiddish joke about a man who meets a business rival at a train station and asks where he is going. The business rival replies he is going to Minsk. The first man then says, ‘You’re telling me you’re going to Minsk because you want me to think you’re going to Pinsk. But I happen to know that you are going to Minsk, so why are you lying to me?’

  As the English poet and novelist Sir Walter Scott2 put it: ‘O what a tangled web we weave, / When first we practise to deceive!’

  People do vary, though, in the capacity to read minds. At one extreme is what has been termed ‘mind-blindness’, said to underlie the condition known as autism. One well-known case is a woman called Temple Grandin, who has a PhD in agricultural science and works at Colorado State University. Her autism doesn’t seem to have affected her intelligence, as she has written several books, three of them describing her own condition. Lacking a natural social understanding, she was forced to resort to detailed observations of people’s actual behaviour in order to figure out how to behave appropriately in social situations. The habit of close observation paid dividends, though, in her work on animal behaviour. The title of her most recent book is Animals in Translation: Using the Mysteries of Autism to Decode Animal Behavior, which prompted a BBC documentary unkindly entitled The Woman Who Thinks Like a Cow.