The Most Resilient Parasite

Christopher Nolan's Inception and viral ideas


in Features • Illustrated by Alex Hotchkiss


That nagging feeling had me. I couldn’t get the movie out of my brain, knew I wouldn’t be able to until I watched it. I could see Ariadne manipulate full-scale cities, hear Cobb lay out his plans to penetrate an unaware victim’s mind, feel the tension as Fischer is confronted with his father’s disappointment. All set to Hans Zimmer’s daunting score in the background. But why had these flashes trespassed upon my consciousness? What tied these scenes together? My mind had latched onto some trope, emotional trigger, an intellectual concept from the film. 

Often when this invasion happens, weeks or months pass before I finally get my butt on the couch for the requisite two hours. This time, though, I was too stuck to move on. It was an idyllic 78 degrees outside, the sun’s beams cut by a crisp breeze. The kind of weather that doesn’t last here in Texas. But that precious afternoon I sat inside, lowered the shades in search of a theater-like experience, and rewatched Christopher Nolan’s Inception.  

I listened to the ominous soundtrack, was settling in to enjoy the charismatic Leonardo DiCaprio as the protagonist Cobb. Then BAM, two minutes in, Cobb gets right to the point. The point for me, at least — always the physician. “What is the most resilient parasite? A bacteria? A virus? An intestinal worm? An idea. Resilient . . . highly contagious. Once an idea has taken hold of the brain it’s almost impossible to eradicate. An idea that is fully formed — fully understood — that sticks,” he taps on his cranium, “right in there somewhere.” Cobb voices the presupposition for Nolan’s plot: that an idea can be planted into someone’s mind, and as long as the person believes it stems from their own psyche, that idea can then use its new home to propagate, grow, and ultimately dominate the host. 

Cobb is what’s called an extractor in this cinematic universe. He has made a living taking precious information from others’ minds by entering a dream world with them and victimizing their subconscious selves. He is an expert. We know he can do this. No big deal. Inception’s drama, however, follows Cobb’s attempts to perform the opposite: implanting an idea rather than stealing information. He is paid well for his work as an extractor; his attempt to perform inception, a feat believed by even the best in his field to be impossible, has the higher stakes of buying his way back into the United States, from which he has been forced out, and reclaiming his children. 

Already robbed of a lowkey, relaxed movie day, I’d identified the concept that had been gnawing at my neurons. It wasn’t the scenes themselves, but rather how the plot analogizes an important scientific concept. Important being the understatement of the millennium. Cobb breezed right past the biological examples, but there was more there, begging to be explored. While bacteria and worms can take over and lead to the demise of a host, a virus is akin to Nolan’s concept of an idea. Ideas don’t possess their own machinery for reproduction. They can’t change or evolve on their own. Moreover, their entire existence depends on interpretation. Without a host, an idea is nothing: a play without an audience. 

Similarly, a virus is nothing without a victim. It is essentially genetic material. And . . . that’s it. Viruses can’t replicate themselves and most fizzle out almost immediately when not contained within a more complex organism. Viruses are energy-less. Viruses are obligate intracellular parasites — they can only reproduce within the cell of a host organism. They need us. Ideas and viruses can seem to take on lives of their own, but really they’re inextricably dependent on larger, more tangible beings. We grant them power.  

Leo’s character, Cobb, and his assembled team of misfits — four other handpicked specialists — are given the task to plant an idea into the mind of Fischer. Their concern is not so much the content of the idea, but rather that it is simple — “You need the simplest version of the idea in order for it to grow naturally in the subject’s mind.” Nolan himself explained in an interview his predilection for choosing one-word movie titles: “I’ve always gravitated towards the simplest version of something that gets it across.” (Funny, I’d never imagined Nolan trying to do anything simple.) Fischer must also think the idea was his, and the seed should lead to the outcome of Fischer splitting up his dead father’s company.  

Why? Cobb’s employer, Saito, is the head of a rival company, being crushed by the Fischer family’s dominating empire.  

The misfits spend the beginning of the film holding brainstorming sessions. They sit arranged in a haphazard group of folding chairs, old office chairs, and what look to be pool recliners, dwarfed in the massive warehouse that has become their work area. Cobb, always looking sharp in a crisp button-down with his hair slicked back, points at bulletin boards fitting for the visual medium of the big screen, rolls up his sleeves, and wrangles the team. The group often disagrees, but eventually generates a simple concept to implant in Fischer’s mind: “My father doesn’t want me to be him.”  

At this point, almost an hour in, the movie was gaining momentum. Though still sitting in artificial darkness on my couch, I was gathering momentum in a different direction. I hit pause, went to the closet in the spare room, and dug through a mountain of wrapping paper, outdated electronics, and abandoned musical instruments. Aha! Underneath the junk, pushed way into the back corner, were my two file boxes of archived medical school notes. Contrary to what people may think, clinicians almost never think about basic science. Time for a refresher.  

A virus is genetic material, RNA or DNA, the most basic form of information, surrounded by a capsid, or protein coat. There are no organelles or ribosomes, the machinery of normal cells for the simplest viruses. And for a naked virus, that’s it. More modest viruses are enveloped by a lipid bilayer membrane. Proteins on the virus’s exterior dock to receptors on those of a host cell. On the surface of influenza virions, for example, are hemagglutinin and neuraminidase, the H and N from H1N1 (swine flu) or H5N1 (avian flu), or H insert-number-here N insert-number here. Hemagglutinin binds to a type of sugar, sialic acid, on the surface of a cell it aims to infect. Neuraminidase helps to expose that binding site, and later cleaves the virus when it is ready to move on and infect other cells.  

Once bound to receptors, the virus can fuse with the host cell, shedding its membrane to join the cell’s, or enter via endocytosis, essentially being swallowed up by the cell’s membrane and spit out on the other side. Inside the cell, reaching its target of action, the virus uncoats. The capsid releases the DNA or RNA. DNA joins up with the cells machinery for viral replication in the nucleus. RNA sits in the cytoplasm for replication, the gel-like fluid that fills the cell, like the vitreous humor in the human eye. The viral products assemble into additional viruses, and the virus exits the way it came in, either being swallowed up and spit out by the host cell membrane (exocytosis), or budding through the membrane, keeping a piece as its own, new coat.  

Cobb and his team, dressed as rich businessmen, board the first-class section of a transatlantic flight with Fischer, who is traveling to attend his father’s funeral. Cobb slips a sedative in Fischer’s drink, and the whole team, reclining on the plush, tan leather seats that I’m guessing clock in at $10,000 a ticket, takes their created seed of an idea with them to enter Fischer’s dream world, thus exposing them to his subconscious.  

They need Fischer to believe the idea “my father doesn’t want me to be him.” This is supposed to fester, and evolve, into further thoughts like “my father wants me to be my own man and create for myself” and eventually “My father wants me to split up his company and start fresh.” The team doesn’t possess equipment to propagate the idea, making it grow and eventually transform into actions. There is no such equipment. Fischer’s mind must do that — “when we get inside his mind, we’re gonna have to work with what we find.” The team relies on his machinery, in a sense using Fischer against himself, tricking his mind into doing their dirty work. 

Viruses travel by droplets of mucus or spit, fecal-to-oral route, the blood, something that allows them to get to their target cells. Those in respiratory droplets tend to affect the throat and lungs, those with fecal-to-oral transmission tend to affect the GI system, and those in the blood, well, can go pretty much anywhere. When a virus injects its DNA into a host cell, it usurps the cell’s machinery, intended for replicating the self, for instead pumping out its own particles.  

If the virus’s genetic material is DNA, that DNA must be transcribed to RNA using RNA polymerase, a type of minute machinery that matches pieces of RNA to their corresponding DNA patterns. Further proteins the virus needs, those that form its capsid, must be translated with the host cell’s ribosomes, which this time links pieces of proteins to their corresponding RNA patterns. DNA is transcribed to RNA. RNA is translated to proteins, the final product. Transcribe. Translate. Repeat.  

This is how most viruses work; however, there are exceptions. HIV, for example, a retrovirus, has to bring some equipment with it. Retroviruses require the enzymes protease, integrase, and reverse transcriptase in order to make RNA into DNA and insert runs of this into the host cell’s DNA. As humans have no need to turn RNA into DNA, the virus has to carry these enzymes with it in its capsid. Some oncoviruses, those viruses that have the potential to cause cancer, are either retroviruses (HTLV-1) that convert their own RNA into DNA and insert it into the host cell’s DNA, or DNA viruses (like HPV, hepatitis B, Epstein-Barr virus) E that can insert themselves directly. This marring of our own DNA can mess up the genes we need to prevent cancer and interfere with the proteins those genes produce.  

Cobb’s dream team runs into a problem. Seconds after entering their first dream world and through this Fischer’s subconscious, a train barrels down the middle of a busy street, smashing into cars and wreaking havoc. That was not part of the design. Mercenary-like men in all black, with high-tech weapons and good aim, shoot down at them from the tops of skyscrapers. These are parts of Fischer, projections, fighting against the invaders.  

We learned earlier when Cobb was teaching Ariadne, a team member new to dream worlds, that the mind would revolt against something perceived as foreign. She and Cobb entered his mind together for her to practice her craft. As Ariadne changed things in his mind, making huge mirrors appear on a bridge, flipping part of the world in its side, she noticed the other people in the dream, Cobb’s subconscious, focused on her: 

Ariadne: “Why are they all looking at me?” 

Cobb: “Because my subconscious feels that someone else is creating this world. The more you change things, the quicker the projections start to converge on you.” 

Ariadne: “Converge?” 

Cobb: “It’s the foreign nature of the dreamer. They attack like white blood cells fighting an infection.” 

But this took the projections a while. Ariadne wasn’t immediately recognized as an invader. She had time to work. The team thought they would have time to work in Fischer’s mind; on the contrary, they were immediately detected and assaulted.  

I put down the notes on cellular machinery I’d found in the first box, under the topic of biochemistry, my first class in medical school. I had to go deeper, crack open the second box, containing the notes from year two, and find the immunology course. Another refresher.  

Physical barriers like the skin and mucus membranes, followed by the body’s innate immune system — white blood cells of varying types, cytokines — defend against the majority of threats that humans encounter. White blood cells called macrophages (Greek for “large eater”) engulf invaders and destroy them. But the innate immune system is shit against viruses. Viruses are too small, too varied, and they hide inside our own cells. For this, our body has an adaptive immune system, which likely developed as a defense against viruses.  

A specialized type of white blood cell called B lymphocytes carries receptors on their surface. They travel around the blood searching out the specific cognate antigen for their receptor, the puzzle piece that fits. If the B lymphocyte finds its target, it goes into overdrive, making a bunch of itself, as well as the receptors on its surface, in a process called clonal selection. These receptors, it turns out, are antibodies. They are made up of modular segments, able to produce millions of different products, or changing heads, to bind to as many different targets. The antibodies get released from the B cells and travel the bloodstream, binding on the modular side to their antigen, the invader, and on the other static side to the macrophages. Antibodies function as a bridge between invader and destroyer.  

For viruses that are inside host cells and can’t be accessed by antibodies, T lymphocytes look for signals on the surface of host cells that they have been infected. Our cells will take parts of the virus and display them outside the cell as a sign of an invader, waving a flag that they’ve been compromised. If the T lymphocyte detects this, it will trigger the host cell to commit suicide, solving the “hiding virus” problem. 

The production of extra lymphocytes and antibodies is time-consuming. The body ramps up production when it realizes they’re needed, but this process isn’t immediate. Then most B and T lymphocytes are destroyed after they have done their job on the virus. They have to be, otherwise, our blood would be viscous, like sludge, with white blood cells. But our body keeps around memory cells with the receptor that matches the antigen — we keep more lymphocytes around than we had before, and they are easier to activate, primed to action.  

These memory cells roam the blood in a quiescent state for decades, seeking out their target. The next time the virus comes around, it is recognized quickly, and the body embarks upon antibody production much more swiftly. This may confer immunity against the virus, leaving the invader no foothold to begin production, or it may mean that the virus causes a less severe illness, of shorter duration. 

While Fischer hasn’t actually been attacked by extractors (or inceptioners) before, he has been exposed to them in some way. Likely he was given practice versions to defend himself against, knowing that his immense wealth and power make him a target. The practice versions weren’t the real thing, but they were close. After being recognized and attacked so quickly, the team realizes “Fischer’s had an extractor teach his subconscious to defend itself, so, his subconscious has militarized.” Fischer has been inoculated against their particular kind of invader.  

Fischer’s training is most akin to vaccination. Vaccination is presenting the body with a dead or weakened version of an infective organism, or sometimes simply synthetic parts of it (as with the HPV vaccine, which wasn’t taken from the virus but created from scratch). This triggers the body to form antibodies against the culprit, as well as the lymphocytes that will become memory cells. The word vaccine comes from the Latin of cow, when back in 1790 Edward Jenner, widely considered the founder of immunology, created the first vaccine for smallpox by inoculating subjects with cowpox, a similar but less pernicious virus.  

Some vaccines are great, practically foolproof, as with MMR, the vaccine for measles, mumps, and rubella. The protein on the surface of measles, for example, that both allows for recognition by the immune system and for it to enter host cells essentially does not change; studies have shown that if this protein mutates, the virus can no longer enter the host cell. So the antigen is always the same in any infective form of measles. Like, if Fischer’s body had seen Cobb and his exact team before and knew to the tiniest detail what they were going to do. He would cut them off at every turn. They wouldn’t have a chance.  

Other vaccines, however, are less successful. The flu vaccine must fight against multiple, changing strains. The CDC has to pick three flu strains predicted to be prominent for that year’s flu season six months in advance in order to have enough time to manufacture sufficient amounts of the vaccine. Or a vaccine for HIV, which still does not exist, largely due to the fact that HIV is very rapidly mutating, as well as that it can travel from host cell to host cell without entering the blood, escaping detection by antibodies. 

HIV and the flu exhibit rapid antigenic drift: their antigens are constantly making small changes, their genomes drifting. In antigenic drift, small mutations accumulate over time, mainly because when viruses are translated, they don’t use the same mechanisms for checking for errors that our bodies do. However, HIV and the flu exhibit antigenic shifts as well, meaning large, radical changes are made to the antigens. Typically, this happens when two strains of the same virus co-infect a host cell, and large portions of RNA end up getting switched from one virus to another. Zoonotic organisms cross species this way, as with swine flu and bird flu. The same applies to coronavirus, what we saw with SARS and now COVID. Both have been linked to transmission from animals. 

If we miss the chance for vaccination, instead of relying on our immune system to ward off viruses, our options are to rely on the antibodies produced by another’s immune system — plasma exchange — or to use medications aimed at viruses but not humans. Tamiflu (oseltamivir) inhibits neuraminidase, making it more difficult for influenza to bind to human cells and later be cleaved to infect others. Many nucleoside analogues are used — fake, nonfunctional versions of the products used to make DNA (though these can also affect our own cell replication). Different classes of HIV medications inhibit the action of those enzymes the virus brings with it: reverse transcriptase, protease, integrase. But a virus is a tough creature to kill, often only being suppressed, like HIV in the face of antiretroviral therapy, or hiding latent for decades to emerge when the immune system is compromised (like VZV, the virus that causes chicken pox and shingles).  

But I have a confession to make. I didn’t go back and rewatch Inception because of a vague nagging sensation I couldn’t identify, or a flash of scenes, as I claimed earlier. I had the inkling for this essay first: a link between viruses and Nolan’s concept of an idea, and that idea’s propagation in the mind. This inspiration led me back to Inception deliberately. To take notes on the plot and jot down quotes. Where did that spark come from? Was it from a previous viewing of the movie, though I hadn’t seen it for years? Was it from a post on Reddit, or a reference in a conversation I’d overheard? I don’t know. I’m not even sure when the spark first sputtered. And I’m forced to disagree with Nolan’s premise for Inception.  

The team must hide from Fischer that they were ever-present in his mind so that he believes the decision to dismantle his father’s company came solely from himself. This need for the mind to believe an idea is its own is why inception is so hard: “The subject’s mind can always trace the genesis of an idea. True inspiration is impossible to fake.” But the mind doesn’t care if an idea was self-generated. I was perfectly content to write this essay without being able to identify its underlying lineage. We see memes, internet sensations that “go viral” and happily pass them along. We are constantly building off the ideas of others and often don’t even know it, or care to know it.  

We have seen that political or ideologic extremism can be fueled by feedback loops of algorithms on the internet and especially social media. Any piece of seemingly contrary evidence can fuel doubts. The “wind” in the American flag planted on the moon without visible stars behind it, claimed inconsistencies in satellite photos of earth pointed out by members of the Flat Earth Society, abnormal stock trading patterns in the days leading up to 9/11. Viewed through a specific lens or a particular climate, anything can add fuel to the fire. 

As an article in The Journal of the American Medical Association points out regarding COVID conspiracy theories, “social media-fueled echo chambers amplify these theories, reinforcing false beliefs.” Notably, studies have shown that people can be “inoculated” against conspiracy theories by being presented with facts that negate misinformation prior to exposure to the misinformation itself. 

Furthermore, it’s way too oversimplified to predict how something will evolve. In the end, Cobb’s team does successfully plant the idea in Fischer’s head that his father would want him to be something different, to be his own man. But that seems far from a guarantee that this would lead to Fischer dissolving his family’s business, allowing Saito’s to thrive. Like the world, the mind is a complex place with innumerous ever-changing variables, any one of which could influence the progression of a concept. As they say, if a butterfly flaps its wings in Japan, it could cause a tornado in Texas. Nobody predicted the storming of the Capitol that stemmed immediately from Trump’s rally claiming voter fraud, but indirectly from months and years of propaganda. 

Cobb felt confident accepting Saito’s proposal, knows that inception is possible, because he performed it, albeit accidentally, on his wife Mal. She was the index case. While the two of them were stuck in a dreamworld, she came to believe she was in reality. She refused to leave. “She was possessed, by an idea.” The way to get her out, Cobb devised, was to convince her the dream wasn’t real. So, he planted that seed. Each dreamer carries a totem, a personalized object, that is unique. The totem is a reminder, physical proof, that they are dreaming. Mal’s object was a top — when spun in a dream, this top would never topple. Mal had lain the top down, not spinning, and locked it away. That she was in a dream was “a truth she had once known and chose to forget.” 

Cobb found Mal’s top, her totem, and set it spinning. Proof that she was dreaming. Cobb explains “I planted an idea, a simple little idea that would change everything.” Mal did come to realize she was dreaming. She agreed to leave the dream world and return to reality. The couple laid down with their necks on a railway as a train barreled towards them, causing their deaths in the dream world, and awoke in reality. What Cobb didn’t realize was the idea he’d planted would continue to grow in Mal, “like a cancer,” convincing her that the reality in which she awoke was also a dream. She again commits suicide. This time by jumping off a building. This time she didn’t wake up.   

Sometimes viruses do lead to the demise of the host. The immune response wasn’t strong enough, we didn’t have the right medications to get to it. Maybe it’s from the loss of CD4 cells, a subtype of T lymphocytes targeted by HIV, that then allows for opportunistic infections to take over and kill the host. Maybe it’s from swelling in the brain seen in a viral meningitis that eventually inhibits the basic functions needed to live. Maybe it’s from a potent immune response that causes the lungs to flood with inflammatory cells, rendering them no longer capable of delivering the oxygen the body requires. But this doesn’t do the virus any favors.  

If Fischer had died, he wouldn’t have been able to carry out whatever action the implanted seed leads him to. He almost did die and the team went to extraordinary lengths, risking their owns lives and sanities, to save him. The idea that dominated Mal died with her. If a Facebook user posted that everyone should quit Facebook and those who read it did, only a few people would carry out that action before the proposal exited Facebook alongside them. If someone is banned from a social media platform, they must find another medium to spread their gospel. 

The most successful viruses are those that keep the host alive, even well enough to go about their normal business, and expose others. The most successful viruses mutate frequently, making them difficult for the immune system to catch and medications to treat. We don’t really understand how viruses began, and likely don’t fully grasp the implications they’ve had on our planet and species. But undoubtedly those implications are massive The next time you feel fatigued, ask if it’s because your body is working hard to make copies of a virus. Or could it be that your immune system is busy fighting the virus off? Or both? The next time you perform an action or have an idea, try to trace where it came from. Is it fully from you? Is that even possible? Can it be trusted? 

After Mal commits suicide in reality, Cobb adopts her totem as his own. The spinning top. On my couch, as the last scene of Inception bore down on me, the sun now setting outside my shaded windows, I braced myself. I knew what was coming, the ambiguous closing scene. Maybe I’d pick up on something I’d missed before? A detail that would permit me to escape from the internet conjecture? The dream team wakes up at the end of their first-class journey. Fischer with no idea what’s happened, though something changed. Cobb has accomplished his goal. He’s back in the United States, back with his children. In the home he once shared with Mal, Cobb sets the top to spin on the kitchen table. The top spins. Spins. Spins. The top begins to wobble slightly. The screen cuts to black. •


Lindsay Ripley is an internal medicine physician and assistant professor in Dallas. Her literary work has appeared in D Magazine, The Journal of Graduate Medical Education, and on healthcare websites Doximity and KevinMD. She is currently working on an MFA in nonfiction creative writing and spends a lot of time thinking about movies.