How to Think Like a Philosopher, with Daniel Dennett


Daniel Dennett: An Introduction to Intuition Pumps

Daniel Dennett, one of the best-known living philosophers and a professor at Tufts University, believes it's time to unmask the philosopher's art and make thought experimentation accessible to a wider audience. "How to Think Like a Philosopher," Dennett's five-part workshop, is a journey into the labyrinthine mind games played by Dennett and his colleagues


For the more utilitarian-minded, these are mental practices that will improve your ability to focus and think both rationally and creatively.

How to Think Like a Philosopher takes you on a guided tour through many of Dennett's favorite "tools for thinking." Along the way, he teaches you:

- The value of "intuition pumps" (or thought experiments) and how to use them.

- How to recognize common rhetorical tricks for manufacturing consent.

- Why free will doesn't always imply unpredictability.

- How to "twiddle the knobs" of thought, exploring alternatives and the conclusions they lead to.

Daniel Dennett: Stop Telling People They Don't Have Free Will

Philosopher Daniel Dennett takes issue with neuroscientists who argue that humans don't have free will. In this video, Dennett demonstrates an intuition pump (or thought experiment) featuring a "nefarious neurosurgeon" who lies to a patient with obsessive compulsive disorder. Dennett argues that telling people that free will is an illusion makes them less concerned about the negative implications of their actions.

Daniel Dennett: How Does the Brain Store Beliefs?

What if beliefs could be surgically inserted into a patient's brain? This is the basis of one of philosopher Daniel Dennett's thought experiments in exploration of how the brain represents beliefs. Dennett argues that individual beliefs are part of broader idea systems and that they couldn't possibly be stored like a library of belief sentences.

Daniel Dennett Dissects a Bad Thought Experiment

Schrödinger's cat. The prisoner's dilemma. The trolley problem. These are brand names as much as they're philosophical thought experiments. Philosopher Daniel Dennett explains the importance of concocting an attractive package in which to wrap your argument. At the same time, Dennett warns that this can backfire and, to demonstrate, he dissects one of his "favorite bad thought experiments," an investigation of free will based on the sci-fi film "The Boys From Brazil."

Daniel Dennett: How Life is Like a Game of Rock-Paper-Scissors

Philosopher Daniel Dennett dissects the strategies behind the game rock-paper-scissors and determines that randomness/indeterminacy is the optimal strategy. The best way to avoid being detected by your opponent is to rely on a random determination of which move to use. Some people have jumped to the conclusion that maintaining a sense of indeterminacy is optimal for living a life in which one is always in competition with outside forces. While perfect indeterminacy would be an asset for playing rock-paper-scissors, Dennett argues it's not really that necessary in other most other aspects of life.

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  • The weirdness of quantum theory flies in the face of what we experience in our everyday lives.
  • Quantum weirdness quickly created a split in the physics community, each side championed by a giant: Albert Einstein and Niels Bohr.
  • As two recent books espousing opposing views show, the debate still rages on nearly a century afterward. Each "resolution" comes with a high price tag.

Albert Einstein and Niels Bohr, two giants of 20th century science, espoused very different worldviews.

To Einstein, the world was ultimately rational. Things had to make sense. They should be quantifiable and expressible through a logical chain of cause-and-effect interactions, from what we experience in our everyday lives all the way to the depths of reality. To Bohr, we had no right to expect any such order or rationality. Nature, at its deepest level, need not follow any of our expectations of well-behaved determinism. Things could be weird and non-deterministic, so long as they became more like what we expect when we traveled from the world of atoms to our world of trees, frogs, and cars. Bohr divided the world into two realms, the familiar classical world, and the unfamiliar quantum world. They should be complementary to one another but with very different properties.

The two scientists spent decades arguing about the impact of quantum physics on the nature of reality. Each had groups of physicists as followers, all of them giants of their own. Einstein's group of quantum weirdness deniers included quantum physics pioneers Max Planck, Louis de Broglie, and Erwin Schrödinger, while Bohr's group had Werner Heisenberg (of uncertainty principle fame), Max Born, Wolfgang Pauli, and Paul Dirac.

Almost a century afterward, the debate rages on.

Einstein vs. Bohr, Redux

Two books — one authored by Sean Carroll and published last fall and another published very recently and authored by Carlo Rovelli — perfectly illustrate how current leading physicists still cannot come to terms with the nature of quantum reality. The opposing positions still echo, albeit with many modern twists and experimental updates, the original Einstein-Bohr debate.

Albert Einstein and Niels Bohr, two giants of 20th century science, espoused very different worldviews.

I summarized the ongoing dispute in my book The Island of Knowledge: Are the equations of quantum physics a computational tool that we use to make sense of the results of experiments (Bohr), or are they supposed to be a realistic representation of quantum reality (Einstein)? In other words, are the equations of quantum theory the way things really are or just a useful map?

Einstein believed that quantum theory, as it stood in the 1930s and 1940s, was an incomplete description of the world of the very small. There had to be an underlying level of reality, still unknown to us, that made sense of all its weirdness. De Broglie and, later, David Bohm, proposed an extension of the quantum theory known as hidden variable theory that tried to fill in the gap. It was a brilliant attempt to appease the urge Einstein and his followers had for an orderly natural world, predictable and reasonable. The price — and every attempt to deal with the problem of figuring out quantum theory has a price tag — was that the entire universe had to participate in determining the behavior of every single electron and all other quantum particles, implicating the existence of a strange cosmic order.

Later, in the 1960s, physicist John Bell proved a theorem that put such ideas to the test. A series of remarkable experiments starting in the 1970s and still ongoing have essentially disproved the de Broglie-Bohm hypothesis, at least if we restrict their ideas to what one would call "reasonable," that is, theories that have local interactions and causes. Omnipresence — what physicists call nonlocality — is a hard pill to swallow in physics.

Credit: Public domain

Yet, the quantum phenomenon of superposition insists on keeping things weird. Here's one way to picture quantum superposition. In a kind of psychedelic dream state, imagine that you had a magical walk-in closet filled with identical shirts, the only difference between them being their color. What's magical about this closet? Well, as you enter this closet, you split into identical copies of yourself, each wearing a shirt of a different color. There is a you wearing a blue shirt, another a red, another a white, etc., all happily coexisting. But as soon as you step out of the closet or someone or something opens the door, only one you emerges, wearing a single shirt. Inside the closet, you are in a superposition state with your other selves. But in the "real" world, the one where others see you, only one copy of you exists, wearing a single shirt. The question is whether the inside superposition of the many yous is as real as the one you that emerges outside.

To Einstein, the world was ultimately rational... To Bohr, we had no right to expect any such order or rationality.

The (modern version of the) Einstein team would say yes. The equations of quantum physics must be taken as the real description of what's going on, and if they predict superposition, so be it. The so-called wave function that describes this superposition is an essential part of physical reality. This point is most dramatically exposed by the many-worlds interpretation of quantum physics, espoused in Carroll's book. For this interpretation, reality is even weirder: the closet has many doors, each to a different universe. Once you step out, all of your copies step out together, each into a parallel universe. So, if I happen to see you wearing a blue shirt in this universe, in another, I'll see you wearing a red one. The price tag for the many-worlds interpretation is to accept the existence of an uncountable number of non-communicating parallel universes that enact all possibilities from a superstition state. In a parallel universe, there was no COVID-19 pandemic. Not too comforting.

Bohm's team would say take things as they are. If you stepped out of the closet and someone saw you wearing a shirt of a given color, then this is the one. Period. The weirdness of your many superposing selves remains hidden in the quantum closet. Rovelli defends his version of this worldview, called relational interpretation, in which events are defined by the interactions between the objects involved, be them observers or not. In this example, the color of your shirt is the property at stake, and when I see it, I am entangled with this specific shirt of yours. It could have been another color, but it wasn't. As Rovelli puts it, "Entanglement… is the manifestation of one object to another, in the course of an interaction, in which the properties of the objects become actual." The price to pay here is to give up the hope of ever truly understanding what goes on in the quantum world. What we measure is what we get and all we can say about it.

What should we believe?

Both Carroll and Rovelli are master expositors of science to the general public, with Rovelli being the more lyrical of the pair.

There is no resolution to be expected, of course. I, for one, am more inclined to Bohr's worldview and thus to Rovelli's, although the interpretation I am most sympathetic to, called QBism, is not properly explained in either book. It is much closer in spirit to Rovelli's, in that relations are essential, but it places the observer on center stage, given that information is what matters in the end. (Although, as Rovelli acknowledges, information is a loaded word.)

We create theories as maps for us human observers to make sense of reality. But in the excitement of research, we tend to forget the simple fact that theories and models are not nature but our representations of nature. Unless we nurture hopes that our theories are really how the world is (the Einstein camp) and not how we humans describe it (the Bohr camp), why should we expect much more than this?

  • Researchers find a correlation between pupil size and differences in cognitive ability.
  • The larger the pupil, the higher the intelligence.
  • The explanation for why this happens lies within the brain, but more research is needed.

What can you tell by looking into someone's eyes? You can spot a glint of humor, signs of tiredness, or maybe that they don't like something or someone.

But outside of assessing an emotional state, a person's eyes may also provide clues about their intelligence, suggests new research. A study carried out at the Georgia Institute of Technology shows that pupil size is "closely related" to differences in intelligence between individuals.

The scientists found that larger pupils may be connected to higher intelligence, as demonstrated by tests that gauged reasoning skills, memory, and attention. In fact, the researchers claim that the relationship of intelligence to pupil size is so pronounced, that it came across their previous two studies as well and can be spotted just with your naked eyes, without any additional scientific instruments. You should be able to tell who scored the highest or the lowest on the cognitive tests just by looking at them, say the researchers.

The pupil-IQ link

The connection was first noticed across memory tasks, looking at pupil dilations as signs of mental effort. The studies involved more than 500 people aged 18 to 35 from the Atlanta area. The subjects' pupil sizes were measured by eye trackers, which use a camera and a computer to capture light reflecting off the pupil and cornea. As the scientists explained in Scientific American, pupil diameters range from two to eight millimeters. To determine average pupil size, they took measurements of the pupils at rest when the participants were staring at a blank screen for a few minutes.

Another part of the experiment involved having the subjects take a series of cognitive tests that evaluated "fluid intelligence" (the ability to reason when confronted with new problems), "working memory capacity" (how well people could remember information over time), and "attention control" (the ability to keep focusing attention even while being distracted). An example of the latter involves a test that attempts to divert a person's focus on a disappearing letter by showing a flickering asterisk on another part of the screen. If a person pays too much attention to the asterisk, they might miss the letter.

The conclusions of the research were that having a larger baseline pupil size was related to greater fluid intelligence, having more attention control, and even greater working memory capacity, although to a smaller extent. In an email exchange with Big Think, author Jason Tsukahara pointed out, "It is important to consider that what we find is a correlation — which should not be confused with causation."

The researchers also found that pupil size seemed to decrease with age. Older people had more constricted pupils but when the scientists standardized for age, the pupil-size-to-intelligence connection still remained.

Why are pupils linked to intelligence?

The connection between pupil size and IQ likely resides within the brain. Pupil size has been previously connected to the locus coeruleus, a part of the brain that's responsible for synthesizing the hormone and neurotransmitter norepinephrine (noradrenaline), which mobilizes the brain and body for action. Activity in the locus coeruleus affects our perception, attention, memory, and learning processes.

As the authors explain, this region of the brain "also helps maintain a healthy organization of brain activity so that distant brain regions can work together to accomplish challenging tasks and goals." Because it is so important, loss of function in the locus coeruleus has been linked to conditions like Alzheimer's disease, Parkinson's, clinical depression, and attention deficit hyperactivity disorder (ADHD).

The researchers hypothesize that people who have larger pupils while in a restful state, like staring at a blank computer screen, have "greater regulation of activity by the locus coeruleus." This leads to better cognitive performance. More research is necessary, however, to truly understand why having larger pupils is related to higher intelligence.

In an email to Big Think, Tsukahara shared, "If I had to speculate, I would say that it is people with greater fluid intelligence that develop larger pupils, but again at this point we only have correlational data."

Do other scientists believe this?

As the scientists point out in the beginning of their paper, their conclusions are controversial and, so far, other researchers haven't been able to duplicate their results. The research team addresses this criticism by explaining that other studies had methodological issues and examined only memory capacity but not fluid intelligence, which is what they measured.

  • Conspiracy theories exist on a spectrum, from plausible and mainstream to fringe and unpopular.
  • It's very rare to find someone who only believes in one conspiracy theory. They generally believe in every conspiracy theory that's less extreme than their favorite one.
  • To some extent, we are all conspiracy theorists.

The following is an excerpt from the book Escaping the Rabbit Hole by Mick West. It is reprinted with permission from the author.

If you want to understand how people fall for conspiracy theories, and if you want to help them, then you have to understand the conspiracy universe. More specifically, you need to know where their favorite theories are on the broader spectrum of conspiracies.

What type of person falls for conspiracy theories? What type of person would think that the World Trade Center was a controlled demolition, or that planes are secretly spraying chemicals to modify the climate, or that nobody died at Sandy Hook, or that the Earth is flat? Are these people crazy? Are they just incredibly gullible? Are they young and impressionable? No, in fact the range of people who believe in conspiracy theories is simply a random slice of the general population.

There's a conspiracy theory for everyone, and hence very few people are immune.

Many dismiss conspiracy theorists as a bunch of crazy people, or a bunch of stupid people, or a bunch of crazy stupid people. Yet in many ways the belief in a conspiracy theory is as American as apple pie, and like apple pie it comes in all kinds of varieties, and all kinds of normal people like to consume it.

My neighbor down the road is a conspiracy theorist. Yet he's also an engineer, retired after a successful career. I've had dinner at his house, and yet he's a believer in chemtrails, and I'm a chemtrail debunker. It's odd; he even told me after a few glasses of wine that he thinks I'm being paid to debunk chemtrails. He thought this because he googled my name and found some pages that said I was a paid shill. Since he's a conspiracy theorist he tends to trust conspiracy sources more than mainstream sources, so he went with that.

I've met all kinds of conspiracy theorists. At a chemtrails convention I attended there was pretty much the full spectrum. There were sensible and intelligent older people who had discovered their conspiracy anything from a few months ago to several decades ago. There were highly eccentric people of all ages, including one old gentleman with a pyramid attached to his bike. There were people who channeled aliens, and there were people who were angry that the alien-channeling people were allowed in. There were young people itching for a revolution. There were well-read intellectuals who thought there was a subtle system of persuasion going on in the evening news, and there were people who genuinely thought they were living in a computer simulation.

There's such a wide spectrum of people who believe in conspiracy theories because the spectrum of conspiracy theories itself is very wide. There's a conspiracy theory for everyone, and hence very few people are immune.

The Mainstream and the Fringe

One unfortunate problem with the term "conspiracy theory" is that it paints with a broad brush. It's tempting to simply divide people up into "conspiracy theorists" and "regular people" — to have tinfoil-hat-wearing paranoids on one side and sensible folk on the other. But the reality is that we are all conspiracy theorists, one way or another. We all know that conspiracies exist; we all suspect people in power of being involved in many kinds of conspiracies, even if it's only something as banal as accepting campaign contributions to vote a certain way on certain types of legislation.

It's also tempting to simply label conspiracy theories as either "mainstream" or "fringe." Journalist Paul Musgrave referenced this dichotomy when he wrote in the Washington Post:

Less than two months into the administration, the danger is no longer that Trump will make conspiracy thinking mainstream. That has already come to pass.

Musgrave obviously does not mean that shape-shifting lizard overlords have become mainstream. Nor does he mean that flat Earth, chemtrails, or even 9/11 truth are mainstream. What he's really talking about is a fairly small shift in a dividing line on the conspiracy spectrum. Most fringe conspiracy theories remain fringe, most mainstream theories remain mainstream. But, Musgrave argues, there's been a shift that's allowed the bottom part of the fringe to enter into the mainstream. Obama being a Kenyan was thought by many to be a silly conspiracy theory, something on the fringe. But if the president of the United States (Trump) keeps bringing it up, then it moves more towards the mainstream.

Both conspiracy theories and conspiracy theorists exist on a spectrum. If we are to communicate effectively with a conspiracy-minded friend we need to get some perspective on the full range of that spectrum, and where our friend's personal blend of theories fit into it.

It's very rare to find someone who only believes in one conspiracy theory. They generally believe in every conspiracy theory that's less extreme than their favorite one.

There are several ways we can classify a conspiracy theory: how scientific is it? How many people believe in it? How plausible is? But one I'm going use is a somewhat subjective measure of how extreme the theory is. I'm going to rank them from 1 to 10, with 1 being entirely mainstream to 10 being the most obscure extreme fringe theory you can fathom.

This extremeness spectrum is not simply a spectrum of reasonableness or scientific plausibility. Being extreme is being on the fringe, and fringe simply denotes the fact that it's an unusual interpretation and is restricted to a small number of people. A belief in religious supernatural occurrences (like miracles) is a scientifically implausible belief, and yet it is not considered particularly fringe.

Let's start with a simple list of actual conspiracy theories. These are ranked by extremeness in their most typical manifestation, but in reality, the following represent topics that can span several points on the scale, or even the entire scale.

  1. Big Pharma: The theory that pharmaceutical companies conspire to maximize profit by selling drugs that people do not actually need
  2. Global Warming Hoax: The theory that climate change is not caused by man-made carbon emissions, and that there's some other motive for claiming this
  3. JFK: The theory that people in addition to Lee Harvey Oswald were involved in the assassination of John F. Kennedy
  4. 9/11 Inside Job: The theory that the events of 9/11 were arranged by elements within the US government
  5. Chemtrails: The theory that the trails left behind aircraft are part of a secret spraying program
  6. False Flag Shootings: The theory that shootings like Sandy Hook and Las Vegas either never happened or were arranged by people in power
  7. Moon Landing Hoax: The theory that the Moon landings were faked in a movie studio
  8. UFO Cover-Up: The theory that the US government has contact with aliens or crashed alien crafts and is keeping it secret
  9. Flat Earth: The theory that the Earth is flat, but governments, business, and scientists all pretend it is a globe
  10. Reptile Overlords: The theory that the ruling classes are a race of shape-shifting trans-dimensional reptiles

If your friend subscribes to one of these theories you should not assume they believe in the most extreme version. They could be anywhere within a range. The categories are both rough and complex, and while some are quite narrow and specific, others encapsulate a wide range of variants of the theory that might go nearly all the way from a 1 to a 10. The position on the fringe conspiracy spectrum instead gives us a rough reference point for the center of the extent of the conspiracy belief.

Credit: "Escaping the Rabbit Hole" by Mick West

Figure 3 is an illustration (again, somewhat subjective) of the extents of extremeness of the conspiracy theories listed. For some of them the ranges are quite small. Flat Earth and Reptile Overlords are examples of theories that exist only at the far end of the spectrum. It's simply impossible to have a sensible version of the Flat Earth theory due to the fact that the Earth is actually round.

Similarly, there exist theories at the lower end of the spectrum that are fairly narrow in scope. A plot by pharmaceutical companies to maximize profits is hard (but not impossible) to make into a more extreme version.

Other theories are broader in scope. The 9/11 Inside Job theory is the classic example where the various theories go all the way from "they lowered their guard to allow some attack to happen," to "the planes were holograms; the towers were demolished with nuclear bombs." The chemtrail theory also has a wide range, from "additives to the fuel are making contrails last longer" to "nano-machines are being sprayed to decimate the population."

There's also overlapping relationships between the theories. chemtrails might be spraying poison to help big pharma sell more drugs. JFK might have been killed because he was going to reveal that UFOs were real. Fake shootings might have been arranged to distract people from any of the other theories. The conspiracy theory spectrum is continuous and multi-dimensional.

Don't immediately pigeonhole your friend if they express some skepticism about some aspect of the broader theories. For example, having some doubts about a few pieces from a Moon-landing video does not necessarily mean that they think we never went to the Moon, it could just mean that they think a few bits of the footage were mocked up for propaganda purposes. Likewise, if they say we should question the events of 9/11, it does not necessarily mean that they think the Twin Towers were destroyed with explosives, it could just mean they think elements within the CIA helped the hijackers somehow.

Understanding where your friend is on the conspiracy spectrum is not about which topics he is interested in, it's about where he draws the line.

The Demarcation Line

While conspiracy theorists might individually focus on one particular theory, like 9/11 or chemtrails, it's very rare to find someone who only believes in one conspiracy theory. They generally believe in every conspiracy theory that's less extreme than their favorite one.

In practical terms this means that if someone believes in the chemtrail theory they will also believe that 9/11 was an inside job involving controlled demolition, that Lee Harvey Oswald was just one of several gunmen, and that global warming is a big scam.

The general conspiracy spectrum is complex, with individual theory categories spread out in multiple ways. But for your friend, an individual, they have an internal version of this scale, one that is much less complex. For the individual the conspiracy spectrum breaks down into two sets of beliefs — the reasonable and the ridiculous. Conspiracists, especially those who have been doing it for a while, make increasingly precise distinctions about where they draw the line.

The drawing of such dividing lines is called "demarcation." In philosophy there's a classical problem called the "demarcation problem," which is basically where you draw the line between science and non-science. Conspiracists have a demarcation line on their own personal version of the conspiracy spectrum. On one side of the line there's science and reasonable theories they feel are probably correct. On the other side of the line there's non-science, gibberish, propaganda, lies, and disinformation.

Credit: "Escaping the Rabbit Hole" by Mick West

    I have a line of demarcation (probably around 1.5), you have one, your friend has a line. We all draw the line in different places.

    The way an elephant manipulates its trunk to eat and drink could lead to better robots, researchers say.


    Elephants dilate their nostrils to create more space in their trunks, allowing them to store up to 5.5 liters (1.45 gallons) of water, according to their new study.

    They can also suck up three liters (0.79 gallons) per second—a speed 30 times faster than a human sneeze (150 meters per second/330 mph), the researchers found.

    The researchers wanted to better understand the physics of how elephants use their trunks to move and manipulate air, water, food, and other objects. They also wanted to learn if the mechanics could inspire the creation of more efficient robots that use air motion to hold and move things.


    A close up of an elephant's Photo by David Clode on Unsplash

    While octopuses use jets of water to propel themselves and archer fish shoot water above the surface to catch insects, elephants are the only animals able to use suction both on land and underwater.

    "An elephant eats about 400 pounds of food a day, but very little is known about how they use their trunks to pick up lightweight food and water for 18 hours, every day," says lead author Andrew Schulz, a mechanical engineering PhD student at the Georgia Institute of Technology. "It turns out their trunks act like suitcases, capable of expanding when necessary."

    Sucking up tortilla chips without breaking them

    Schulz and his colleagues worked with veterinarians at Zoo Atlanta, studying elephants as they ate various foods. For large rutabaga cubes, for example, the animal grabbed and collected them. It sucked up smaller cubes and made a loud vacuuming sound, like the sound of a person slurping noodles, before transferring the vegetables to its mouth.

    To learn more about suction, the researchers gave elephants a tortilla chip and measured the applied force. Sometimes the animal pressed down on the chip and breathed in, suspending the chip on the tip of its trunk without breaking it, similar to a person inhaling a piece of paper onto their mouth. Other times the elephant applied suction from a distance, drawing the chip to the edge of its trunk.

    Elephants inhale at speeds comparable to Japan's 300 mph bullet trains.

    "An elephant uses its trunk like a Swiss Army knife," says David Hu, Schulz's advisor and a professor in Georgia Tech's School of Mechanical Engineering. "It can detect scents and grab things. Other times it blows objects away like a leaf blower or sniffs them in like a vacuum."

    By watching elephants inhale liquid from an aquarium, the team was able to time the durations and measure volume. In just 1.5 seconds, the trunk sucked up 3.7 liters (just shy of 1 gallon), the equivalent of 20 toilets flushing simultaneously.

    Soft robots and elephant conservation

    The researchers used an ultrasonic probe to take trunk wall measurements and see how the trunk's inner muscles work. By contracting those muscles, the animal dilates its nostrils up to 30%. This decreases the thickness of the walls and expands nasal volume by 64%.

    "At first it didn't make sense: an elephant's nasal passage is relatively small and it was inhaling more water than it should," Schulz says. "It wasn't until we saw the ultrasonographic images and watched the nostrils expand that we realized how they did it. Air makes the walls open, and the animal can store far more water than we originally estimated."

    Based on the pressures applied, Schulz and the team suggest that elephants inhale at speeds comparable to Japan's 300-mph bullet trains.

    Schulz says these unique characteristics have applications in soft robotics and conservation efforts.

    "By investigating the mechanics and physics behind trunk muscle movements, we can apply the physical mechanisms—combinations of suction and grasping—to find new ways to build robots," Schulz says.

    "In the meantime, the African elephant is now listed as endangered because of poaching and loss of habitat. Its trunk makes it a unique species to study. By learning more about them, we can learn how to better conserve elephants in the wild."

    The paper appears in the Journal of the Royal Society Interface. The US Army Research Laboratory and the US Army Research Office 294 Mechanical Sciences Division, Complex Dynamics and Systems Program, funded the work. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the view of the sponsoring agency.

    Source: Georgia Tech

    Original Study DOI: 10.1098/rsif.2021.0215

    Reprinted with permission of Futurity. Read the original article.

    At the age of 16, when Tony Kofi was an apprentice builder living in Nottingham, he fell from the third story of a building. Time seemed to slow down massively, and he saw a complex series of images flash before his eyes.


    As he described it, “In my mind's eye I saw many, many things: children that I hadn't even had yet, friends that I had never seen but are now my friends. The thing that really stuck in my mind was playing an instrument". Then Tony landed on his head and lost consciousness.

    When he came to at the hospital, he felt like a different person and didn't want to return to his previous life. Over the following weeks, the images kept flashing back into his mind. He felt that he was “being shown something" and that the images represented his future.

    Later, Tony saw a picture of a saxophone and recognized it as the instrument he'd seen himself playing. He used his compensation money from the accident to buy one. Now, Tony Kofi is one of the UK's most successful jazz musicians, having won the BBC Jazz awards twice, in 2005 and 2008.

    Though Tony's belief that he saw into his future is uncommon, it's by no means uncommon for people to report witnessing multiple scenes from their past during split-second emergency situations. After all, this is where the phrase “my life flashed before my eyes" comes from.

    But what explains this phenomenon? Psychologists have proposed a number of explanations, but I'd argue the key to understanding Tony's experience lies in a different interpretation of time itself.

    When life flashes before our eyes

    The experience of life flashing before one's eyes has been reported for well over a century. In 1892, a Swiss geologist named Albert Heim fell from a precipice while mountain climbing. In his account of the fall, he wrote is was “as if on a distant stage, my whole past life [was] playing itself out in numerous scenes".

    More recently, in July 2005, a young woman called Gill Hicks was sitting near one of the bombs that exploded on the London Underground. In the minutes after the accident, she hovered on the brink of death where, as she describes it: “my life was flashing before my eyes, flickering through every scene, every happy and sad moment, everything I have ever done, said, experienced".

    In some cases, people don't see a review of their whole lives, but a series of past experiences and events that have special significance to them.

    Explaining life reviews

    Perhaps surprisingly, given how common it is, the “life review experience" has been studied very little. A handful of theories have been put forward, but they're understandably tentative and rather vague.

    For example, a group of Israeli researchers suggested in 2017 that our life events may exist as a continuum in our minds, and may come to the forefront in extreme conditions of psychological and physiological stress.

    Another theory is that, when we're close to death, our memories suddenly “unload" themselves, like the contents of a skip being dumped. This could be related to “cortical disinhibition" – a breaking down of the normal regulatory processes of the brain – in highly stressful or dangerous situations, causing a “cascade" of mental impressions.

    But the life review is usually reported as a serene and ordered experience, completely unlike the kind of chaotic cascade of experiences associated with cortical disinhibition. And none of these theories explain how it's possible for such a vast amount of information – in many cases, all the events of a person's life – to manifest themselves in a period of a few seconds, and often far less.

    Thinking in 'spatial' time

    An alternative explanation is to think of time in a “spatial" sense. Our commonsense view of time is as an arrow that moves from the past through the present towards the future, in which we only have direct access to the present. But modern physics has cast doubt on this simple linear view of time.

    Indeed, since Einstein's theory of relativity, some physicists have adopted a “spatial" view of time. They argue we live in a static “block universe" in which time is spread out in a kind of panorama where the past, the present and the future co-exist simultaneously.

    The modern physicist Carlo Rovelli – author of the best-selling The Order of Time – also holds the view that linear time doesn't exist as a universal fact. This idea reflects the view of the philosopher Immanuel Kant, who argued that time is not an objectively real phenomenon, but a construct of the human mind.

    This could explain why some people are able to review the events of their whole lives in an instant. A good deal of previous research – including my own – has suggested that our normal perception of time is simply a product of our normal state of consciousness.

    In many altered states of consciousness, time slows down so dramatically that seconds seem to stretch out into minutes. This is a common feature of emergency situations, as well as states of deep meditation, experiences on psychedelic drugs and when athletes are “in the zone".

    The limits of understanding

    But what about Tony Kofi's apparent visions of his future? Did he really glimpse scenes from his future life? Did he see himself playing the saxophone because somehow his future as a musician was already established?

    There are obviously some mundane interpretations of Tony's experience. Perhaps, for instance, he became a saxophone player simply because he saw himself playing it in his vision. But I don't think it's impossible that Tony did glimpse future events.

    If time really does exist in a spatial sense – and if it's true that time is a construct of the human mind – then perhaps in some way future events may already be present, just as past events are still present.

    Admittedly, this is very difficult to make sense of. But why should everything make sense to us? As I have suggested in a recent book, there must be some aspects of reality that are beyond our comprehension. After all, we're just animals, with a limited awareness of reality. And perhaps more than any other phenomenon, this is especially true of time.The Conversation

    Steve Taylor, Senior Lecturer in Psychology, Leeds Beckett University

    This article is republished from The Conversation under a Creative Commons license. Read the original article.