Non-Newtonian Fluid and the Human Psyche

Lance Rosenberger


There is a lot of praise out there comparing the human psyche to a figurative fluid. It makes sense if you don’t look too deep, as the human mind can adapt to new environments or problems in much the same way that a liquid fits any shaped vessel it is poured into. And much like an ever-flowing river, the human mind continues to work behind the scenes even when it appears to be at peace. It is such a popular analogy that you can hardly walk a block in any gentrified neighborhood without encountering a new age yoga studio promising peace of mind with such hot buzzwords as presence, adaptability, resonance, and (you guessed it) fluidity.

But I’m not here to hate on yuppies who make a living by stretching while cherry-picking Buddhist philosophy. That’s as overdone as innuendos about downward dogs. No, I’m here to debunk the traditional artsy metaphors of humans as ever-flowing rivers or lakes with hidden depths by presenting a new, more accurate (if less poetic) comparison:

The human psyche is Oobleck.

In case your childhood lacked in the same ways mine did, allow me to provide some context. Oobleck is a real-world substance that gets its name after Dr. Seuss’ Bartholomew and the Oobleck. In the story, when the King from the Kingdom of Didd becomes tired of regular weather, he orders his court wizards to create a new sort of weather that had never been seen before. The next day, sticky green globs of Oobleck starts raining from the sky and gumming up the whole kingdom. After quite the struggle, the King changes his ways and takes responsibility for his actions, even offering an “I’m sorry.” Just like that, all the Oobleck in the kingdom dissolves away, because apologizing and admitting fault is the real magic.

Unlike Dr. Seuss’ brainchild, real-world Oobleck is not made by wizards in a dank cave chanting nursery rhymes, but by mixing 1-part water with 1.5- to 2-parts corn starch and then adding food coloring to make it look less like a sad glue byproduct and more like something kids would want to stick in their mouths.

Suggestion: Do not let children stick Oobleck in their mouths. It tastes horrible.

“But wait,” you ask, “what makes Oobleck special?”

I’m glad you asked.

For starters, most fluids would be considered Newtonian fluids. This includes the coffee in your cup, the water in your toilet, and the air you breathe. Yes, the air. While the word fluid is often used to define a liquid, the definition actually encompasses anything that has no fixed shape and yields easily to external pressures. This includes gases.[1]

But unlike regular fluids, Oobleck is classified as a Non-Newtonian fluid, which are almost exclusively liquids. There are some exotic gaseous chemicals which when excited act in line with Non-Newtonian standards, but you are more likely to find those on gas giants like Jupiter than Earth.

This is the part where I start talking physics, but I’ll go slow for all the soft science people out there. The biggest difference between a Newtonian fluid and a Non-Newtonian fluid involves a thing called viscosity. Viscosity is a term defining the magnitude of internal friction—or in layman’s terms, thickness—that a material contains at a given moment. [2] A Newtonian fluid can be described by a single constant value of viscosity. If that wasn’t technical enough for you, a Newtonian fluid’s shear stress and strain rate scale in a steady, predictable manner.

In short: how “thick” a regular fluid feels doesn’t change based on how you interact with it. Water feels like water whether you are dipping your hand into it, punching it, or caressing it while whispering sweet nothings.

On the other hand, a Non-Newtonian fluid like Oobleck lacks a constant value describing their viscosity or flow.[3] Because of this, it might feel like water when you stick your hand in it, but feel like a solid when punched, or feel generally uncomfortable with your sweet caresses. This is because the relation between a Non-Newtonian’s shear stress and strain rate is nonlinear, and can even change depending on how long ago the appropriate force was applied (called a time-dependent variable).

There are plenty of fluids which deviate from Newton’s Law of Viscosity. Ketchup, toothpaste, and nail polish are all household examples of Non-Newtonian fluids, though their reactions to stress differ.

Oobleck is particularly interesting, because the more stress you apply to it—by, say, punching or stepping on it—the more it reacts like a solid. This means it is a dilatant—also known as a shear thickening fluid—and is such a pronounced feature of Oobleck that you can find plenty of videos online of people running or dancing across pools of the substance like a modern messiah figure trying to go viral.

And that is where the physics meets the metaphysics—and the metaphor.

The mind-is-fluid analogy does acknowledge how versatile humans can be as a species. We are barraged with information every day, and we adapt accordingly. However, the old analogy fails to acknowledge that this adaptability is dependent on the information lining up with our personal identities and worldview.

Humans are social animals, which has been a huge boon for us as a species. The sharing of information and technology, of combining hundreds of distinct cultures, has played a massive role in the advancement of our species. But we are not globally social. Our tribalism defines us, and as the world advances and we develop alongside it, we manage to be a part of more and more nuanced tribes. You can be Heterosexual, White, Male, Vegan, Christian, and Republican all at once just as easily as you could be a Bisexual, Pacific Islander, Gluten-Intolerant, Agnostic, Bipartisan, Trans-Woman. These are just some of the hundreds of tribes you might be a part of, and these traits determine every aspect of your life: who you hang out with, how you respond to other tribes, where you spend your free time, and even how much money you make.

But all of these distinct facets of one’s identity—of one’s very life and livelihood—have some interesting psychological side-effects.

One 2010 psychological study led by C. Nathan DeWall[4] proved that medicines which relieve physical pain by directly augmenting brain chemistry also relieved social stress (social pain). This study eventually led to the conclusion that social pain is felt in the same part of the brain as real, physical pain. Anyone who has ever been truly heartbroken can attest that the pain is just as real and world-shattering as any physical injury, even while you consciously know that there is nothing wrong with you. That’s because the same braincells telling you your ribs are literally broken are also responsible for informing you that someone just figuratively stomped your heart into the ground. Because the brain uses the same physical space and processes to handle both physical and emotional pain, it makes sense that the primal fight-or-flight response often associated with physical pain is just as common a reaction to social pains.

Whether it is intended as such or not, having information presented that goes against one’s worldview is treated by the mind as an attack. So, when you present someone with information that goes against their worldview, it is no coincidence that their response is often to attack by denying the validity of the information (“That’s not true”) or launching insults at your identity (“I guess a snowflake like you would say that”). If that doesn’t work, or hasn’t proven to work in their past, they might flee from the interaction (“I’m done with this conversation”) or remove themselves from the “hostile” environment altogether (“I unfriended/unfollowed him/her”). There is a term in psychology for when someone digs deeper into their beliefs when presented with identity-compromising information. Coined by study co-authors Brendan Nyhan and Jason Reifler, the “backfire effect” is a very real condition, and you are just as guilty of it as anyone else.[5]

In their study, Nyhan and Reifler asked parents to state on a scale how willing they were to vaccinate their children. After receiving this initial data, they had the parents read information regarding how vaccinations work, detailing the science behind the process. Afterwards, Nyhan and Reifler again asked parents to state their willingness to vaccinate their children. While most would assume that being better educated on a subject would have cleared up concerns, it actually had the opposite effect. Those who already were hesitant about vaccinations doubled down on their beliefs and said they were even less likely to vaccinate their children after reading the educational material than before.

Sadly, this is not an isolated incident. A series of studies led by Yale Professor Dan M. Kahan in 2007 suggests (and I say suggest in the same way that scientists call gravity a theory) that humans disproportionately and unintentionally misinterpret raw data to align with their worldview.[6] Even worse, the more educated someone was in a certain subject the more likely they were to misinterpret data regarding that subject to match their worldview. Kahan had his subjects fill out profiles defining their political associations, and then had them take basic tests to discern their affluency in various subjects. Then he presented them with batches of raw data, to see what conclusions were drawn. He did this many times, but one of the most interesting cases was when he presented his subjects with a profile of a scientist, complete with a list of academic achievements and honors. Everyone received the same profile, but some received works from said scientist stating that global warming was real, while others received works from him insisting it was false. Then Kahan asked the reader if they considered this scientist an expert in their field. Sadly, and unsurprisingly, whether the reader considered him an expert in his field depended more on if the findings aligned with their political beliefs, instead of the list of accomplishments and accolades.

This reaction to information is called Identity-Protective Cognition. As Kahan states, “As a way of avoiding dissonance and estrangement from valued groups, individuals subconsciously resist factual information that threatens their defining values.”[7]

If this sounds illogical, it is. And yet, it does make sense when viewed as a survival tactic. Earlier in this essay I made some disparaging remarks about yoga studios and those who use them. Right away, some die-hard yoga enthusiasts likely stopped reading in disgust. If you enjoy yoga and kept reading despite the bad taste my words left in your mouth, you are an incredibly open-minded person and deserving of praise. I mean that sincerely. You had the opportunity to dig deeper into your convictions and fervently deny my views, and I couldn’t really blame you. By acknowledging my words, you put your identity at risk by allowing potentially conflicting information to overshadow your previously held beliefs. Accepting yoga as a gentrified bastardization and abuse of eastern religious and philosophical practices would force you to change your ways, or live your life admitting to yourself that you just don’t care about cultural appropriation. You would have to find a different means of exercise, probably end up not hanging out with your yoga friends as much, get rid (or at least closet) your yoga gear. That’s a tremendous amount of work to change one small aspect of your identity. It is so much easier to just stop reading an essay.

Each person is a collection of tribes, each tribe a collection of triggers, of different pressures and counter pressures, stresses and reliefs. When dealing with most subjects, we slide and adapt to the shape of the vessel or environment we need to work with, just like water. But when our identity is attacked we harden up, we defend ourselves and those like us. We become stubborn in the face of conflicting facts. Water does not do that.

The human mind is incredibly adaptable, so long it is not attacked.

The human mind is Oobleck.


[1] Merriam-Webster Dictionary, “fluid”.

[2] Merriam-Webster Dictionary, “viscosity“.

[3] General Electric Company, “Non-Newtonian Fluid”. (2009)

[4] DeWall, C. Nathan; MacDonald, Geoff; D. Webster, Gregory; et al., “Acetaminophen Reduces Social Pain” (2010)

[5] Nyhan, Brendan; Reifler, Jason; et al. “Effective Messages in Vaccine Promotion: A Randomized Trial”. (2010)

[6] Kahan, Dan M.; et al., “Motivated Numeracy and Enlightened Self-Government”. (2013)

[7] Klein, Ezra. “How politics makes us stupid”. Vox (2014)



Provenance: Submission.


Lance Rosenberger’s first impression varies wildly on whether he has his beard or not that month. If he has it, you might suspect him of being a hipster craft beer snob that makes kale smoothies for breakfast. If he is clean shaven, you’d not be alone in assuming he is a good God-fearing man-child who gets squeamish at the sight of blood. The truth lies somewhere in between.



Featured Image: Public Domain via



No Comments

Leave a Reply