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Five weird thought experiments to break your brain
Thought expriments are great tools, but do they always do what we want them to?
- Thought experiments are quite popular, though some get more time in the sun than others.
- While they are supposed to help guide our intuition to help solve difficult problems, some are a bit removed from reality.
- Can we trust the intuitions we have about problems set in sci-fi worlds or that postulate impossible monsters?
Despite the reported unpopularity of philosophy, its thought experiments are extremely popular tools for helping people understand how they look at the world. Famous examples, such as the Veil of Ignorance and the Trolley Problem, permeate popular culture, feature on memes, and help people clarify their thinking.
Not all thought experiments are created equal, though. Some of them are far less popular than others, some have fallen from being widely discussed to being historical curiosities, and others were always just restatements of Descartes.
A few of them, popular and unpopular, have pushed the limits of what a "good" thought experiment is. Philosopher and Big Think contributor Daniel Dennett suggests that many thought experiments venture into areas where we cannot have good intuitions, making them less than ideal experiments.
For example, while we can all think very clearly about the trolley problem—everything in it is straightforward enough to be grasped by everybody—an experiment that asks us to imagine sci-fi situations or the life choices of fantastic monsters might be too far out there to be effective.
Today, we'll look at five thought experiments that have been accused of being just a little too separated from reality to be useful. We'll consider what they're trying to shed light on, and review why they may or may not manage to do it.
The Swampman Cometh
"Suppose a man is out for a walk one day when a bolt of lightning disintegrates him. Simultaneously, a bolt of lightning strikes a marsh and causes a bunch of molecules to spontaneously rearrange into the same pattern that constituted that man a few moments ago. This 'Swampman' has an exact copy of the brain, memories, patterns of behavior as he did. It goes about its day, works, interacts with the man's friends and is otherwise indistinguishable from him."
Is the Swampman the same person as Davidson? When he refers to things he "remembers" seeing before, even though the Swampman never actually saw them, do his words mean anything? This experiment, combined with "The Ship of Theseus" causes people to wonder if teleportation through creating a copy of a person and then destroying the original actually "kills" the person being teleported.
Of course, we don't have teleportation yet, nor are there actual Swamp-people running around (Or are there!?!?!). While the questions raised by the Swampman are important ones, Dennett's warning is that we shouldn't be too quick to trust our intuition when the problem is so separated from anything we've ever encountered.
The Utility Monster
This thought experiment from Robert Nozick's defense of libertarianism "Anarchy, State, and Utopia" asks what we'd have to do if Utilitarianism is correct and we met something capable of much greater happiness than anybody else.
"Utilitarian theory is embarrassed by the possibility of utility monsters who get enormously greater gains in utility from any sacrifice of others than these others lose. For, unacceptably, the theory seems to require that we all be sacrificed in the monster's maw, in order to increase total utility."
If there was a utility monster that got a million times more joy out of everything than anybody else does, would we be obligated to give it everything it demanded to maximize the total happiness? Even if those demands cause suffering, but never enough to tip the ethical scales, elsewhere? If so, what does this mean for Utilitarianism as a moral theory?
At first, this experiment doesn't seem too bizarre. We all grasp the idea of somebody who gets more out of something than we do; this is just taking that idea to the extreme. The fundamental problem with this experiment was pointed out by philosopher Derek Parfit who argued that, while we are capable of imagining somebody who is happier than we are or who would get more out of something than we do, the idea of a creature that gets a million times more happiness out of things is impossible to imagine in a meaningful way.
How can we get useful insights into the problem if we can't hope to grasp how this monster interacts with the world? Because of this difficulty, Parfit rejected the problem.
Utilitarian philosopher and Big Think contributor Peter Singer accepts that if there were utility monsters there might be a problem for Utilitarianism, but, as he explained to The Nation, he finds the idea far-fetched. When posed the problem in the context of a billionaire owning a superyacht rather than donating money to fund medical treatments, he replied:
"We would have to assume that Larry Ellison actually has capacities for happiness that are vastly greater than anyone else's. Ellison's yacht cost $200 million, and if we assume that $400 can repair an obstetric fistula, that means that the suffering relieved by 500,000 obstetric fistula repairs is not greater than the happiness that Ellison gets from his yacht. That, I think, is not physically possible."
Continuing on the theme of bizarre thought experiments involving monsters, we have a strange reworking of Pascal's Wager involving a super-intelligent AI. It was created by a contributor to the website LessWrong named "Roko."
Given the length of the original post, I will summarize it here:
Imagine for a moment that humanity will someday create a hyper-powered artificial intelligence that is capable of solving all of the world's problems. It follows a form of utilitarian ethics and is trying to reduce human suffering as much as it can, which is a considerable amount. Given all the good it can do, it coming into existence, and doing so quickly, would substantially benefit humanity. Fully capable of simulating anything it wants, it then decides to take steps to punish those who knew about the good it could do but didn't help create it by torturing simulations of them.
Is it rational then to start donating a lot of money to those creating this super intelligence to avoid having it simulate and torture a copy of you in the future? This experiment gained a fair amount of notoriety online, and a name based on the creature that kills with its gaze, because by reading about it, you think about the monster and become a potential victim in the future, since now you know about it and might choose not to help create it.
Maybe I should have mentioned that part first. Oh well, so it goes.
As you might have realized, this experiment requires you to assume that we can reliably predict the behavior and motivations of a particular, ultra-intelligent AI that doesn't exist yet and may never exist. In terms of raw intelligence, this might be akin to asking a brainless starfish to predict how a human will behave one hundred years from now. While the experiment is said to have given some people nightmares, it isn't taken seriously by most people outside a small circle on the internet.
Plus, the long list of assumptions in the experiment includes that a simulation of you is actually "you" in a meaningful way. We have to solve the Swampman problem before we can agree on that point at all.
A surreal experiment by Judith Thomson that appeared in her famous essay "A Defense of Abortion." The essay is a series of arguments for the morality of abortion in certain circumstances through thought experiments. While some parts of it are quite famous, this section seems to avoid widespread discussion:
"Again, suppose it were like this: people-seeds drift about in the air like pollen, and if you open your windows, one may drift in and take root in your carpets or upholstery. You don't want children, so you fix up your windows with fine mesh screens, the very best you can buy. As can happen, however, and on very, very rare occasions does happen, one of the screens is defective; and a seed drifts in and takes root."
The question being, would it be acceptable to uproot the person-plant-fetus that gets in? Is it too much to ask that people live without cloth in their homes if they don't want people seeds to get in? How about never opening their doors or windows?
While this is supposed to be analogous to accidental pregnancy resulting from birth control failures, the downright bizarre nature of the thought experiment has been commented on by more than a few critics. Philosopher Kathleen Wilkes argued that it was too far removed from our reality to provide meaningful intuitions on abortion in her book "Real People."
After all, society would probably have very different ideas on what the right to life means if we came into the world because a bit of pollen landed on the carpet.
"We begin by supposing that elsewhere in the universe there is a planet exactly like Earth in virtually all aspects, which we refer to as "Twin Earth." (We should also suppose that the relevant surroundings are exactly the same as for Earth; it revolves around a star that appears to be exactly like our sun, and so on). On Twin Earth, there is a Twin equivalent of every person and thing here on Earth. The one difference between the two planets is that there is no water on Twin Earth. In its place there is a liquid that is superficially identical, but is chemically different, being composed not of H2O, but rather of some more complicated formula which we abbreviate as 'XYZ.' The Twin Earthlings who refer to their language as 'English' call XYZ 'water.' Finally, we set the date of our thought experiment to be several centuries ago, when the residents of Earth and Twin Earth would have no means of knowing that the liquids they called 'water' were H2O and XYZ respectively. The experience of people on Earth with water and that of those on Twin Earth with XYZ would be identical."
Do the Earthling (who Putnam named Oscar) and his twin (also named Oscar) mean the same thing when they say "water?" Their mental states are the same when they refer to it, but the object in question is physically different in each case. If the twins' statements don't mean the same thing, then we must admit that external factors play a role in defining terms external to the speaker, a stance dubbed "scientific externalism."
While this experiment is quite famous and has advanced a fair amount of debate, you can probably already see the difficulties some people have with it.
Philosopher Tyler Burge has argued that the whole experiment is flawed, as Earth Oscar refers to the concept of "H2O," while Twin Earth Oscar is referring to the concept of "XYZ." Dr. Burge argued that this means their mental states are different from the get-go. He also points out that the stuff flowing on Twin Earth isn't actually water, which might derail the whole thing.
For his part, Putnam criticized others for using thought experiments that require you to ignore specific ideas to arrive at the intended ones. In this experiment, with humans presumably still being 60 percent water, you'd have to imagine that changing what water is at the molecular level would not alter the beings thinking about the water in any meaningful way. He has also admitted that Dr. Burge's first critique is actually a very good one.
Surprisingly, Daniel Dennett has spent a fair amount of time discussing the content of the problem rather than on how strange the whole experiment is in the first place. It might go to show that philosophers love a good thought experiment, even if the results aren't directly applicable to the real world.
- Daniel Dennett Dissects a Bad Thought Experiment - Big Think ›
- What a Thought Experiment is All About - Big Think ›
- Seven thought experiments to make you question everything - Big ... ›
Why mega-eruptions like the ones that covered North America in ash are the least of your worries.
- The supervolcano under Yellowstone produced three massive eruptions over the past few million years.
- Each eruption covered much of what is now the western United States in an ash layer several feet deep.
- The last eruption was 640,000 years ago, but that doesn't mean the next eruption is overdue.
The end of the world as we know it
Panoramic view of Yellowstone National Park
Image: Heinrich Berann for the National Park Service – public domain
Of the many freak ways to shuffle off this mortal coil – lightning strikes, shark bites, falling pianos – here's one you can safely scratch off your worry list: an outbreak of the Yellowstone supervolcano.
As the map below shows, previous eruptions at Yellowstone were so massive that the ash fall covered most of what is now the western United States. A similar event today would not only claim countless lives directly, but also create enough subsidiary disruption to kill off global civilisation as we know it. A relatively recent eruption of the Toba supervolcano in Indonesia may have come close to killing off the human species (see further below).
However, just because a scenario is grim does not mean that it is likely (insert topical political joke here). In this case, the doom mongers claiming an eruption is 'overdue' are wrong. Yellowstone is not a library book or an oil change. Just because the previous mega-eruption happened long ago doesn't mean the next one is imminent.
Ash beds of North America
Ash beds deposited by major volcanic eruptions in North America.
Image: USGS – public domain
This map shows the location of the Yellowstone plateau and the ash beds deposited by its three most recent major outbreaks, plus two other eruptions – one similarly massive, the other the most recent one in North America.
The Huckleberry Ridge eruption occurred 2.1 million years ago. It ejected 2,450 km3 (588 cubic miles) of material, making it the largest known eruption in Yellowstone's history and in fact the largest eruption in North America in the past few million years.
This is the oldest of the three most recent caldera-forming eruptions of the Yellowstone hotspot. It created the Island Park Caldera, which lies partially in Yellowstone National Park, Wyoming and westward into Idaho. Ash from this eruption covered an area from southern California to North Dakota, and southern Idaho to northern Texas.
About 1.3 million years ago, the Mesa Falls eruption ejected 280 km3 (67 cubic miles) of material and created the Henry's Fork Caldera, located in Idaho, west of Yellowstone.
It was the smallest of the three major Yellowstone eruptions, both in terms of material ejected and area covered: 'only' most of present-day Wyoming, Colorado, Kansas and Nebraska, and about half of South Dakota.
The Lava Creek eruption was the most recent major eruption of Yellowstone: about 640,000 years ago. It was the second-largest eruption in North America in the past few million years, creating the Yellowstone Caldera.
It ejected only about 1,000 km3 (240 cubic miles) of material, i.e. less than half of the Huckleberry Ridge eruption. However, its debris is spread out over a significantly wider area: basically, Huckleberry Ridge plus larger slices of both Canada and Mexico, plus most of Texas, Louisiana, Arkansas, and Missouri.
This eruption occurred about 760,000 years ago. It was centered on southern California, where it created the Long Valley Caldera, and spewed out 580 km3 (139 cubic miles) of material. This makes it North America's third-largest eruption of the past few million years.
The material ejected by this eruption is known as the Bishop ash bed, and covers the central and western parts of the Lava Creek ash bed.
Mount St Helens
The eruption of Mount St Helens in 1980 was the deadliest and most destructive volcanic event in U.S. history: it created a mile-wide crater, killed 57 people and created economic damage in the neighborhood of $1 billion.
Yet by Yellowstone standards, it was tiny: Mount St Helens only ejected 0.25 km3 (0.06 cubic miles) of material, most of the ash settling in a relatively narrow band across Washington State and Idaho. By comparison, the Lava Creek eruption left a large swathe of North America in up to two metres of debris.
The difference between quakes and faults
The volume of dense rock equivalent (DRE) ejected by the Huckleberry Ridge event dwarfs all other North American eruptions. It is itself overshadowed by the DRE ejected at the most recent eruption at Toba (present-day Indonesia). This was one of the largest known eruptions ever and a relatively recent one: only 75,000 years ago. It is thought to have caused a global volcanic winter which lasted up to a decade and may be responsible for the bottleneck in human evolution: around that time, the total human population suddenly and drastically plummeted to between 1,000 and 10,000 breeding pairs.
Image: USGS – public domain
So, what are the chances of something that massive happening anytime soon? The aforementioned mongers of doom often claim that major eruptions occur at intervals of 600,000 years and point out that the last one was 640,000 years ago. Except that (a) the first interval was about 200,000 years longer, (b) two intervals is not a lot to base a prediction on, and (c) those intervals don't really mean anything anyway. Not in the case of volcanic eruptions, at least.
Earthquakes can be 'overdue' because the stress on fault lines is built up consistently over long periods, which means quakes can be predicted with a relative degree of accuracy. But this is not how volcanoes behave. They do not accumulate magma at constant rates. And the subterranean pressure that causes the magma to erupt does not follow a schedule.
What's more, previous super-eruptions do not necessarily imply future ones. Scientists are not convinced that there ever will be another big eruption at Yellowstone. Smaller eruptions, however, are much likelier. Since the Lava Creek eruption, there have been about 30 smaller outbreaks at Yellowstone, the last lava flow being about 70,000 years ago.
As for the immediate future (give or take a century): the magma chamber beneath Yellowstone is only 5 percent to 15 percent molten. Most scientists agree that is as un-alarming as it sounds. And that its statistically more relevant to worry about death by lightning, shark, or piano.
Strange Maps #1041
Got a strange map? Let me know at firstname.lastname@example.org.
Measuring a person's movements and poses, smart clothes could be used for athletic training, rehabilitation, or health-monitoring.
In recent years there have been exciting breakthroughs in wearable technologies, like smartwatches that can monitor your breathing and blood oxygen levels.
But what about a wearable that can detect how you move as you do a physical activity or play a sport, and could potentially even offer feedback on how to improve your technique?
And, as a major bonus, what if the wearable were something you'd actually already be wearing, like a shirt of a pair of socks?
That's the idea behind a new set of MIT-designed clothing that use special fibers to sense a person's movement via touch. Among other things, the researchers showed that their clothes can actually determine things like if someone is sitting, walking, or doing particular poses.
The group from MIT's Computer Science and Artificial Intelligence Lab (CSAIL) says that their clothes could be used for athletic training and rehabilitation. With patients' permission, they could even help passively monitor the health of residents in assisted-care facilities and determine if, for example, someone has fallen or is unconscious.
The researchers have developed a range of prototypes, from socks and gloves to a full vest. The team's "tactile electronics" use a mix of more typical textile fibers alongside a small amount of custom-made functional fibers that sense pressure from the person wearing the garment.
According to CSAIL graduate student Yiyue Luo, a key advantage of the team's design is that, unlike many existing wearable electronics, theirs can be incorporated into traditional large-scale clothing production. The machine-knitted tactile textiles are soft, stretchable, breathable, and can take a wide range of forms.
"Traditionally it's been hard to develop a mass-production wearable that provides high-accuracy data across a large number of sensors," says Luo, lead author on a new paper about the project that is appearing in this month's edition of Nature Electronics. "When you manufacture lots of sensor arrays, some of them will not work and some of them will work worse than others, so we developed a self-correcting mechanism that uses a self-supervised machine learning algorithm to recognize and adjust when certain sensors in the design are off-base."
The team's clothes have a range of capabilities. Their socks predict motion by looking at how different sequences of tactile footprints correlate to different poses as the user transitions from one pose to another. The full-sized vest can also detect the wearers' pose, activity, and the texture of the contacted surfaces.
The authors imagine a coach using the sensor to analyze people's postures and give suggestions on improvement. It could also be used by an experienced athlete to record their posture so that beginners can learn from them. In the long term, they even imagine that robots could be trained to learn how to do different activities using data from the wearables.
"Imagine robots that are no longer tactilely blind, and that have 'skins' that can provide tactile sensing just like we have as humans," says corresponding author Wan Shou, a postdoc at CSAIL. "Clothing with high-resolution tactile sensing opens up a lot of exciting new application areas for researchers to explore in the years to come."
The paper was co-written by MIT professors Antonio Torralba, Wojciech Matusik, and Tomás Palacios, alongside PhD students Yunzhu Li, Pratyusha Sharma, and Beichen Li; postdoc Kui Wu; and research engineer Michael Foshey.
The work was partially funded by Toyota Research Institute.
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.