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A Nauseating Corner of Psychology: Disgust
Swamped this week. Here's a post originally published on my personal blog to fill the void.
Like many features of the human condition, the first psychological account of disgust comes from Charles Darwin, who in The Expression of the Emotions in Man and Animals defined it this way: “Something revolting, primarily in relation to the sense of taste, as actually perceived or vividly imagined; and secondarily to anything which causes a similar feeling, through the sense of smell, touch and even eyesight.” Theories of disgust bounced around following Darwin. Throughout the 20th century it was a niche area of research, but by the 1990s disgust was popular in psychology. Spearheading this movement was Paul Rozin, a clever psychologist who devised several experiments that revealed what elicits disgust. Think about eating soup from a sterilized bedpan or eating chocolate molded to resemble dog feces. Not pleasant, right? Rozin’s insight was that disgust is the “fear of incorporating an offending substance into one’s body.”
Disgust’s evolutionary origins are not a mystery. Humans are omnivores (we eat just about anything we can digest), so disgust acted as a food rejection system – a helpful emotional reminder that it’s not safe to feast indiscriminately. This is why carrion, vomit, feces, mucus, rotten meat, effluvia and other things loaded with dangerous microbes and parasites are so repulsive. Hundreds of thousands of years before Louis Pasteur discovered germ theory, natural selection had already endowed us with an implicit knowledge of it, which is why we not only refuse to eat said contaminates but also touch and think about them.
Disgust is universal but humans don’t express it until they are between three and four years old. In a slightly evil experiment Rozin and his colleagues found that children happily gobbled up dog feces (it was really peanut butter and smelly cheese) and grasshoppers. For parents, this study confirms the obvious: children younger than two put virtually everything in their mouths – a behavior Freud thought linked to sexuality (it doesn’t). Because disgust emerges a few years after birth it differs from culture to culture beyond a few universals. The mystery is: Why do different cultures develop disgust for different foods?
One line of reasoning is that disgust is a reaction to health issues. Many Jews believe that Judaism forbids pork because pigs are dirty. Some Muslims likewise think that the Islamic code that designates what foods are permissible for Muslims, Halal, bans the consumption of pork for health reasons. This explanation is plagued with inconsistencies. It’s true that pigs wallow in their own urine and eat feces. But this is also true of cows, dogs, and chickens under certain conditions.
Another possibility is that disgust was used to strengthen community bonds. As Steven Pinker puts it, food taboos “make the merest prelude to cooperation with outsiders – breaking bread together – an unmistakable act of defiance.” Judaism might have forbidden pork because the Philistines, who were the one of the Israelites’ main opponents, ate a lot of it. (H/T Geoff Mitelman)
The more plausible explanation comes from the anthropologist Marvin Harris. He argues that ecology played the dominant role, namely, that what food a culture deems disgusting is determined by the value of the animal the food comes from. In his 1974 book Cows, Pigs, War and Witches Harris observes in a chapter titled “Pig Lovers and Pig Haters” that Semites refuse to eat pork while people of highland New Guinea crave it. What explains this porcine paradox? Harris points out that North Africa and the Middle East, where Semites are from, lack vegetation including essential foods like nuts, fruits and vegetables. Pigs eat these foods as well, so domesticating them would be a burden on human nutritional needs. In contrast, vegetation in New Guinea is plentiful but protein is scarce. Pigs in New Guinea were therefore more valuable dead, cooked and eaten. All of this is consistent with the fact that kosher animals, including cattle, goats and sheep, survive off desert plants that are not valuable to humans. A similar example comes from Hinduism where slaughtering cattle is prohibited because (if Harris is correct) cattle pull plows and provide milk and manure. They are, in sum, worth more alive than dead.
Another question is how disgust and morality are related. A key piece of literature that addresses this question comes from a 2008 paper by Rozin, Jonathan Haidt and Clark McCauley. Building on previous research, they argue that communities co-opted a physical disgust for food and bodily functions into moral codes to establish rules about purity. If this is true it explains why cleanliness is a virtue in several cultures and religions including Hinduism where people are prohibited from wearing shoes when they walk on the courtyard of a temple. It also helps explain why the Abrahamic texts have so many rules concerning menstruation and sex. Western secular liberals might have trouble relating, but they are also disgusted when, for example, a person’s rights or dignity is violated.
Under this paradigm our disease avoidance system “spilled over” into our moral codes. This seems like a reasonable theory. For example, there are plenty of things I find disgusting that Idon’t make a moral judgment about. In a recent Bloggingheads conversation between Paul Bloom and David Pizarro (leading researchers in the field), Pizarro points out that he finds nose picking disgusting but he does not make moral judgments about nose picking or nose pickers. Similarly, Bloom says cheekily, a poopy diaper might be gross but no one would blame the kid for pooping. Another idea is that the disgust for dangerous foods and bodily functions and the disgust for other things including people, practices and ideas are one in the same. However, a lack of evidence makes it difficult to determine which one of these theories is more plausible at this point in time.
Disgust, it should be said, is not necessarily a good guide for morality. Liberals in the United States criticize homophobic conservatives for deeming homosexual sex immoral just because they find it disgusting, implying that disgust is not a sufficient justification. But when the same liberal thinkers are pressed to explain why things like child molestation, incest or having sex with chickens are immoral they encounter the same problem: moral dumbfounding – what’s intuitively obvious is not always morally correct. Disgust, in other words, is not a reliable source for moral guidance. Leon Kass makes this point in an essay he penned many years ago:
Revulsion is not an argument; and some of yesterday’s repugnancies are today calmly accepted — though, one must add, not always for the better. In crucial cases, however, repugnance is the emotional expression of deep wisdom, beyond reason’s power fully to articulate it. Can anyone really give an argument fully adequate to the horror which is father-daughter incest (even with consent), or having sex with animals, or mutilating a corpse, or eating human flesh, or even just (just!) raping or murdering another human being? Would anybody’s failure to give full rational justification for his or her revulsion at these practices make that revulsion ethically suspect? Not at all. On the contrary, we are suspicious of those who think that they can rationalize away our horror, say, by trying to explain the enormity of incest with arguments only about the genetic risks of inbreeding.
A scary consequence of morality based on disgust is what happens when it is extended to out-groups. Sometimes a community will lump members of an out-group into a category and equate it with what’s physically disgusting. This is one hallmark of ethnic cleansings and it occurred during the Rwandan genocide when the Hutus equated Tutsis with “cockroaches.” To paraphrase Haidt, moral rules based on disgust bind and blind.
So what is disgust? It is a disease avoidance system put in place by natural selection to prevent us from consuming harmful food and bodily fluids. Effluvia, vomit, feces, rotten flesh, and urine are disgusting to people around the world. It can’t be a coincidence that these substances contain dangerous diseases. The question is how disgust emerges in different cultures. Harris postulates that it relates to ecology and economics. I mentioned that it’s possible that disgust evolved not just as a disease-prevention system but also as a tool to distinguish “us” from “them”. However, it seems more likely that disgust for anything that is not food or a bodily fluid is a byproduct of a disease-prevention system.
Sometimes disgust results in quirky behavior. People are disgusted by the thought of wearing the socks of a rapist or Hitler’s sweater. Other times disgust is more significant, especially when large groups of people label other groups disgusting. From the trivial to the consequential, it’s important that disgust doesn’t guide morality. I hope people are rational enough to realize this.
In the last two decades psychological science has conducted brilliant research to uncover what Darwin described nearly 150 years ago in The Expression of the Emotions in Man and Animals. A lot of credit goes to Paul Rozin, but other researchers including Bloom, Pizarro (and their colleagues Yoel Inbar and Ravi Iyer), and Haidt are providing insightful findings with clever experiments. If the next twenty years are as fruitful as the last we’ll have a much more complete picture of this nauseating corner of human psychology.
 From Rozin, Haidt and McCauley 2008
 From Pinker 1997.
 Leviticus 11:7-8 “And the swine, though he divide the hoof, and be clovenfooted, yet he cheweth not the cud; he [is] unclean to you. Of their flesh shall ye not eat, and their carcase shall ye not touch; they [are] unclean to you.”
 Leviticus 15:19-30 “And if a woman have an issue, and her issue in her flesh be blood, she shall be put apart seven days: and whosoever toucheth her shall be unclean until the even.”
 Kass does not conclude that it is correct.
Inventions with revolutionary potential made by a mysterious aerospace engineer for the U.S. Navy come to light.
- U.S. Navy holds patents for enigmatic inventions by aerospace engineer Dr. Salvatore Pais.
- Pais came up with technology that can "engineer" reality, devising an ultrafast craft, a fusion reactor, and more.
- While mostly theoretical at this point, the inventions could transform energy, space, and military sectors.
The U.S. Navy controls patents for some futuristic and outlandish technologies, some of which, dubbed "the UFO patents," came to life recently. Of particular note are inventions by the somewhat mysterious Dr. Salvatore Cezar Pais, whose tech claims to be able to "engineer reality." His slate of highly-ambitious, borderline sci-fi designs meant for use by the U.S. government range from gravitational wave generators and compact fusion reactors to next-gen hybrid aerospace-underwater crafts with revolutionary propulsion systems, and beyond.
Of course, the existence of patents does not mean these technologies have actually been created, but there is evidence that some demonstrations of operability have been successfully carried out. As investigated and reported by The War Zone, a possible reason why some of the patents may have been taken on by the Navy is that the Chinese military may also be developing similar advanced gadgets.
Among Dr. Pais's patents are designs, approved in 2018, for an aerospace-underwater craft of incredible speed and maneuverability. This cone-shaped vehicle can potentially fly just as well anywhere it may be, whether air, water or space, without leaving any heat signatures. It can achieve this by creating a quantum vacuum around itself with a very dense polarized energy field. This vacuum would allow it to repel any molecule the craft comes in contact with, no matter the medium. Manipulating "quantum field fluctuations in the local vacuum energy state," would help reduce the craft's inertia. The polarized vacuum would dramatically decrease any elemental resistance and lead to "extreme speeds," claims the paper.
Not only that, if the vacuum-creating technology can be engineered, we'd also be able to "engineer the fabric of our reality at the most fundamental level," states the patent. This would lead to major advancements in aerospace propulsion and generating power. Not to mention other reality-changing outcomes that come to mind.
Among Pais's other patents are inventions that stem from similar thinking, outlining pieces of technology necessary to make his creations come to fruition. His paper presented in 2019, titled "Room Temperature Superconducting System for Use on a Hybrid Aerospace Undersea Craft," proposes a system that can achieve superconductivity at room temperatures. This would become "a highly disruptive technology, capable of a total paradigm change in Science and Technology," conveys Pais.
High frequency gravitational wave generator.
Credit: Dr. Salvatore Pais
Another invention devised by Pais is an electromagnetic field generator that could generate "an impenetrable defensive shield to sea and land as well as space-based military and civilian assets." This shield could protect from threats like anti-ship ballistic missiles, cruise missiles that evade radar, coronal mass ejections, military satellites, and even asteroids.
Dr. Pais's ideas center around the phenomenon he dubbed "The Pais Effect". He referred to it in his writings as the "controlled motion of electrically charged matter (from solid to plasma) via accelerated spin and/or accelerated vibration under rapid (yet smooth) acceleration-deceleration-acceleration transients." In less jargon-heavy terms, Pais claims to have figured out how to spin electromagnetic fields in order to contain a fusion reaction – an accomplishment that would lead to a tremendous change in power consumption and an abundance of energy.
According to his bio in a recently published paper on a new Plasma Compression Fusion Device, which could transform energy production, Dr. Pais is a mechanical and aerospace engineer working at the Naval Air Warfare Center Aircraft Division (NAWCAD), which is headquartered in Patuxent River, Maryland. Holding a Ph.D. from Case Western Reserve University in Cleveland, Ohio, Pais was a NASA Research Fellow and worked with Northrop Grumman Aerospace Systems. His current Department of Defense work involves his "advanced knowledge of theory, analysis, and modern experimental and computational methods in aerodynamics, along with an understanding of air-vehicle and missile design, especially in the domain of hypersonic power plant and vehicle design." He also has expert knowledge of electrooptics, emerging quantum technologies (laser power generation in particular), high-energy electromagnetic field generation, and the "breakthrough field of room temperature superconductivity, as related to advanced field propulsion."
Suffice it to say, with such a list of research credentials that would make Nikola Tesla proud, Dr. Pais seems well-positioned to carry out groundbreaking work.
A craft using an inertial mass reduction device.
Credit: Salvatore Pais
The patents won't necessarily lead to these technologies ever seeing the light of day. The research has its share of detractors and nonbelievers among other scientists, who think the amount of energy required for the fields described by Pais and his ideas on electromagnetic propulsions are well beyond the scope of current tech and are nearly impossible. Yet investigators at The War Zone found comments from Navy officials that indicate the inventions are being looked at seriously enough, and some tests are taking place.
If you'd like to read through Pais's patents yourself, check them out here.
Laser Augmented Turbojet Propulsion System
Credit: Dr. Salvatore Pais
How imagining the worst case scenario can help calm anxiety.
- Stoicism is the philosophy that nothing about the world is good or bad in itself, and that we have control over both our judgments and our reactions to things.
- It is hardest to control our reactions to the things that come unexpectedly.
- By meditating every day on the "worst case scenario," we can take the sting out of the worst that life can throw our way.
Are you a worrier? Do you imagine nightmare scenarios and then get worked up and anxious about them? Does your mind get caught in a horrible spiral of catastrophizing over even the smallest of things? Worrying, particularly imagining the worst case scenario, seems to be a natural part of being human and comes easily to a lot of us. It's awful, perhaps even dangerous, when we do it.
But, there might just be an ancient wisdom that can help. It involves reframing this attitude for the better, and it comes from Stoicism. It's called "premeditation," and it could be the most useful trick we can learn.
Broadly speaking, Stoicism is the philosophy of choosing your judgments. Stoics believe that there is nothing about the universe that can be called good or bad, valuable or valueless, in itself. It's we who add these values to things. As Shakespeare's Hamlet says, "There is nothing either good or bad, but thinking makes it so." Our minds color the things we encounter as being "good" or "bad," and given that we control our minds, we therefore have control over all of our negative feelings.
Put another way, Stoicism maintains that there's a gap between our experience of an event and our judgment of it. For instance, if someone calls you a smelly goat, you have an opportunity, however small and hard it might be, to pause and ask yourself, "How will I judge this?" What's more, you can even ask, "How will I respond?" We have power over which thoughts we entertain and the final say on our actions. Today, Stoicism has influenced and finds modern expression in the hugely effective "cognitive behavioral therapy."
Helping you practice StoicismCredit: Robyn Beck via Getty Images
One of the principal fathers of ancient Stoicism was the Roman statesmen, Seneca, who argued that the unexpected and unforeseen blows of life are the hardest to take control over. The shock of a misfortune can strip away the power we have to choose our reaction. For instance, being burglarized feels so horrible because we had felt so safe at home. A stomach ache, out of the blue, is harder than a stitch thirty minutes into a run. A sudden bang makes us jump, but a firework makes us smile. Fell swoops hurt more than known hardships.
What could possibly go wrong?
So, how can we resolve this? Seneca suggests a Stoic technique called "premeditatio malorum" or "premeditation." At the start of every day, we ought to take time to indulge our anxious and catastrophizing mind. We should "rehearse in the mind: exile, torture, war, shipwreck." We should meditate on the worst things that could happen: your partner will leave you, your boss will fire you, your house will burn down. Maybe, even, you'll die.
This might sound depressing, but the important thing is that we do not stop there.
Stoicism has influenced and finds modern expression in the hugely effective "cognitive behavioral therapy."
The Stoic also rehearses how they will react to these things as they come up. For instance, another Stoic (and Roman Emperor) Marcus Aurelius asks us to imagine all the mean, rude, selfish, and boorish people we'll come across today. Then, in our heads, we script how we'll respond when we meet them. We can shrug off their meanness, smile at their rudeness, and refuse to be "implicated in what is degrading." Thus prepared, we take control again of our reactions and behavior.
The Stoics cast themselves into the darkest and most desperate of conditions but then realize that they can and will endure. With premeditation, the Stoic is prepared and has the mental vigor necessary to take the blow on the chin and say, "Yep, l can deal with this."
Catastrophizing as a method of mental inoculation
Seneca wrote: "In times of peace, the soldier carries out maneuvers." This is also true of premeditation, which acts as the war room or training ground. The agonizing cut of the unexpected is blunted by preparedness. We can prepare the mind for whatever trials may come, in just the same way we can prepare the body for some endurance activity. The world can throw nothing as bad as that which our minds have already imagined.
Stoicism teaches us to embrace our worrying mind but to embrace it as a kind of inoculation. With a frown over breakfast, try to spend five minutes of your day deliberately catastrophizing. Get your anti-anxiety battle plan ready and then face the world.
A study on charity finds that reminding people how nice it feels to give yields better results than appealing to altruism.
- A study finds asking for donations by appealing to the donor's self-interest may result in more money than appealing to their better nature.
- Those who received an appeal to self-interest were both more likely to give and gave more than those in the control group.
- The effect was most pronounced for those who hadn't given before.
Even the best charities with the longest records of doing great fundraising work have to spend some time making sure that the next donation checks will keep coming in. One way to do this is by showing potential donors all the good things the charity did over the previous year. But there may be a better way.
A new study by researchers in the United States and Australia suggests that appealing to the benefits people will receive themselves after a donation nudges them to donate more money than appealing to the greater good.
How to get people to give away free money
The postcards that were sent to different study subjects. The one on the left highlighted benefits to the self, while the one on the right highlighted benefits to others.List et al. / Nature Human Behaviour
The study, published in Nature Human Behaviour, utilized the Pick.Click.Give program in Alaska. This program allows Alaska residents who qualify for dividends from the Alaska Permanent Fund, a yearly payment ranging from $800 to $2000 in recent years, to donate a portion of it to various in-state non-profit organizations.
The researchers randomly assigned households to either a control group or to receive a postcard in the mail encouraging them to donate a portion of their dividend to charity. That postcard could come in one of two forms, either highlighting the benefits to others or the benefits to themselves.
Those who got the postcard touting self-benefits were 6.6 percent more likely to give than those in the control group and gave 23 percent more on average. Those getting the benefits-to-others postcard were slightly more likely to give than those receiving no postcard, but their donations were no larger.
Additionally, the researchers were able to break the subject list down into a "warm list" of those who had given at least once before in the last two years and a "cold list" of those who had not. Those on the warm list, who were already giving, saw only minor increases in their likelihood to donate after getting a postcard in the mail compared to those on the cold list.
Additionally, the researchers found that warm-list subjects who received the self-interest postcard gave 11 percent more than warm-list subjects in the control group. Amazingly, among cold-list subjects, those who received a self-interest postcard gave 39 percent more.
These are substantial improvements. At the end of the study, the authors point out, "If we had sent the benefits to self message to all households in the state, aggregate contributions would have increased by nearly US$600,000."
To put this into perspective, in 2017 the total donations to the program were roughly $2,700,000.
Is altruism dead?
Are all actions inherently self-interested? Thankfully, no. The study focuses entirely on effective ways to increase charitable donations above levels that currently exist. It doesn't deny that some people are giving out of pure altruism, but rather that an appeal based on self-interest is effective. Plenty of people were giving before this study took place who didn't need a postcard as encouragement. It is also possible that some people donated part of their dividend check to a charity that does not work with Pick.Click.Give and were uncounted here.
It is also important to note that Pick.Click.Give does not provide services but instead gives money to a wide variety of organizations that do. Those organizations operate in fields from animal rescue to job training to public broadcasting. The authors note that it is possible that a more specific appeal to the benefits others will receive from a donation might prove more effective than the generic and all-inclusive "Make Alaska Better For Everyone" appeal that they used.
In an ideal world, charity is its own reward. In ours, it might help to remind somebody how warm and fuzzy they'll feel after donating to your cause.
The 'Monkeydactyl' was a flying reptile that evolved highly specialized adaptations in the Mesozoic Era.