Swept up in the stream

As for his sister before him, bedtime for Isaac is a time for pondering the mysteries of consciousness. The other evening, Lizzie was settling him to sleep when, somewhat out of the blue, she quoted a line from The Gruffalo's Child, one of his favourite storybooks. Aha! Oho! Tracks in the snow! Whose are these tracks and where do they go? Nothing in particular had triggered this comment: there were no animal tracks on his orange duvet, and certainly no snow. It was just one of those thoughts that pop into your head for no particular reason, as thoughts do. Irrational they might seem, but unbidden, irrelevant thoughts such as these are occurrences with which, as adults, we are all perfectly familiar.

'Ah,' Isaac observed, 'so now you've got two things going round in your head!'

Baffled, Lizzie asked him to explain. Earlier, he reminded her, she had suddenly started singing the theme tune from a computer game they had been playing. When Isaac had asked her why, she had responded: 'Because it was going round in my head'. Isaac was simply recalling his mother's report of that earlier unbidden thought, and imagining it being joined in its lonely cranial revolutions by this new one.

What do children understand about where thoughts come from? As I noted in an earlier post, young children can get quite confused about the provenance of the contents of their minds. At times, they can give surprisingly materialistic explanations. Just before falling asleep one evening, Isaac mentioned the kids' spy drama MI High, of which his big sister is a fan. Lizzie asked him why he had suddenly started thinking of that. 'The thought was in my neck,' he replied, 'and then it just popped up into my head.' Perhaps he would give the same account of his mother's Gruffalo-themed musings. I envisage little thought pods lying dormant somewhere in the spinal column, and then hatching when local conditions are right, to flood the cortex with colour.

I'm not sure that we adults have much better theories about how thoughts can suddenly break into consciousness like this. One thing we can do, though, is look at what people understand about the controllability of their thoughts. In a series of studies, John Flavell and colleagues have asked this question of young children. One experimental procedure involves introducing children to a special chair called the 'No-Thinking' chair. When you are sitting in this chair, the child participant is told, you can make your thoughts stop altogether. Would you like to try? Recent studies show that, until at around age eight, children really do claim that their stream of consciousness ceases altogether when they are sitting in the chair. Slightly older children, in contrast, recognise that the tap of thoughts cannot simply get turned off. Ideas about mental uncontrollability seem to be very important later in life, in determining how adults respond to intrusive thoughts such as worries, obsessions, and possibly even hallucinations. Understanding the often chaotic flow that runs through our minds is, it seems, a process that gets started early in life.

Later, we ask Isaac whether he can stop these thoughts going round in his head. He sounds optimistic. 'Sometimes, like when I go to sleep, they stop, but when I wake up they start again. And after I've had my breakfast they really start!'

Building a dream baby

In a recent interview I was asked whether a background in developmental psychology was of any advantage when it came to working out the right and wrong ways to bring up children. 'Far from it,' was the gist of my reply. The Baby in the Mirror is not a parenting book, not least because I have no idea what makes a good parent. I know what makes an abusive one, or a loving one, and I have a pretty good idea about what kinds of stimulation of children's minds can be beneficial at different ages. But to suppose that knowledge of the science is a foundation for training perfect parents is, to my mind, a dangerous way to go. 

Nowhere is this demonstrated more effectively than in Christina Hardyment's wonderful Dream Babies: Childcare Advice from John Locke to Gina Ford. I read this book in its first, 1983 edition, and found myself wondering what Hardyment would have made of more recent attempts to construe parenting as a process that could be scientifically validated and enhanced. It was a pleasure, then, to see that the book was being reissued with additional material covering almost a quarter-century of new research. Hardyment's story starts with eighteenth-century attempts to turn Enlightenment ideas to use in child-rearing, guides us through a nineteenth-century fad for phrenology and the dawn of sustained scientific interest in developing minds, and concludes with a look at current oppositions between super-strict and ultra-liberal methods of baby control. By offering us such a broad historical sweep, Hardyment gracefully demonstrates how one generation's solemn orthodoxy becomes the next's flaky dogma. The long view points up the cycles and recurring patterns of thought on the subject, and inevitably makes us question how our own cherished beliefs about childcare will look from the perspective of the future. In her words, 'techniques of handling children have not made the steady progress towards improvement that some historians of childhood assert: they have always been tailored, sometimes attractively, sometimes unpleasantly, to suit the times.'

Of particular interest to me is Hardyment's tracing of the influence of certain key cognitive-developmental theorists. Alongside Freud, Hardyment rates the work of Jean Piaget as the greatest influence on the Spock-era baby manuals that held sway after the Second World War. As much as they were concerned with physical and moral development, parents were concerned that their charges should keep up intellectually, and Piaget had by far the most complete theory of cognitive development on offer. His views on the development of the object concept, for example, led to suggestions that object permanence could be trained by peekaboo games and other adventures in object occlusion. If intellectual development was a process, it was a process that could be speeded up. The flashcard parent was born. 

 

I have plenty of time for Piaget's theories, but translating them into childcare prescriptions misses the point of his claims about the logical ordering of certain cognitive advances. The developing brain requires stimulation, but it needs to be targeted (for a neuroscientifically sound attempt to sketch out what this might mean for parents, I recommend Lise Eliot's What's Going On In There? How the brain and mind develop in the first five years of life). Efforts to boost input beyond what is naturally available are likely to be fruitless, if not actually harmful. Science deals in generalities, while parents have to get to know particular children with their own particular combinations of personality traits and cognitive biases. There is also something profoundly unscientific in claiming that a certain technique for toilet-training or sleep control has 'worked', rather than having simply coincided with a developmental change which would have happened anyway. The truth is that the large-scale, scientifically rigorous studies that would prove the efficacy of such techniques have for the most part not been done, and may never be. All of this is a roundabout way of explaining why I was so concerned not to try to write a parenting manual. Such books often patronise parents, while playing on their anxieties about being seen to be active co-travellers in the miraculous journeys that their children are embarked on. If Athena and Isaac did turn out all right, it is not me who should be puffing up with pride.  

Call that art? Well, Daddy does

I have forgotten how to watch a 'grown-up' film. Sit me down in front of a street-raw depiction of urban alienation, say, or a sensitive charting of the emotional undercurrents that tug at the shell of a splintering family, and I will find myself asking, Where are the singing chipmunks? Why no intertextual references to classic fairytales? Is this movie really not interested in indoctrinating me into the moral values of the Disney/Pixar co-operative? Family life, and family viewing, have reduced me to a kind of dyslexia of the silver screen. I would once rush to watch Kieslowski or Todd Solondz; now I need things spelled out for me, preferably with plenty of acrobatic song-and-dance routines. If movies are texts, as the cultural studies pundits like to tell us, then I have forgotten how to read them. 

It doesn't help that I live in a part of the world that is poorly served by cinema. To catch a recent release, I have to trek to Gateshead's Metro Centre, where cinema seems to be less about watching films and more about talking, sleeping and eating pungent food in sociable darkness. Frustrating, because there is one film that has caught my eye but doesn't yet seemed to have found its way up north. Amir Bar-Lev's 'My Kid Could Paint That' tells the story of four-year-old Marla Olmstead, whose colourful paintings famously took the New York art world by storm. The story interests me for a couple of reasons. Firstly, it seems to be as much about the adults who are trying variously to protect and exploit Marla as it is about an ostensibly ordinary little girl. It touches on the question of whose interests are being served by bringing children's activities into the public eye in this way, and it reminds me that some of the side-effects of my own project—thrusting Athena, and to a certain extent Isaac, into the limelight—raise ethical questions which I cannot completely resolve. 

The other interesting thing about this film is that it asks whether children's creations can truly be described as artistic. Artists through the centuries have, of course, taken children's artworks seriously, both as inspiration for new works and as creations in their own right. Some of my favourite examples come from the work on children's crib speech, such as that produced by a two-year-old girl called Emily, studied by a group of psychologists and linguists in the 1980s. Many of Emily's bedtime monologues are startlingly beautiful. She uses self-directed language to replay significant events from the day that has just ended, and to plan ahead to what she will do and experience tomorrow. Reading little Emily's self-talk, and that of Anthony, another famous proponent of crib speech, makes us concur with the great linguist Roman Jakobson's judgement that such monologues are outstanding examples of infant art. 

In The Baby in the Mirror, I ask what Athena's various imaginative creations can tell us about the cognitive-developmental story behind children's art-making, as well as her wider understanding of the social functions of art. Much of the most interesting recent work in this respect has been conducted by Paul Bloom, whose excellent Descartes' Baby is partly concerned with what children's understanding of the art they produce and consume can tell us about humanity's broader relation to all things aesthetic. Particularly interesting is the way Bloom relates children's understanding of art to their ability to read the intentions of their social partners. Not only do you have to understand the creator's intention to depict a particular entity, but you also have to comprehend that the artist intended the result to be taken in a particular way: as a work of art, rather than as a factual document or an impertinence. In the chapter 'Lightning Ridge is Falling Down', I explore this two-level model of artistic intentions in relation to Athena's home movies, drawings, jokes and narrative songs. Perhaps of most interest to me is the question of whether, in these aesthetic experiments, Athena intends to represent her experience for herself. Does art have a personal function, for the maker, as well as a social function, for its audience? I would like to have said more in the book about the fascinating work of Peter van Sommers on this topic. Van Sommers found that adult participants in a psychological study would use private drawings for some of the same reasons that they use self-directed speech. People apparently use private artworks—doodles and scribbles, as well as more elaborate creations—to regulate their emotions and plan their behaviour, with no intention that the drawings will ever be seen by anyone but themselves. How much of professional (and amateur) artists' work has a similarly self-serving function? Is art really a gift to society (as Lewis Hyde has argued), or is it at least in part a treat for ourselves? 

It will be interesting to see how Marla's story fits in with this intention-reading account of children's artistic understanding. I suspect that she appreciates enough about the social functions of art to comprehend at least some of the fuss that has surrounded her. If anyone is planning a northern release for 'My Kid Could Paint That', they will have at least one guaranteed viewer. I may be slightly out of practice, but I'm sure that, if it has kids in it, I will understand most of what's going on. 

Why Johnny won't read

What do we have to do to persuade our children to read? If one Spanish politician gets his way, children in the small town of Noblejas will be paid by the hour just for reading books in their local library. The proposals have come about in response to a very high school drop-out rate in a predominantly agricultural (but not economically disadvantaged) area. Even in affluent British suburbs, schoolchildren's reading is being incentivized in various ways, such as the offering of sweet rewards for each book finished. If reading is meant to be a lifelong pleasure, why is it so hard to persuade children of the fact? 

This month sees the UK publication of a book by the American psychologist Maryanne Wolf which provides some answers to that puzzle. In Proust and the Squid: The Story and Science of the Reading Brain, Wolf draws on evolutionary and neuroscientific evidence in arguing that our brains were never really built for processing the printed word. Stretching back only ten thousand or so years into our past, reading is too recent an invention for us to have evolved any specific capacities for it. Caleb Crain's interesting essay in the New Yorker connects Wolf's arguments with our broader intuitions that, as a culture, we are reading less, and less willingly. Although our brains show remarkable flexibility in allowing us to cope with (and indeed excel at) this recent invention, perhaps, in the long run, we are simply giving in to nature.

The Baby in the Mirror is anything but a parenting book. I do not profess to know the right way to bring up a child; in a few cases I clearly demonstrate the wrong way. So I cannot take any credit for the fact that Athena reads avidly. She will take a book in the car with her and read it lurching around country lanes at speeds that would make either parent nauseous. She has always preferred to be reading for herself rather than having people doing it for her. In the chapter 'It's About a Little Mouse', I describe how she would 'read' books to herself before she had any clear idea about letter–sound correspondences, or even the correct order of turning pages. Long before she could decode text, she was imposing her own narrative structures on the information she encountered. She didn't learn about stories from books; she taught books about story. Children, like adults, use narrative to organize their experience and frame their memories. They have the basic understanding of how story works some time before they turn their attention to the printed word. 

Shared storybook sessions are important for young children, then, but perhaps not for all the reasons that parents think. For one thing, it is unlikely that sitting down with Mum and a book teaches young children much about the mechanics of reading. Whatever benefits follow from joint reading, enhanced understanding of how those squiggles on the page encode meaning is not one of them. In a recent study, French-Canadian four-year-olds read storybooks with a parent or teacher while their eye movements were recorded by a special headband fixed around the child’s forehead. Apparatus like this allows researchers to tell exactly where a child is looking: at the words on the page, where presumably the adult reader’s attention is focused, or at the illustrations. The eye-tracking data showed that children spent hardly any time looking at the text, even when it was embedded in the pictures in speech bubbles, or when it had distinctive features such as special decorations. Shared reading helps vocabulary development and story comprehension, but it doesn’t teach children anything about print or reading. That requires specific joint activities focused on decoding text, such as spelling out letters—something that can be done in a bookreading context, for sure, but only if letters, and not the story, are the focus.

Athena still enjoys the social element of being read to, even though she would rather be doing the reading herself. Perhaps she thinks that we adults don't do a particularly good job of it. Last night I asked her if we could do some reading together, and she said she would rather we told each other riddles. She came up with some good ones about suns and volcanoes (I put in a pretty good effort myself, I thought, with a riddle about a river). When it was time for lights-out, she begged me to tell her one more, so I promised that I would make one up overnight. Waking early, I typed and printed out an invention of my own so that it would be ready for her when she came down. (It is no Exeter Book marvel, but then it was six o'clock in the morning.) 

I can be very long, but I fit on any shelf.

You can get lost in me, but I am much smaller than you. 

I can take you to new places, but you will never have to leave your chair. 

What am I? 

She got it straightaway. 

All children are psychotic

Psychosis is a misunderstood term. Journalists are always confusing it with psychopathy, just as they often still insist that a 'schizophrenic' is someone with a Jekyll-and-Hyde-style split personality. (I could blame T. S. Eliot for this, but that would require another post.) In newspaper-speak, calling someone psychotic seems to mean that they are especially nasty and especially cold-hearted, in the mould of Saddam Hussein or Abu Musab Al-Zarqawi (I once saw both described thus, within a page of each other, in a British Sunday newspaper). If I were one of the large number of people who suffer in silence from a psychotic disorder, I would feel angry and more than a little betrayed. The irony is that psychosis found favour as a term among those many clinicians and researchers who were tired of the deep-rooted misconceptions about schizophrenia, and who now find that their preferred term has become as semantically garbled as its predecessor. 

In fact, psychosis refers to a group of psychiatric disorders which involve some disturbed relation to reality. The hallmarks of psychosis are symptoms like hallucinations (the perception of entities that are not actually present) and delusions (irrational, unshakeable beliefs about how things are). Among patients who receive a diagnosis of schizophrenia, one of the most common such symptoms is auditory verbal hallucinations, or hearing voices when no one is speaking. There is good evidence that these experiences are not confined to those with psychiatric diagnoses. Although voice-hearing can be a distressing, frightening and debilitating experience, several recent surveys have shown that a sizeable minority of healthy people hear voices and live with them quite comfortably. It may be entrenched in our cultural understanding as a first sign of madness, but voice-hearing is a phenomenon that affects people right across the spectrum of sanity and insanity.

It may also be an experience that is particularly prevalent in childhood. Last month saw the appearance of our article on children's susceptibility to imaginary verbal experiences, and the culmination of some research conducted over a number of years in Australia, the UK and the US. The roots of our work lay in some classic studies with adult psychiatric patients. In the 1970s, an experiment by Mintz and Alpert showed that voice-hearing schizophrenia patients (when compared to non-voice-hearing patients) produced especially vivid auditory imagery in the absence of any relevant stimulation. In the 1990s, Feelgood and Rantzen found a similar pattern among healthy adults who scored highly on a measure of susceptibility to hallucinations. Their experiment involved playing college students a recording of white noise and asking them whether they could hear any words being spoken. The students who were more prone to hallucinations were more likely to report having heard voices speaking amidst the noise. As described in his popular book on the psychology of psychosis, Madness Explained, Richard Bentall has suggested that voice-hearing happens because hearers have a difficulty in distinguishing between real and imagined events. Under certain circumstances, the individuals affected become tricked into believing that an experience, like a voice, that they have imagined has actually been perceived from the outside. 

This is a mistake that is particularly likely to occur in childhood. Young children have rich imaginative lives, but they also have a rather weak understanding of the boundary between reality and fantasy. Asking children to decide whether an experience is internally or externally generated may therefore be a tall order. We wondered whether one indicator of children's susceptibility to such confusions might be their reporting of imaginary companions. Dating at least as far back as Julian Jaynes' classic (and controversial) study of the origins of consciousness, several observers have noted that engaging with an imaginary playmate bears similarities with the experience of hallucinations. In a 2001 article, a team from the Isle of Wight found that children (aged 9–11) who admitted having had an imaginary companion were more likely to report hearing words in a recording of a human voice which had been treated so that the language was unintelligible. In our own study, we made some improvements to methodology and found the same results in two younger samples of children (ages 4–8). Children who reported having an imaginary friend were more likely to say that they heard words being spoken in a recording of jumbled-up, meaningless speech sounds, and this relation could not be accounted for by any obvious factors like age, gender or IQ. 

There are several reasons why children might be susceptible to confusing an imagined experience with a real one. Although kids often show a good understanding of the distinction between fantasy and reality, they can give out rather mixed signals when asked whether their imaginary friends are real or not. My niece, Annabel, had an imaginary friend called Mr Plate, who liked eating peas but was very badly behaved. When I asked her whether Mr Plate was real, she was indignant. Of course he was only pretend; how could I possibly think otherwise? And yet when I asked her whether I, a reality-rooted adult, would be able to meet and talk to Mr Plate, she promised that this could be arranged. I think we can get too caught up on the question of whether children know the difference between what is real and what is not real. Much more fruitful, in my view, is to ask what children understand about their own mental experience. In the strange world of childhood, what is internal is also external. Thoughts bleed into reality, as what is objectively real gradually takes up residence in the world of the mental. Drawing the boundary of one's individual mind, as a hermetically sealed entity that is unknowable to others, is a childhood's work.  

One issue is that young children have a rather weak understanding of how thinking operates. Indeed, they probably do not start to think, in the sense of experiencing a predominantly verbal stream of consciousness, until they have had a chance to internalize the linguistic social dialogues that are going on around them. In Chapter 8 of The Baby in the Mirror, I look at the work of the great Soviet psychologist, L. S. Vygotsky, whose writings have transformed our understanding of how thinking develops in childhood. Vygotsky argued that the ongoing internal conversation we call 'thinking' develops when the child's social interactions become reconstructed internally, in their own private experience. The implications of this theory, such as that our thinking has the quality of a dialogue with ourselves, are profound. But one simple implication is that inner speech arrives in children's heads at a certain point in development, and therefore, for a time, will seem unfamiliar. It is possible that young children have these experiences of hearing internal voices engaging with each other in the dialogue of thought, but simply do not recognise them as thinking. Instead, they may attribute them to some external agency, such as an imaginary friend. 

This still leaves us with a paradox. Psychologists such as Marjorie Taylor and Stephanie Carlson have argued, on the basis of their own careful empirical studies, that engaging with imaginary companions is generally a 'good thing' for children's development. Some studies, for example, have shown that children with imaginary companions do better at tasks measuring social understanding and creativity. And yet our view of imaginary companions seems to depict such children as having a weaker grasp of how thinking works. The solution to the paradox may lie in the unexamined assumption that what may be a cause for concern in adulthood must also ring alarm bells when it occurs in childhood. A child's mind must be a strange place to be. Trying to project oneself imaginatively into these unfamiliar spheres of existence is exhilarating, but not always straightforward. 

I don't say much about imaginary companions in the book, because it covers a developmental period when pretend friends are not really yet in evidence. In fact, Athena's friends have been almost exclusively real ones. Her brother is much more of a fantasist. Isaac doesn't yet have a distinct, named imaginary companion, but he is always telling us about his 'other house', where there are pet lions and reindeer and pigs that keep breaking into the kitchen and making a terrible mess on the floor. 'Is your other house real,' I ask him, 'or only pretend?' He is adamant that it is as real as this one is. I ask him whether I might be able to go to his other house one day, and he says yes, although—and I detect a subtle attempt to protect his fantasy—it is a long way away and I would probably fall asleep on the way. 

So: all children are psychotic. There is some truth in the statement, if we accept that experiences that can be abnormal in adulthood can be perfectly typical in childhood. Young children's experiences have some similarities with the unusual perceptions and beliefs that both healthy adults and psychiatric patients report, and they may also share some common underlying cognitive mechanisms. One thing that's certain is that we need to use the term 'psychosis' properly, and concentrate on the specific experiences that we want it to refer to. If we are careful to do that, understanding the strange world of the young child could have benefits that extend far beyond the playground. 

(With apologies to Douglas Coupland for the title.)

Waiting for Mr Claus

With a fender-bending crash, Lightning McQueen scores a victory against his old adversary, the battered NYPD patrol car that has been setting land-speed records up and down our hallway. The toy-trashing ceases momentarily, then Isaac's voice calls from the other room. 

'How does Father Christmas get down the chimney?'

'He has to squeeze in really tight.' 

'But his tummy's too big.'

I feel a white lie turning into a black one. 'He can just about make himself small enough to fit down a chimney.'

'But how?'

'You know, like when you're trying to squeeze into a narrow space and you pull your tummy in.'

I'm not trying to fend off a child's creeping doubt, not yet. Unlike his older sister, who now accepts talk of Father Christmas with the shrugging tolerance of someone who knows she is being spun a yarn, Isaac still subscribes willingly to the Santa Claus story. In The Baby in the Mirror, I suggested that the toddler Athena's willingness to enter into pretence scenarios foretold her eager self-immersion in the imaginary storyworlds of middle childhood. When you are pretending, you follow the rules of the world you have created, no matter how far-fetched they might be. But you don't lose sight of the fact that that world is invented; you keep one foot in the real world, even when the imaginary action is at its height. 

Many developmental psychologists, such as Jacqueline Woolley and Paul Harris, would argue that children deal with these made-up contexts pretty much as adults do. Kids are not fundamentally confused about the distinction between fantasy and reality, any more than adults are immune to such boundary-blurrings. And yet Santa Claus, and other fantastical entities like the Tooth Fairy, may present us with a special case. Isaac knows that the old man we saw at Alnwick Gardens yesterday, who sat in his grotto dishing out presents supplied by an elf with a walkie-talkie, was not the genuine article. He knows that there is a realer version out there, planning his visit in the dead of Monday night. Given that he will see no other evidence of that visitor than a chewed carrot and an empty sherry glass (and maybe, if he's good, a well-stuffed stocking), it is perhaps surprising that his belief in the bearded one is so strong. My own white or off-white lies probably make little difference in this regard. In one study, children's strength of belief in such figures hardly correlated with parental encouragement of those beliefs. Isaac would probably have come to buy in to the Santa myth anyway, with or without the efforts we have made to make him seem real. 

Perhaps this explains Isaac's concerns about the practicalities of Mr Claus' arrival. He is not trying to point out logical flaws in the Father Christmas story, so much as fit a fact that he is already pretty certain about (Santa's existence) into his existing understanding of the world. He is more concerned with the logic of how that story can happen than with the bigger metaphysical picture. Santa is a flesh-and-blood person of certain fixed dimensions, who has to worry about squeezing through narrow spaces just as any other rooftop-travelling geriatric would have to do. In time—perhaps when he is better able to think through the practicalities of single-handedly performing several billion overnight deliveries—Isaac will probably imbue Santa with supernatural powers to go with his purely physical accomplishments. As with other metaphysical matters, children look heavenwards for explanations when physical ones fail to suffice. Jingling his bells, Santa will attain the powers of a god, just before he vanishes from Isaac's life for ever. 

Parking sensors

He’s a boy, therefore he needs a train set. Brio looked pricey, so I bought him a Tesco version for less than a tenner. He is on the living room carpet, fitting the toggle end of one carved piece of softwood into the slot of another. His faintly downed upper lip is beaked in concentration. At his back is a civil engineer’s dream of a bridge system: two Sydney Harbours flanking a Humber. The train’s magnetic links have been connected, the red oil tanks loaded. As he turns to gather a final piece of cargo, his feet cantilever into the bridges, flattening them. ‘Uh-oh.’ He sets off to inspect the damage, trampling right across the track he has just laid. I suggest he get up and walk around the model to the bit that requires attention, but his needs lead him in a straight line: making a detour to reach the thing he wants will require a little more self-discipline. 

Since the wobbly days of babyhood Isaac has developed amazing motor control—he can pick things out of his bath that I can’t even see—but the body that makes it possible remains a mystery to him. It exists, as physical and permanent as anything in his toy box, but he has a hard time making allowances for it. Without an awareness of how big it is, and how heavy, it wreaks destruction as quickly as it puts things together. Like his sister before him, his idea of playing hide-and-seek is to stand in the corner and cover his eyes. ‘Watch that body of yours,’ I want to tell him. ‘There’s more to you than you think.' 

Awareness of our own bodies seems a relatively recent evolutionary achievement. At the University of Louisiana–Lafayette, Daniel Povinelli has been investigating how only some species of apes (chimps, orangutans and humans, but not gorillas) can recognise their own appearance in mirrors. He argues that our awareness of ourselves as physical entities stems from our common ancestry in the trees. To plan their passage through the canopy (and, in particular, to avoid being dumped on the ground by less sturdy branches), arboreal species need to be able to factor their own weight into their calculations. Land-lovers like gorillas can get by without any such sophistication. For Povinelli, this is a clue to why only some species of apes show mirror self-recognition. Learning the lesson of yourself, it seems, requires some hard bumps in your evolutionary past. 

Mirror self-recognition is usually tested with a simple task. A blob of rouge is applied surreptitiously to the participant’s face, and the observers wait to see whether, when confronted with their own image in a mirror, the chimp, gorilla or human infant will attempt to remove it. Toddlers typically pass the rouge test at around eighteen months. To test whether this translates into a practical awareness of one’s own physicality, Chris Moore and his colleagues at Dalhousie University present toddlers with a supermarket trolley rigged up with a blanket attached to the handle. In order to reach the handle to push the trolley, the toddler has to stand on the blanket. The results can be comical. The little volunteers know how the trolley works—nothing satisfies a toddler so much as pushing a trolley—but it takes time for them to realise that their own bodies are impeding its movement, and devise strategies such as kicking the blanket out of the way. 

The jury is still out on whether toddlers fail this task because of a general problem in understanding the physics of weight and obstruction, or because they specifically fail to see their own bodies as the obstacle. Isaac still crawls under tables to retrieve something and then stands up straight and clunks his head on the underside. Perhaps he needs parking sensors, or at least a little more experience of how much of him there is. Getting used to the vehicle he gets around in is, like many things, going to be a matter of time.