On perception and learning.

On perception and learning.

Cuddly.

Fearful.

Monstrous.

Peering with the unwavering focus of a watchful overlord.

A cat could seem to be many different things, and Brendan Wenzel’s recent picture book They All Saw a Cat conveys these vagrancies of perception beautifully. Though we share the world, we all see and hear and taste it differently. Each creature’s mind filters a torrential influx of information into manageable experience; we all filter the world differently.

They All Saw a Cat ends with a composite image. We see the various components that were focused on by each of the other animals, amalgamated into something approaching “cat-ness.” A human child noticed the cat’s soft fur, a mouse noticed its sharp claws, a fox noticed its swift speed, a bird noticed that it can’t fly.

All these properties are essential descriptors, but so much is blurred away by our minds. When I look at a domesticated cat, I tend to forget about the sharp claws and teeth. I certainly don’t remark on its lack of flight – being landbound myself, this seems perfectly ordinary to me. To be ensnared by gravity only seems strange from the perspective of a bird.

theyallsawThere is another way of developing the concept of “cat-ness,” though. Instead of compiling many creatures’ perceptions of a single cat, we could consider a single perceptive entity’s response to many specimens. How, for instance, do our brains learn to recognize cats?

When a friend (who teaches upper-level philosophy) and I were talking about Ludwig Wittgenstein’s Philosophical Investigations, I mentioned that I felt many of the aims of that book could be accomplished with a description of principal component analysis paired with Gideon Lewis-Kraus’s lovely New York Times Magazine article on Google Translate.

My friend looked at me with a mix of puzzlement and pity and said, “No.” Then added, as regards Philosophical Investigations, “You read it too fast.”

wittgensteinOne of Wittgenstein’s aims is to show how humans can learn to use language… which is complicated by the fact that, in my friend’s words, “Any group of objects will share more than one commonality.” He posits that no matter how many red objects you point to, they’ll always share properties other than red-ness in common.

Or cats… when you’re teaching a child how to speak and point out many cats, will they have properties other than cat-ness in common?

In some ways, I agree. After all, I think the boundaries between species are porous. I don’t think there is a set of rules that could be used to determine whether a creature qualifies for personhood, so it’d be a bit silly if I also claimed that cat-ness could be clearly defined.

But when I point and say “That’s a cat!”, chances are that you’ll think so too. Even if no one had ever taught us what cats are, most people in the United States have seen enough of them to think “All those furry, four-legged, swivel-tailed, pointy-eared, pouncing things were probably the same type of creature!”

Even a computer can pick out these commonalities. When we learn about the world, we have a huge quantity of sensory data to draw upon – cats make those noises, they look like that when they find a sunny patch of grass to lie in, they look like that when they don’t want me to pet them – but a computer can learn to identify cat-ness using nothing more than grainy stills from Youtube.

Quoc Le et al. fed a few million images from Youtube videos to a computer algorithm that was searching for commonalities between the pictures. Even though the algorithm was given no hints as to the nature of the videos, it learned that many shared an emphasis on oblong shapes with triangles on top… cat faces. Indeed, when Le et al. made a visualization of the patterns that were causing their algorithm to cluster these particular videos together, we can recognize a cat in that blur of pixels.

The computer learns in a way vaguely analogous to the formation of social cliques in a middle school cafeteria. Each kid is a beautiful and unique snowflake, sure, but there are certain properties that cause them to cluster together: the sporty ones, the bookish ones, the D&D kids. For a neural network, each individual is only distinguished by voting “yes” or “no,” but you can cluster the individuals who tend to vote “yes” at the same time. For a small grid of black and white pixels, some individuals will be assigned to the pixels and vote “yes” only when their pixels are white… but others will watch the votes of those first responders and vote “yes” if they see a long line of “yes” votes in the top quadrants, perhaps… and others could watch those votes, allowing for layers upon layers of complexity in analysis.

three-body-problem-by-cixin-liu-616x975And I should mention that I feel indebted to Liu Cixin’s sci-fi novel The Three-Body Problem for thinking to humanize a computer algorithm this way. Liu includes a lovely description of a human motherboard, with triads of trained soldiers hoisting red or green flags forming each logic gate.

In the end, the algorithm developed by Le et al. clustered only 75% of the frames from Youtube cat videos together – it could recognize many of these as being somehow similar, but it was worse at identifying cat-ness than the average human child. But it’s pretty easy to realize why: after all, Le et al. titled their paper “Building high-level features using large scale unsupervised learning.”

Proceedings of the International Conference on Machine Learning 2010
You might have to squint, but there’s a cat here. Or so says their algorithm.

When Wittgenstein writes about someone watching builders – one person calls out “Slab!”, the other brings a large flat rock – he is also considering unsupervised learning. And so it is easy for Wittgenstein to imagine that the watcher, even after exclaiming “Now I’ve got it!”, could be stymied by a situation that went beyond the training.

Many human cultures have utilized unsupervised learning as a major component of childrearing – kids are expected to watch their elders and puzzle out on their own how to do everything in life – but this potential inflexibility that Wittgenstein alludes to underlies David Lancy’s advice in The Anthropology of Childhood that children will fair best in our modern world when they have someone guiding their education and development.

Unsupervised learning may be sufficient to prepare children for life in an agrarian village. Unsupervised learning is sufficient for chimpanzees learning how to crack nuts. And unsupervised learning is sufficient to for a computer to develop an idea about what cats are.

But the best human learning employs the scientific method – purposefully seeking out “no.”

I assume most children reflexively follow the scientific method – my daughter started shortly after her first birthday. I was teaching her about animals, and we started with dogs. At first, she pointed primarily to creatures that looked like her Uncle Max. Big, brown, four-legged, slobbery.

IMG_5319.JPG
Good dog.

Eventually she started pointing to creatures that looked slightly different: white dogs, black dogs, small dogs, quiet dogs. And then the scientific method kicked in.

She’d point to a non-dog, emphatically claiming it to be a dog as well. And then I’d explain why her choice wasn’t a dog. What features cause an object to be excluded from the set of correct answers?

Eventually she caught on.

Many adults, sadly, are worse at this style of thinking than children. As we grow, it becomes more pressing to seem competent. We adults want our guesses to be right – we want to hear yes all the time – which makes it harder to learn.

The New York Times recently presented a clever demonstration of this. They showed a series of numbers that follow a rule, let readers type in new numbers to see if their guesses also followed the rule, and asked for readers to describe what the rule was.

A scientist would approach this type of puzzle by guessing a rule and then plugging in numbers that don’t follow it – nothing is ever really proven in science, but we validate theories by designing experiments that should tell us “no” if our theory is wrong. Only theories that all “falsifiable” fall under the purvey of science. And the best fields of science devote considerable resources to seeking out opportunities to prove ourselves wrong.

But many adults, wanting to seem smart all the time, fear mistakes. When that New York Times puzzle was made public, 80% of readers proposed a rule without ever hearing that a set of numbers didn’t follow it.

Wittgenstein’s watcher can’t really learn what “Slab!” means until perversely hauling over some other type of rock and being told, “no.”

We adults can’t fix the world until we learn from children that it’s okay to look ignorant sometimes. It’s okay to be wrong – just say “sorry” and “I’ll try to do better next time.”

Otherwise we’re stuck digging in our heels and arguing for things we should know to be ridiculous.

It doesn’t hurt so bad. Watch: nope, that one’s not a cat.

16785014164_0b8a71b191_z
Photo by John Mason on Flickr.

On David Lancy’s The Anthropology of Childhood, and violence against women (again!), and proscriptive parenting advice.

On David Lancy’s The Anthropology of Childhood, and violence against women (again!), and proscriptive parenting advice.

Despite being my family’s primary daytime parent, I’ve read extremely few parenting guides.  Zero, as it happens, unless you count Everywhere Babies (if you’re interested, here is a previous post where I discussed this baby-wrangling treasure) or Far from the Tree.

51E2pM00dFLPersonally, I count Andrew Solomon’s Far from the Tree as a parenting guide.  I was very nervous about the prospect of having a kid.  I worried that I’d be a rubbish parent.  I worried that I’d have an unmanageable kid.  Then I read Far from the Tree, and I stopped worrying.  K & I decided to forgo prenatal genetic testing; Solomon had convinced me that we could love whomever we received.  And he taught me the one essential lesson I needed to set me on my journey to becoming at least a tolerable (I hope!) parent: relax.

I’d recommend that any parent-to-be (or parent, or person, honestly … it’s a lovely book) read Far from the Tree.  But for the moment, here’s my favorite passage from the book, one that both stresses the importance of accepting what happens and accepting people, including your own children, for who they are:

People of higher socioeconomic status tend toward perfectionism and have a harder time living with perceived defects.  One French study said baldly, “The lower classes show a higher tolerance for severely handicapped children.”  An American study bears out that conclusion, inasmuch as higher-income families are “more apt to stress independence and self-development,” while lower-income families emphasize “interdependence among family members.”  Better-educated more-affluent families are more likely to seek placement for their children, and white families do so more often than minority families, though disturbingly high numbers of minority parents lose children to foster care.  I did back-to-back interviews with a white woman who had a low-functioning autistic son, and an impoverished African-American woman whose autistic son had many of the same symptoms.  The more privileged woman had spent years futilely trying to make her son better.  The less advantaged woman never thought she could make her son better because she’d never been able to make her own life better, and she was not afflicted with feelings of failure.  The first woman found it extremely difficult to deal with her son.  “He breaks everything,” she said unhappily.  The other woman had a relatively happy life with her son.  “Whatever could be broken got broken a long time ago,” she said.  Fixing is the illness model; acceptance is the identity model; which way any family goes reflects their assumptions and resources.

A child may interpret even well-intentioned efforts to fix him as sinister.  Jim Sinclair, an intersex autistic person, wrote “When parents say, ‘I wish my child did not have autism,’ what they’re really saying is, ‘I wish the autistic child I have did not exist, and I had a different (non-autistic) child instead.’  Read that again.  This is what we hear when you mourn over our existence.  This is what we hear when you pray for a cure.  This is what we know, when you tell us of your fondest hopes and dreams for us: that your greatest wish is that one day we will cease to be, and strangers you can love will move in behind our faces.”

Once I had Solomon’s advice in hand (& re-typed & ready to share with you, dear reader!), why would I bother reading another parenting guide?  Any time I come to a situation that Solomon didn’t address, I simply close my eyes and imagine what a cave person attempting to raise a daughter to participate in our technologically-magical information-based economy would do.  Most of the time that imagined cave person (me, in fact) would simply feel perplexed (you’re telling me that your telephone is also a camera??), but sometimes cave dad would probably coo & pat his daughter’s belly, or else read her another book.

I love learning, though.  If I had access to a good book on parenting, I’d read it!  I simply assumed that I wouldn’t like most of the ones I could find at the bookstore.

onlybabybookThat’s why I was so excited when I read Michael Erand’s New York Times article earlier this year, titled “The Only Baby Book You’ll Ever Need.”  Here, let me quote a few lines from the introduction:

Professor Lancy, who teaches at Utah State University, has pored over the anthropology literature to collect insights from a range of culture types, along with primate studies, history and his own fieldwork in seven countries.  He’s not explicitly writing for parents.  Yet through factoids and analysis, he demonstrates something that American parents desperately need to hear: Children are raised in all sorts of ways, and they all turn out just fine.

That sounds exactly like what I’d enjoy reading!  A book about parenting that’s descriptive, not proscriptive.  And I’ve loved reading pop anthropology books ever since paying a quarter for a lovely hardcover edition of Desmond Morris’s The Naked Ape at a library book sale in Evanston, Illinois.

CaptureI have to assume that the first edition of the recommended book, David Lancy’s The Anthropology of Childhood: Cherubs, Chattel, Changelingswas very different from the current second edition, which was published in February of this year.  Because the book I read was intensely proscriptive.  Yes, Lancy documents a wide variety of parenting strategies.  But he also makes abundantly clear his opinion that those parenting strategies would not be appropriate in our culture.

I didn’t mind.  Lancy’s book is quite good, and his ideas about what makes good parenting align closely with my own.  But someone who’d read the Times article might expect the book to be very different from what it is.

As with Dorothy Dinnerstein’s The Mermaid and the Minotaur (would you count a work of feminist philosophy as a parenting guide?  If so, perhaps I’d read one after all.  My previous post about Dinnerstein’s book and parenting is here), Lancy’s foremost prescription is equality — most conspicuously, since not all cultures have multiple races, castes, or tiers of wealth, he’s referring to gender equality:

There is a world in which children almost always feel “wanted” and where “there is no cultural preference for babies of either sex.”  Infants are suckled on demand by their mothers and by other women in her absence.  They are indulged and cosseted by their fathers, grandparents, and siblings.  Children wean themselves over a long period and are given nutritious foods.  They are subject to little or no restraint or coercion.  Infants and toddlers are carried on long journeys and comforted when distressed.  If they die in infancy, they may be mourned.  They are rarely or never physically punished or even scolded.  They are not expected to make a significant contribution to the household economy and are free to play until the mid to late teens.  Their experience of adolescence is relatively stress free.  This paradise exists among a globally dispersed group of isolated societies — all of which depend heavily on foraging for their subsistence.  They are also characterized by relatively egalitarian and close social relations, including relative parity between men and women.**

  ** Thinking of Malinowki’s ethnography of the Trobriand Islanders, I’m tempted to argue that any society with conspicuous gender parity is likely to be a paradise for children.

And shortly thereafter, Lancy makes explicit that many of the parenting practices he’s documenting are horrible.  For instance, misogyny is rampant throughout the world, to such an extent that a significant fraction of female children are never even born.  This is rotten, & if enough parents choose to do this they’re even dooming their own (male, presumed heterosexual) children.  There parallels between this behavior and choosing not to vaccinate a child with a healthy immune system — in both cases, children are doomed if all parents make the same selfish choice, either because there won’t be enough women for the next generation to form families, or because the herd immunity relied upon to protect freeloaders will be lost.

Both China & India, where sex-selection of unborn children is rampant, are attempting legislative correctives.  In China, they’ve outlawed the practice, and in India they’ve instituted monetary incentives for female progeny… although that is conceptually problematic as well.  Here’s Jean Dreze & Amartya Sen from their book An Uncertain Glory:

j10175To illustrate, consider the recent introduction, in many Indian states, of schemes of cash incentives to curb sex-selective abortion.  The schemes typically involve cash rewards for the registered birth of a girl child, and further rewards if the girl is vaccinated, sent to school, and so on, as she gets older.  These schemes can undoubtedly tilt economic incentives in favour of girl children.  But a cash reward for the birth of a girl could also reinforce people’s tendency to think about family planning in economic terms, and also their perception, in the economic calculus of family planning, that girls are a burden (for which cash rewards are supposed to compensate).  Further, cash rewards are likely to affect people’s non-economic motives.  For instance, they could reduce the social stigma attached to sex-selective abortion, by making it look like some sort of ‘fair deal’ — no girl, no cash.  The fact that the cash incentives are typically lower for a second girl child, and nil for higher-order births, also sends confusing signals.  In short, it is not quite clear what sort of message these cash incentives are supposed to convey about the status and value of the girl child, and how they are supposed to affect social attitudes towards sex-selective abortion.  As mentioned earlier, the workings of social norms is critically important in this kind of area of values and actions, and it is important to think about the possible effects of cash transfers on social norms and their role, and not just about economic self-interest.

Paying parents for their misfortune of raising a girl still perpetuates misogyny.  And setting minimum standards on her care (you receive money if she’s vaccinated, if she attends school) likely results in that bare minimum being given.

And now, let me get back to Lancy’s horror:

More commonly, we find that the infant’s sex is highly salient in determining its fate.  Some years ago, I came across a United Nations report, on the cover of which was a picture of a mother holding on her lap a boy and a girl of about the same age, possibly twins.  The girl was skeletal, obviously in an advanced state of malnutrition, the boy robust and healthy.  He sat erect, eyes intent on the camera; she sprawled, like a rag doll, her eyes staring into space.  That picture and what it represented has haunted me ever since.

That’s not a value-less scientific description.  Which is fine.  I’m happy that Lancy’s book (the current edition, at least) is proscriptive.  Because Erand’s article, which included lines such as, “The book does not render judgments, like other parenting books we know,” also mentioned tidbits like, “In Gapun, an isolated village in Papua New Guinea, children are encouraged to hit dogs and chickens, and to raise knives at siblings.

Really?  David Lancy doesn’t judge parents who give their children unsupervised access to knives?

Oh, wait.  He does.  He thinks that letting kids play with knives is bad.  From The Anthropology of Childhood:

On Vanatinai Island in the South Pacific, “children … manipulate firebrands and sharp knives without remonstrance … one four year old girl had accidentally amputated parts of several fingers on her right hand by playing with a bush knife.”

And, later, Lancy is even more explicit.  Yes, different cultures use different parenting strategies.  To prepare a child for relatively simple life in an agrarian village — especially if you give birth to eight children and will be happy if only four of them survive — it’s fine to ignore them and expect them to learn what they need to know by watching their elders.  But attempting equivalent parenting strategies in our culture would, in Lancy’s opinion, invite disaster:

At the outset of this chapter, I set up a juxtaposition.  One view holds that, to succeed in life, children require the near-full-time attention of a mother who treats childrearing as a vocation and prepares herself assiduously.  A contrary view is that this is a task best shared among a variety of individuals, a village.  What can we conclude?  I would argue that, to prepare a child for life in the village, it is neither necessary nor an efficient use of scarce resources to put the burden on any one individual.  However, to prepare a child for the modern world, spreading the responsibility among a variety of individuals — none of whom is in charge — invites disaster.  Hillary Clinton, in It Takes a Village, tries to apply the village model to the modern situation.  She argues for improvements in schools and social service agencies, an increase in library and playground facilities, and after-school programs — among other things.  All these proposals are helpful, but all these agents — teachers, librarians, playground supervisors, Boys & Girls Club volunteers — cannot, collectively, substitute for a dedicated, resourceful parent.  They are not related to the child and, in our society, the village is not responsible.  The parent is.  At best, these agents can only assist the parent in fulfilling their plan for the child.

Having said that much, I want immediately to disavow any claim that this task requires the full-time ministrations of the child’s biological mother.  There is overwhelming evidence — not reviewed here — that fathers, adoptive parents, lesbian partners of the biological mothers, and grandparents can all do a fine job.  Any of them, or the child’s mother, can and usually do avail themselves of an array of supplementary caretakers.  A working mother, in particular, may well bring home cultural, intellectual, and, certainly, economic resources that a non-working mother cannot provide.

So parenting in contemporary society is at least somewhat like physics, as it is tough to insure the child’s future success and a close, lasting filial relationship.  But, ultimately, we come full circle in that, as long as a reasonably competent and caring individual is in charge, the more loving, intelligent, and dedicated helpers surrounding the nest, the better off the twenty-first-century child will be.

Lancy writes that those village children’s lives are often bad, and that imported practices from Western nations have made them even worse:

Numerous studies have shown the deleterious effects on children’s health in the agriculturalist’s pursuit of the “production” strategy.  However, as the land is brought fully into cultivation, population-limiting mechanisms (such as the post-partum sex taboo) should develop to curtail further growth.  And this seems to have happened in many, many cases.  However, Western influence in the past hundred years seems to have dismantled these mechanisms, including, especially, abortion and infanticide.  Improved nutrition and healthcare for mothers has no doubt brought benefits.  But missionary efforts to stamp out “pagan” practices like polygyny also undermined the post-partum taboo on intercourse, even while they simultaneously blocked the introduction of modern contraceptives.  Additionally, “fashion” and commercial interests pushing infant “formula” have drastically reduced the number of infants being breastfed [breastfeeding is often an effective contraceptive.  Also, my computer marks “breastfed” and “breastfeeding” as spelling errors.  Yeah paternalistic misogyny!].  The result has been, in many parts of the world, population growth outstripping opportunities for either employment or improved food production.

Lancy even ends The Anthropology of Childhood with a powerful statement about economic & medical ethics.  Indeed, it’s difficult to read this as being anything but proscriptive:

Even though we recoil from discussions of children as chattel, our current policies, in fact, turn children into commodities with a precise dollar value.  Effectively, we embrace the notions that anyone can have a child, everyone can have as many children as they want, infertility can be circumvented, and the fetus is human and deserves whatever measures are available to keep it alive, regardless of any handicaps or defects it may harbor.  The net result of our mindset is that the marketplace decides the fate of children.  In poor countries, food shortages mean many potentially sound children will suffer malnutrition and neglect.  Wealth in the “North” that might be sent “South” to vaccinate, educate, and feed these children is, instead, spent at home on expensive technologies and caretakers to keep alive children whose quality of life is non-existent.  While sick, premature babies born to the well-off will survive through “miracles” of modern medicine, the poor will lose their otherwise healthy children to preventable diseases.

To me, this is a sensible proscription to make — it is similar to my own reasoning for abandoning a career in biomedical research.  Medical spending will continue to spiral out of control if we focus on preserving life at all costs with no concern for quality of life, and by wasting that money we perpetuate egregious harm through economic hardship.

So, I was thrilled to read David Lancy’s book.  I assume you’d like it too, given that you still seem to be reading my post about it.

Just, don’t go into it expecting a descriptive work devoid of value claims.  Because that’s not what you’re getting, at least not if you read the current edition.

And I’m still trying to figure out why Erand had such a different impression.  Because, sure, it’s possible that the first edition was extremely different.  But I think the confusion is more likely related to a point I made at the beginning of this essay: when I imagine myself as a cave person trying to raise his daughter, I have to imagine that cave dad raising his daughter for our world.  Not his world.

It’s a common mistake when people discuss human evolution.  Like, paleo diets?  Seems like a reasonable idea, trying to eat what humans evolved to eat.  But humans also evolved for constant motion & early death.  If that’s the way you’re planning to live, then, sure, you’ve got a valid argument for eating that way.  If not, the argument seems much less compelling.

Here’s where the problem comes from in Erand’s piece.  He writes:

caIn the ‘pick when ripe’ culture, babies and toddlers are largely ignored by adults, and may not be named until they’re weaned.  They undergo what he calls a ‘village curriculum’: running errands, delivering messages and doing small-scale versions of adult tasks.  Only later are they ‘picked,’ or fully recognized as individuals.  In contrast, in ‘pick when green’ cultures, including our own, it’s never too early to socialize babies or recognize their personhood.

But, Lancy makes clear why “pick when ripe” cultures made the choices they did.  As in, huge infant mortality meant that high-investment parenting would probably be wasted: why should that parent care that a kid was on track for greatness if the kid then dies at three?  And the potential “greatness” that was perceived to be within reach was pretty meager anyway — even a neglected child could eventually catch up and learn to farm well enough.

Whereas a parent who expects his or her children to survive, and who will only attempt to raise one to three (instead of seven to ten, with 60% of them dying young), should invest a lot of time.  Especially if you’re hoping for some complex, modern version of “success,” something involving happiness, for instance, and money.

And, yes, Lancy also thinks you should teach your children to do chores.

On attempts to see the world through other eyes.

On attempts to see the world through other eyes.

flowers

Most writers spend a lot of time thinking about how others see the world.  Hopefully most non-writers spend time thinking about this too.  It’s easier to feel empathy for the plights of others if you imagine seeing through their eyes.

So I thought it was pretty cool that the New York Times published an article about processing images to represent how they might appear to other species.

The algorithm shifts the color distribution of images to highlight which objects appear most distinct for an animal with different photoreceptors.  I thought it was cool even though the processing they describe fails in many ways to convey how differently various animals perceive the world.

For one thing, image processing can only affect visuals.  Another species may rely more on sound, scent, taste (although perhaps it’s cheating to list both scent and taste — they are essentially the same sense, chemodetection, with the difference being that humans respond more sensitively, and to a wider variety of chemicals, with our noses than our tongues), touch, sensing magnetic fields, etc.

If we assume that other animals will also place maximal trust in the detection of inbound electromagnetic radiation from the narrow band we’ve deemed “the visual spectrum,” we can fool ourselves regarding their most likely interpretations.  For an example, you could read my previous post about why rattlesnakes might assume that humans employ chameleon-like camouflage (underlying idea courtesy of Jesus Rivas & Gordon Burghardt).

The second problem with assuming that an image with shifted colors represents how another animal would view the world is on the level of neurological processing.  When a neurotypical human looks at an image and something resembles a face, that portion of the image will immediately dominate the viewer’s attention; a huge amount of human brainpower is devoted to processing faces.  Similarly, some dogs, if another dog enters their visual field, have trouble seeing anything else.  And bees: yes, they see more blues & ultraviolets than we do, but it’s also likely that flowers dominate their attention. I imagine it’s something like the image below, taken with N and her Uncle Max on a recent walk. Although, depending on your personality, you might have some dog-style neurological processing, too.

unnamed

Even amongst humans this type of perceptual difference exists.  A friend of mine who does construction (ranked the second-best apprentice pipefitter in the nation the year he finished his training, despite being out at a buddy’s bachelor party, i.e. not sleeping, all night before the competition), when he walks into a room, immediately notices all exposed ductwork, piping, etc.  Most people care so little about these features as to render them effectively invisible.  And I, after three weeks of frantic itching and a full course of methylprednisolone, could glance at any landscape in northern California and immediately point out all the poison oak.  My daughter can spot a picture or statue of an owl from disconcertingly far away and won’t stop yelling “owww woo!” until I see it too.

The color processing written up in the New York Times, though, was automated.  Given the current state of computerized image recognition, you probably can’t write a script that would magnify dogs or flowers or poison oak effectively.  Maybe in a few years.

There’s one last big problem, though.  And the last problem is about the colors alone.  There is simply no way to re-color images so that a dichromatic (colloquially, “colorblind”) human would see the world like a trichromat.

(A brief aside: Shortly after I wrote the above sentence, I read an article about glasses marketed to colorblind people to let them see color.  And the basic idea is clever, but I don’t think it invalidates my claim.

glasses

Here’s how it works: most colorblind people are dichromats, meaning they have two different flavors of color receptors.  Colored light stimulates these receptors differentially: green light stimulates green receptors a lot and blue receptors a little.  Blue light stimulates blue receptors a lot and green receptors a little.  The brain processes the ratio of receptor stimulation to say, “Ah ha!  That object is blue!”

A typical human, however, is a trichromat.  This means that the brain uses three datapoints to determine an object’s color instead of two.  The red and green receptors absorb maximally near the same part of the spectrum, though… the red vs. blue & green vs. blue ratios are generally very similar.  So the third receptor type mostly helps a trichromat distinguish between red and green.

This means a dichromat will have a narrower range of the electromagnetic spectrum that they are good at distinguishing color within.  For a dichromat, reds and greens both will be characterized by “green receptor stimulated a lot, blue receptor only a little.”

Now, if you imagine that the visual spectrum is number line that runs from 0 to 100, a dichromat would be good at distinguishing colors in the first 0 to 50 segment, and not good at distinguishing color beyond that point — everything with green wavelength, ca. 500 nanometers, and longer, would appear to be green.

But you could take that 0 to 100 number line and just divide everything by 2.  Then every color would look “wrong” — no object would appear to be the same color as it was before you put on the wacky glasses — and you’d be less able to distinguish between close shades — if two colors needed to be 15 nanometers apart to seem different, now they’d need to be 30 nanometers apart — but a dichromat could distinguish between colors over the same full visual spectrum as trichromats.

That’s roughly how the glasses should work — inbound light is shifted such that all colors are made blue & greenish, and the visual spectrum is condensed).

Of course, even though you can’t change an image in a way that will allow you (I’m assuming that you, dear reader, are a trichromat.  But my assumption has a 10% chance of being wrong.  My apologies!  I care about you, too, dichromatic reader!) and a dichromatic friend to see it the same way.  But you can change your friend.  You can inject a DNA-delivering retrovirus into your friend’s eyeball, and after a short neurological training period, you and your friend will see colors the same way!

Only in the eyeball!
Only in the eyeball!

It’s possible that your friend won’t like you any more if you do this.  But here’s how it works: the retrovirus encodes for the flavor of photoreceptor that none of your friend’s cone cells were expressing.  Upon infection, the virus will initiate production of that receptor… so now a subpopulation of cone cells will be sending new signals to the brain.  They’ll be stimulated by different wavelengths of light than they were before.  And brains, magically plastic things that they are, rapidly rewire themselves to incorporate any new data they have access to.

(If you’re interested in this sort of thing, you should look up biohacking.  Like implanting magnets in your fingers to “feel” electric or magnetic fields.  But I’m not going to link to anything.  Wrestling your friend to the ground in order to inject recombinant DNA into his eyeball?  That makes me smile.  But slicing open your own fingertips to put magnets under the skin?  That’s too creepy for me).

If a brain is suddenly receiving different signals after exposure to red versus green light, it’ll use that information.  Which means: Color vision achieved!  Unfortunately, viral DNA integrates randomly, so a weird eye cancer might’ve been achieved as well.  You win some, you lose some.

What we call “color vision,” though, is still only trichromatic.  With three flavors of cone cells, humans can do a pretty good job distinguishing colors from about 400 to 700 nanometers.  But some species have more flavors of cone cells, which means they can distinguish the world’s colors more precisely.  Even some humans are tetrachromats, although their fourth cone cell flavor is maximally stimulated by light midway between red and green, a part of the electromagnetic spectrum that trichromatic humans are already good at parsing.  And tetrachromatic humans are rare: to the best of my knowledge no languages have a word for that secret color between red and green.  I don’t know any words for it, at least, but maybe this too is a secret guarded by those who see it.

Still, no amount of image processing would allow you, dear reader, even if you’re one of those rare tetrachromatic individuals, to see the world in all the spangled glory seen by a starling or a peacock.  This graph shows the stimulation of each flavor of cone cell receptor by different wavelengths of light.

bird eyes

And even the splendorous beauty seen by birds pales in comparison to the way we thought mantis shrimps perceive the world.  Because mantis shrimps, see, have twelve flavors of photoreceptors, which means that if their brains processed colors the same ways ours do, by considering the ratio of cone cell flavors that are stimulated by incident light, they’d be exquisitely sensitive to color.  Here: compare the spectral sensitivity graph for humans and starlings, shown above, to the equivalent graph for mantis shrimps.  This makes humans look pathetic!

mantis shrimp spectral sensitivity

If you haven’t see it, you should definitely read this cartoon about mantis shrimp perception from The Oatmeal.

oatmealIt’s possible that mantis shrimps process color differently from humans, though.  Instead of computing ratios of cone-flavor activation to determine the color of an object, they might decide that an object is the color of whatever single cone flavor is most stimulated.  In other words, while humans use stimulation ratios from our mere three flavors of cone cells to identify thousands of hues, a species with a dozen photoreceptor flavors might regard every object as being one of those dozen discrete colors.

Indeed, that’s what a recent study from Thoen et al. (“A Different Form of Color Vision in Mantis Shrimp”) suggests.  They trained mantis shrimps to attack a particular color of light in order to win a treat, then tested how well it could distinguish that color from nearby wavelengths.  In their hands, the shrimps needed approximately 50 nanometers separating two colors to distinguish them, whereas humans, with our meager three flavors of photoreceptors, can often distinguish colors as close as 1 or 2 nanometers apart.

Still, it’s hard to know exactly what a shrimp is thinking.  Testing human cognition and perception is easier because we can, you know, talk to each other.  Describe what we see.

With humans, the biggest barrier to empathy is that sometimes we forget to listen.