Victor Norris had reached the final round in his application for a job working with young children, but he still had to undergo a psychological evaluation. Over two long November afternoons, he spent eight hours at the office of Caroline Hill, an assessment psychologist working in Chicago.

Norris had seemed an ideal candidate in interviews – charming and friendly, with a suitable résumé and unimpeachable references. Hill liked him. His scores were normal to high on the cognitive tests she gave him, as were his results on the personality test he took. When Hill showed him a series of pictures without captions and asked him to tell her a story about what was happening in each one – another standard assessment – Norris gave answers that were a bit obvious, but harmless enough.

At the end of the second afternoon, Hill asked Norris to move from the desk to a low chair near the couch in her office. She took out a yellow legal pad and a thick folder, and handed him, one by one, a series of 10 cardboard cards from the folder, each with a symmetrical blot on it. As she handed him each card, she said: “What might this be?”, or “What do you see?”

Five of the cards were in black and white, two had red shapes as well, and three were multicoloured. For this test, Norris was asked not to tell a story, not to describe what he felt, but simply to say what he saw. No time limit, no instructions about how many responses he should give. Any questions he asked were deflected:

“Can I turn it around?”

“It’s up to you.”

“Should I try to use all of it?”

“Whatever you like. Different people see different things.”

After he had responded to all 10 cards, Hill went back for a second pass: “Now I’m going to read back what you said, and I want you to show me where you saw it.”

Norris’s answers were shocking: elaborate, violent sexual scenes with children; parts of the inkblots seen as females being punished or destroyed. Hill politely sent him on his way – he left her office with a firm handshake and a smile, looking her straight in the eye – then she turned to the legal pad on her desk, with the record of his responses. She systematically assigned Norris’s responses the various codes of the standard method and categorised his answers as typical or unusual using the long lists in the manual. She then calculated the formulas that would turn all those scores into psychological judgments: dominant personality style, egocentricity index, flexibility of thinking index, the suicide constellation. As Hill expected, her calculations showed Norris’s scores to be as extreme as his answers.

If nothing else, the Rorschach test had prompted Norris to show a side of himself he did not otherwise let show. He was perfectly aware that he was undergoing an evaluation. He knew how he wanted to come across in interviews and what kind of bland answers to give on the other tests. On the Rorschach, his persona broke down. Even more revealing than the specific things he had seen in the inkblots was the fact that he had felt free to say them.

This was why Hill used the Rorschach. It’s a strange and open-ended task, in which it is not at all clear what the inkblots are supposed to be, or how you’re expected to respond to them. Crucially, it’s a visual task, so it can sometimes get around conscious strategies of self-presentation. As a postgraduate student, Hill had learned a rule of thumb that she had repeatedly seen confirmed in practice: a troubled personality can often keep it together on an IQ test and other standard tests, then fall apart when faced with the inkblots. When someone is intentionally or unintentionally suppressing other sides of their personality, the Rorschach might be the only assessment to raise a red flag.

Facebook Twitter Pinterest The Swiss psychiatrist Hermann Rorschach (1884-1922). Photograph: Alamy

Hill did not put in her report that Norris might be a past or future child molester – no psychological test has the power to determine that. She did conclude that Norris’s “hold on reality was extremely vulnerable”. She couldn’t recommend him for a job working with children and advised the employers not to hire him. They didn’t.

Norris’s disturbing results and the contrast between his charming surface and hidden dark side made a deep impression on Hill. Eleven years after giving that test, she received a phone call from a therapist who was working with a patient named Victor Norris and had a few questions he wanted to ask her. She didn’t need reminding who this person was. Hill was not at liberty to share the details of Norris’s results, but she laid out the main findings. The therapist gasped. “You got that from a Rorschach test? It took me two years of sessions to get to that stuff! I thought the Rorschach was tea leaves!”

Hermann Rorschach was a young Swiss psychiatrist who, working alone, tinkering with a children’s game, managed to create not only an enormously influential psychological test, but also a visual and cultural touchstone. He died in 1922, aged just 38, less than a year after publishing his test, and his short life was filled with tragedy, passion and discovery. Rorschach has been seen as a pioneering genius, bumbling dilettante, megalomaniac visionary, responsible scientist and just about everything in between.

Rorschach knew that he wanted to be a doctor from an early age, but at 19 he wrote to his sister: “I never again want to read just books, I want to read people … The most interesting thing in nature is the human soul, and the greatest thing a person can do is to heal these souls, sick souls.”

Rorschach’s family were not wealthy, but he managed to scrape together the funds to attend university and, a few weeks shy of his 20th birthday, he arrived in Zurich. In the early 1900s, Zurich had replaced Vienna as the epicentre of the Freudian revolution. Its university psychiatric clinic – known as the Burghölzli – became the first in the world to use psychoanalytic treatment methods. Rorschach’s supervisor, Eugen Bleuler, was a highly respected psychiatrist, and the first to bring the theories of Sigmund Freud into professional medicine. As a student, Rorschach attended lectures by Carl Jung.

In January 1908, in a lecture at Zurich town hall, Jung announced that “we have entirely abandoned the anatomical approach in our Zurich Clinic and have turned to the psychological investigation of mental disease”. Whether or not Rorschach attended this particular lecture, he certainly absorbed its message. He paid his dues in hard science, doing anatomical research on the pineal gland in the brain, but he agreed that the future of psychiatry lay in finding ways to interpret the mind.

While examining patients using various approaches, from hypnosis to word association, Rorschach found that what he needed was a method that could work in a single session, immediately producing what he called “a unified picture”. It would have to be structured, with specific things to respond to, like the prompts in a word-association test; unstructured, like the task of saying whatever comes into one’s head; and, like hypnosis, able to get around our conscious defences to reveal what we don’t know we know, or don’t want to know.

Inkblots had been used before, to measure the imagination, particularly in children, but in his early experiments, Rorschach showed people inkblots in order to discover what they saw, and how. As a lifelong amateur artist, the son of a drawing teacher, he knew that while a picture itself constrains how you see it, it does not take away all your freedom: different people see differently, and those differences are revealing. Rorschach originally thought of it as a perceptual experiment, not a diagnostic test. But he gradually realised that different kinds of patient – and people with different types of personality –showed systematic differences in how they saw the inkblots.

By the summer of 1918, Rorschach had written up his first inkblot experiments, describing the final 10 inkblots that he had created, along with the testing process and the basic scheme for interpreting the results. Rorschach decided that there were four important aspects of people’s responses. First, he noted the total number of answers given in the test as a whole, and whether or not the subject “rejected” any cards, refusing to answer at all. Second, he noted down whether each response described the whole inkblot or homed in on one part of it. Third, Rorschach categorised each answer according to what formal property of the image it was based on. Most answers were based on shapes: seeing a bat in a blot that’s bat‑shaped, a bear in a part of a blot that’s bear-shaped, and so on. He called these form (F) responses. Other answers focused on colour (C) or movement (M), or a mixture of these properties.

Facebook Twitter Pinterest Four Rorschach inkblot tests, 1921. Photograph: Science & Society Picture Library/Getty Images

Finally, Rorschach paid attention to the content of the answers – what people actually saw in the cards. He was as fascinated and delighted as anyone else by the unexpected, creative and sometimes bizarre answers given by test-takers. But what he mainly focused on was whether an answer was “good” or “poor” – whether it could reasonably be said to describe the actual shape in the blot. A form response would be marked as F+ for a well-seen form, F– for the opposite, F for the unexceptionable.

Right from the start, in his August 1918 manuscript, this raised a question that would continue to dog the Rorschach: Who decides what is reasonable? “Of course there need to be many tests of normal subjects with various kinds of intelligence, in order to avoid any personal arbitrariness in judging whether an F answer is good or bad. One will then have to classify many answers as objectively good that one would not subjectively call good.” Having just invented the test, Rorschach had no data that would let him objectively distinguish between good and bad – no set of norms. Establishing a quantitative baseline for which answers were common among normal test-takers, and which were unusual or unique, would be one of his first goals.

In his 1918 essay outlining the test, Rorschach described typical results for dozens of different subvarieties of mental illness, always careful to state when he lacked a sufficient number of cases to generalise safely. He insisted that these typical profiles, while they might seem arbitrary, had emerged in practice. A manic-depressive in a depressive phase, he wrote, will give no movement responses or colour responses, will see no human figures, and will tend to start with small details before moving to the whole (the reverse of the normal pattern), giving few whole responses overall. People with schizophrenic depression, on the other hand, will reject more cards, will occasionally give colour answers, will very often give movement answers, and will see a much smaller percentage of animals and significantly more poor forms. Why? Rorschach refused to speculate, but pointed out that this differential diagnosis – being able to tell the difference between manic-depressive and schizophrenic depression, “in most cases with certainty” – was a real medical breakthrough.

Despite decades of controversy, today the Rorschach test is admissible in court, reimbursed by medical insurance companies and administered around the world in job evaluations, custody battles and psychiatric clinics. The common habit of describing Brexit or Beyoncé or anything else as “a Rorschach test” – the implication being that there are no right or wrong answers; your reaction to it is what matters – coexists in a kind of alternate universe from the literal test given to patients, defendants and job applicants by psychologists. In these situations, there are very real right and wrong answers.

To the test’s supporters, these 10 inkblots – the same ones created and finalised in 1917 and 1918 – are a marvellously sensitive and accurate tool for showing how the mind works and detecting a range of mental conditions, including latent problems that other tests or direct observation cannot reveal.

To the test’s critics, both within and outside the psychology community, its continued use is a scandal – an embarrassing vestige of pseudoscience that should have been written off years ago, along with truth serum and primal-scream therapy. In their view, the test’s amazing power is its ability to brainwash otherwise sensible people into believing in it.

Partly because of this lack of professional consensus, and more because of a suspicion of psychological testing in general, the public tends to be sceptical about the Rorschach. The father in a recent well-publicised “shaken baby” case, who was eventually found innocent in the death of his infant son, thought the assessments he was subjected to were “perverse”, and particularly resented being given the Rorschach. “I was looking at pictures, abstract art, and telling them what I was seeing. Do I see a butterfly here? Does that mean I’m aggressive and abusive? It’s insane.”

The Rorschach test doesn’t yield a cut-and-dried result, as does an IQ test or a blood test. But then, nothing that tries to grasp the human mind could. For many years, the test was hyped as an X-ray of the soul. It isn’t, and it wasn’t originally meant to be, but it is a uniquely revealing window on the ways we understand our world.

The inkblots are widely used either to assign a diagnosis, or to change how a therapist understands a client. If a woman comes to see a psychologist for help with an eating disorder and then has a high suicide-index score on the Rorschach test, her psychologist might change their approach.

Examples such as this will seem suspect to psychologists or laymen who think the Rorschach finds something crazy in everyone. But as well as mental illness, the test is also used to determine mental health. Recently, at a state psychiatry facility in the US criminal justice system that houses people declared to be “not guilty by reason of insanity” or “incompetent to stand trial”, one violent man had been undergoing extensive treatment. The treatment seemed to have worked –the man’s psychotic symptoms were gone. To all appearances, he was no longer a danger to himself or others, but the team of doctors on his case was divided over whether he had really improved, or was faking health to get out of the facility. So they gave him a Rorschach test, which turned up no sign of thought disorders. The test was trusted enough as a reliable and sensitive indicator of such problems that the negative finding convinced the team and the man was released.

In spite of its detractors, the Rorschach continues to be used in a research context. It is often hard to distinguish between Alzheimer’s-type dementia and other effects of age and mental illness – so, could the inkblots tell them apart? In a 2015 conference, a Finnish scientist presented his analysis of Rorschach tests given to 60 patients in a Paris geriatrics unit, ages 51 to 93 (average age 79). Twenty of the patients had mild or moderate Alzheimer’s and 40 had a range of other mood disorders, anxiety, psychoses and neurological problems.

The test found many common elements between the two groups, but also a range of distinguishing features. Half a dozen Rorschach scores showed that Alzheimer’s patients were less psychologically resourceful, with less cognitive sophistication, creativity, empathy and problem-solving ability. They distorted information and did not integrate ideas and perceptions. Most intriguingly, despite putting a normal amount of effort into processing complex and emotional stimuli, Alzheimer’s patients gave fewer “human” responses – a kind of content response still generally accepted as an indication of interest in other people. The Alzheimer’s patients, more than their peers, had checked out of the social world. This finding was new in Alzheimer’s research, with implications for treatment and care.

Outside clinical psychology, the fact that there is so much data about how the inkblots are perceived makes them useful in a range of applications. In 2008, a team of Japanese neuroscientists wanted to study what happens when people see things in original ways, and needed recognised, standardised criteria for whether something a person sees is common, uncommon or unique. So they took what they called “10 ambiguous figures that have been used in previous studies” and projected them inside an MRI tube equipped with a voice scanner, tracking brain activity in real time as subjects gave typical or atypical answers to the inkblots.

The study demonstrated that seeing something in a “standard” way uses more instinctive, precognitive brain regions, while “original” vision, requiring a more creative integration of perception and emotion, uses other parts of the brain. As the Japanese scientists pointed out, Rorschachers had long argued precisely that original responses “are produced from the interference of emotion or personal psychological conflicts … on perceptual activities”. The MRI study confirmed Rorschach tradition, just as the inkblots had made the MRI experiment possible.

Other recent studies of perception have used new technologies to investigate the Rorschach test-taking process itself. Since typical test-takers give two or three responses per card on average, but can give nine or 10 when asked, a team of research psychologists at the University of Detroit argued in 2012 that people must be filtering or censoring their responses. Getting around this censorship might make a performance-based test more revealing. If only there were an involuntary reaction to an image, or at least a reaction “relatively more difficult to censor”. There was: our eye movements as we scan an inkblot before we speak.

So, building on eye-movement Rorschach studies going back to 1948, the researchers put a head-mounted eye-tracking device on 13 students, showed them the inkblots, and asked: “What might this be?”; then showed each blot again and asked: “What else might this be?”

They quantified and analysed the number of times each subject stopped and looked at one place on the image, how long they looked, how long it took to disengage from the whole image and start looking around, and how far the gaze jumped. They drew general conclusions, too, such as that we hold our gaze longer during second viewings, since reinterpreting an image is an “attempt to acquire conceptually difficult information”. This is paying attention to how we see, not what we say. Eye movements will never reveal as much about the mind as what we see in the inkblots, but researchers are exploring what they do show about how we see – and returning to Rorschach’s original vision of the test as a way to understand perception.

The most fundamental question about the test that Rorschach left unanswered at his death was how these 10 cards could produce such rich responses in the first place. The mainstream trend in psychology has been to leave aside this question of theoretical underpinning. Empiricists thought of the test as eliciting responses, and spent decades fine-tuning how those responses should be tabulated. For Rorschach – and for a few who came later – the inkblots elicited something deeper: a person’s whole way of seeing.

Seeing is an act of the mind, not just the eyes. When you look at something, you are directing your attention to parts of the visual field and ignoring others. You see the book in your hand or the ball hurtling toward you, and choose to disregard all the other information that is reaching your eye: the colour of your desk, the shapes of clouds in the sky. You are constantly cross-checking what is out there against objects and ideas you recognise and remember. Information and instructions are travelling along nerves from the eye to the brain, and from the brain to the eye. Stephen Kosslyn, one of today’s leading researchers into visual perception, monitored this two-way neural activity moving “upstream” and “downstream” during an act of seeing, and found that the ratio is 50-50. To see is to act as much as react, put out as much as take in.

Facebook Twitter Pinterest A doctor using the Rorschach test with a patient. Photograph: Orlando/Getty Images

Perception is not only a psychological process, it is also – almost always – a cultural one. We see through our personal and cultural lens, according to the habits of a lifetime, which are shaped by a particular culture. This helps explain why the question Rorschach asked in the test is so crucial. If we are asked “How does this make you feel?” or “Tell me a story about this scene”, that task does not test our perception. We can free-associate thoughts or feelings from inkblots, but for that purpose they are no better than clouds, stains, carpets or anything at all. Rorschach himself thought the inkblots were not especially well suited to free association. Being asked “What do you see?” or “What might this be?”, however, gets at how we process the world on the most basic level – and calls upon our whole personality and range of experience.

Nor is perception merely visual: “What might this be?” and “What do you see?” are not precisely the same question. But it was more than just personal preference or technological limitations that led Rorschach to use inkblots, rather than an audio Rorschach test or smell-o-blots. Vision is the sense that both operates at a distance, unlike touch and taste, and can be focused and directed, unlike hearing and smell. We can pay attention to certain noises or odours, or try to ignore them, but we cannot blink our ears or aim our nose: the eye is far more active, under far more control. Seeing is our best perceptual tool – our foremost way to engage with the world.

In principle, then, the Rorschach test rests on one basic premise: seeing is an act not just of the eye, but of the mind; and not just of the visual cortex or some other isolated part of the brain, but of the whole person. If that is true, a visual task that calls upon enough of our perceptual powers will reveal the mind at work.

I came to the inkblots not as a practising psychologist, nor as a crusader against personality testing. I had no axe to grind about whether the test, in whichever competing testing system, should be used more often or less often. Like many people, I was surprised to learn it was still used in clinics and courtrooms at all. I was curious about it as an artefact, then found out it was a real tool and wanted to learn more.

The first step was to take the test. At that point, I discovered that not just anyone knows how to give it, and the experts tend not to be inclined to indulge idle curiosity. I went looking for someone who knew all the techniques and formulas, but who also still saw the test as an exploration, something you could talk about. I was eventually referred to Dr Randall Ferriss.

Ferriss’s inkblot cards had not been used for some time. He rarely gives the test anymore. He works with defendants in the criminal justice system and does not want to find anything that might send them to jail. The last Rorschach test he gave before my visit was in a prison. Most test-takers there have a disturbed profile – no surprise, since prison is about as disturbing an environment as you can get. Ferriss was working with a young African American man on trial for carrying a gun. His brother had just been shot dead in South Central Los Angeles, and he knew he was a target. He came across as “angry and hostile”, as anyone would in those circumstances – so why give him a test? “You’re trying to tell his story,” Ferriss said. “You just don’t want to know how disturbed people are unless you’re diagnosing them in order to treat them.” But no one was considering giving this guy any treatment; only whether or not to lock him up and throw away the key.

How could the Rorschach test be improved for this defendant? Not by tweaking the scores and formulas, redefining administrative procedures or redoing the images, but using it to help, in a humane society, as part of a process of giving everyone who needs mental health care access to it.

To move past the dead-end Rorschach controversies of the past, and to use to the fullest the ways the test reveals our minds at work, we have to open up what we are asking of it. We have to return, in fact, to Hermann Rorschach’s own broadly humanistic vision.

In January 2002, it came to light that 40-year-old landlord Steven Greenberg of San Rafael, California, had been sexually molesting 12-year-old Basia Kaminska for more than a year. She was the daughter of an immigrant single mother who lived in one of his apartments. It later turned out that the abuse had gone on since she was nine. The police showed up at his house with a search warrant. Hours later, he drove to Petaluma municipal airport, took off in a single-engine plane, and flew it into Sonoma Mountain, leaving behind a minor media frenzy. Here – unlike in the story with which I began this piece – the names and identifying details have not been changed. Basia wants her story told.

When Basia was seen by a psychologist, her tendency to minimise and deny her problems made self-report tests basically useless. On the trauma symptom checklist for children – the Beck depression inventory, the Beck hopelessness scale, the children’s manifest anxiety scale and the Piers-Harris children’s self-concept scale – as well as in talking to the psychologist, she under-reported symptoms, said she had no feelings good or bad toward Greenberg, and claimed that she felt the events were behind her and she would rather not discuss them.

Only two tests gave trustworthy results. Her IQ, as measured by the Wechsler intelligence scale for children (WISC-III), was extremely high. And her scores on the Rorschach revealed emotional withdrawal, fewer psychological resources than one would think she possessed from the way she presented herself, and a deeply damaged sense of identity.

Her first response to Card I, the answer often interpreted as expressing one’s attitude about oneself, was something superficially conventional but telling. The blot is often seen as a bat. What Basia saw was a bat with holes in its wings: “See, here’s the head, the wings, but they’re all messed up, they’ve got holes. It looks like maybe somebody attacked them and that’s sad. It looks very ripped right here, and bat’s wings are usually precise. The wings would normally go out here. It sort of disrupts what it would normally be.” The rest of the test, both answers and scores, confirmed this first impression.

The examining psychologist wrote in her notes: “Very damaged and hanging on by her fingernails with a shield of sophistication.” Her report concluded that Basia was “clearly emotionally damaged as a result of traumatic circumstances, in spite of her cool exterior and protests to the contrary”.

Basia eventually sued Greenberg’s estate for damages, and four years later, the case went to court. The estate’s lawyers tried to use her earlier minimising and denying against her. Then the psychologist read to the jury Basia’s Rorschach response.

Why do we see so many different things in Rorschach ink blots? Read more

To be effective in a court of law, evidence has to be valid, but it also has to be vivid. Basia’s sad, messed-up bat had the ring of truth – it let the jury feel they had reached through the fog of prosecution and defence to this girl’s inner life, her real experience. It is not magic. Anyone who looked at Basia and felt sure that the girl was lying or faking would not have had their mind changed by this test result or anything else. But what Basia had seen in the inkblot told her story. It helped the people in the courtroom see her, deeply and clearly, in a way the other pieces of testimony could not.

No argument, no test or technique or trick, will get around the fact that different people experience the world differently. It is those differences that make us human beings, not machines. But our ways of seeing converge – or fail to converge – on something objective that is really there: interpretation, as Rorschach insisted, is not imagination. He created his enigmatic inkblots in an age when it was easier to believe that pictures could reveal psychological truth and touch on the deepest realities of our lives. And through all the reimaginations of the test, the blots remain.

Some names and identifying details in this story have been changed.

• This is an edited extract from The Inkblots: Hermann Rorschach, His Iconic Test, and the Power of Seeing by Damion Searls, published by Simon & Schuster on 23 February at £16.99. Buy it for £14.44 at bookshop.theguardian.com.

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