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Seven thought experiments that will make you question everything
Philosophers love to use thought experiments, here are seven of the most useful for making you reflect on everything around you.
Thought experiments are among the most important tools in the intellectual toolbox. Widely used in many disciplines, thought experiments allow for complex situations to be explored, questions to be raised, and complex ideas to be placed in an understandable context. Here we have seven thought experiments in philosophy you might not have heard of. With explanations of what they mean and what questions they raise.
The Veil of Ignorance
Justice is blind, should we be? (Mural of Lady Justice by Alex Proimos. (Wikimedia Commons))
This experiment was devised by John Rawls in 1971 to explore notions of justice in his book A Theory of Justice.
Suppose that you and a group of people had to decide on the principles that would establish a new society. However, none of you know anything about who you will be in that society. Elements such as your race, income level, sex, gender, religion, and personal preferences are all unknown to you. After you decide on those principles, you will then be turned out into the society you established.
Question: How would that society turn out? What does that mean for our society now?
Rawls argues that in this situation we can't know what our self-interest is so we cannot pursue it. Without that guidepost, he suggests that we would all try to create a fair society with equal rights and economic security for the poor both out of moral considerations and as a means to secure the best possible worst-case scenario for us when we step outside that veil. Others disagree, arguing that we would seek only to maximize our freedom or assure perfect equality
This raises questions for the current state of our society, as it suggests we allow self-interest to get in the way of progressing towards a just society. Rawls' ideas about the just society are fascinating and can be delved into here.
The Experience Machine
A scene from The Matrix, which revolves around simulated realities.
Robert Nozick came up with this one which appears in his book Anarchy, State, and Utopia.
Imagine that super neuroscientists have created a machine that can simulate pleasurable experiences for the rest of your life. The simulation is ultra-realistic and indistinguishable from reality. There are no adverse side effects, and specific pleasurable experiences can even be programmed into the simulation. Regarding pleasure experienced, the machine offers more than is possible in several lifetimes.
Question: Do we have any reason to not go in?
Nozick argues that if we have any reason to not get in then hedonistic utilitarianism, the idea that pleasure is the only good and that we ought to maximize it, is false. Many people value having real experiences or being a person who does things rather than dreams about doing them. No matter what the reason, if you don't go in you can't claim pleasure is the only good, and Nozick thinks most people won't go in.
There are counter-arguments, however. Some hedonists argue that people really would go into the machine or that we have a status quo bias that leads us to treat the reality we are currently in as more important than other, better ones. In either case, the experiment does present us with a problem for those who argue we only want pleasure.
An example of color, are you learning anything by seeing it you couldn't get out of a black and white book?
Philosopher Frank Jackson proposed this thought experiment in 1982; it raises questions about the nature of knowledge.
Mary lives in a black and white room, reads black and white books, and uses screens that only display images in black and white to learn everything that has ever been discovered about color vision in physics and biology. One day, her computer screen breaks and displays the color red. For the first time, she sees color.
Question: Does she learn anything new?
If she does, then it shows that qualia, individual occurrences of subjective elements of experience, exist; as she had access to all possible information other than experience before she saw the color but still learned something new.
This has implications for what knowledge and mental states are. Because if she learns something new then mental states, like seeing color, can't be described entirely by physical facts. There would have to be more to it, something subjective and dependent on experience.
If she doesn't learn anything new, then we would have to apply the idea that knowing physical facts is identical to experiencing something everywhere. For example, we would have to say that knowing all about echolocation is similar to knowing what it is like to use it.
This experiment is unique of the ones on this list as the author later changed their mind and argued that Mary seeing red doesn't count as evidence that qualia exist. However, the problems posed by the experiment remain widely debated.
A donkey who is much happier than the one in our experiment. (Wikimedia Commons)
Variations on this experiment date back to antiquity, this formulation was named after the philosopher Jean Buridan, whose views on determinism it ridicules.
Imagine a donkey placed precisely between two identical bales of hay. The donkey has no free will, and always acts in the most rational manner. However, as both bales are equidistant from the donkey and offer the same nourishment, neither choice is better than the other.
Question: How can it choose? Does it choose at all, or does it stand still until it starves?
If choices are made based on which action is the more rational one or on other environmental factors, the ass will starve to death trying to decide on which to eat- as both options are equally rational and indistinguishable from one another. If the ass does make a choice, then the facts of the matter couldn't be all that determined the outcome, so some element of random chance or free will may have been involved.
It poses a problem for deterministic theories as it does seem absurd to suppose that the ass would stand still forever. Determinists remain split on the problem that the ass poses. Spinoza famously dismissed it while others accept that the donkey would starve to death. Others argue that there is always some element of a choice that differentiates it from another one.
The life you can save
This experiment was written by famed utilitarian thinker Peter Singer in 2009.
Imagine that you are walking down the street and notice a child drowning in a lake. You can swim and are close enough to save her if you act immediately. However, doing so ruins your expensive shoes. Do you still have an obligation to save the child?
Singer says yes, you have a responsibility to save the life of a dying child and price is no object. If you agree with him, it leads to his question.
Question: If you are obligated to save the life of a child in need, is there a fundamental difference between saving a child in front of you and one on the other side of the world?
In The Life You Can Save, Singer argues that there is no moral difference between a child drowning in front of you and one starving in some far off land. The cost of the ruined shoes in the experiment is analogous to the cost of a donation, and if the value of the shoes is irrelevant than the price of charity is too. If you would save the nearby child, he reasons, you have to save the distant one too. He put his money where his mouth is, and started a program to help people donate to charities that do the most good.
There are counter-arguments of course. Most of them rely on the idea that a drowning child is in a different sort of situation than a child who is starving and that they require different solutions which impose different obligations.
The swamps of Louisiana, home to questions of identity? (Getty Images)
Written by Donald Davidson in 1987, this thought experiment raises questions about identity.
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.
Question: Is the Swampman the same person as the disintegrated fellow?
Davidson said no. He argues that while they are physically identical and nobody would ever notice the difference, they don't share a casual history and can't be the same. For example, while the Swampman would remember the friends of the disintegrated man, it never saw them before. Another person saw them and the Swampman just has his memories.
There are objections to the idea that the two characters in the story are different. Some argue that the identical minds of Swampman and the original person mean that they are the same person. Others, like philosopher Daniel Dennett, argue that the entire experiment is too far removed from reality to be meaningful.
This raises problems for teleportation as seen on Star Trek and for those who want to download their brains into a computer. Both cases rely on one version of you being created and one disappearing, but is the second version of you still you?
Famous violinist Isaac Stern. (Getty Images)
This one was written by Judith Thomson in her 1971 essay A Defense of Abortion. She writes:
“You wake up in the morning and find yourself back to back in bed with an unconscious violinist. A famous unconscious violinist. He has been found to have a fatal kidney ailment, and the Society of Music Lovers has canvassed all the available medical records and found that you alone have the right blood type to help. They have therefore kidnapped you, and last night the violinist's circulatory system was plugged into yours, so that your kidneys can be used to extract poisons from his blood as well as your own. If he is unplugged from you now, he will die; but in nine months he will have recovered from his ailment, and can safely be unplugged from you"
Question: Are you obligated to keep the musician alive, or do you cut him loose and let him die because you want to?
Thompson, who has several excellent thought experiments to her name, says no. Not because the violinist isn't a person with rights, but rather because he has no right to your body and the life-preserving functions that it provides. Thompson then expands her reasoning to argue that a fetus also lacks the rights to another person's body and can be evicted at any time.
Her argument is subtle, however. She doesn't say you have a right to kill him, only to stop him from using your body to stay alive. His resultant death is viewed as a separate, yet related, event that you have no obligation to prevent.
While legalization has benefits, a new study suggests it may have one big drawback.
- A new study finds that rates of marijuana use and addiction have gone up in states that have recently legalized the drug.
- The problem was most severe for those over age of 26, with cases of addiction rising by a third.
- The findings complicate the debate around legalization.
Cannabis Use Disorder, is that when you get so high you can’t figure out how to smoke anymore?
Cannabis use disorder, also known as CUD or cannabis/marijuana addiction, is a psychological disorder described in DSM 5 as "the continued use of cannabis despite clinically significant impairment." This includes people being unable to cut down on their usage despite wanting to, those who often use it despite finding it severely impairs their ability to function, or those who are putting themselves in danger to secure access to the drug.
While an understanding that marijuana can be addictive has existed for some time, and the image of the pothead who smokes so much they can hardly function is prevalent in our society, the effects of legalization on addiction rates have somehow gone understudied until now. Importantly, previous studies had failed to consider usage rates amongst populations over the age of 25.
In the new study, published in JAMA Psychiatry, focused on self-reported data on monthly drug use in four states where marijuana is now legal, Colorado, Washington, Alaska, and Oregon, from both before and after the drug was legalized in each state and compared it to others which have not yet legalized.
The data gave insights into the drug use habits of the respondents and specifically gave information about if they had smoked at all in the last month, the frequency of their drug use, and if they had ever had issues with how much they were using drugs.The researchers ultimately considered the responses of 505,796 individuals.
The increase in cannabis usage they found was considerable. The number of respondents over the age of 26 who claimed to have used the drug in the last month went up by 23% compared with their counterparts in states that have yet to legalize. Abuse of the drug by this group rose by 37%.
Teen usage rose by 25%, and addiction rates rose as well. This increase was small, though, and the authors have suggested it may be due to an unknown factor. The rate of usage or abuse for respondents between the ages of 18 and 25 did not increase at all.
After breaking the results down by demographics, the primary finding held; adults over the age of 26 are using marijuana more often when it is legalized, and they are starting to use it too much.
The grain of salt
As in any study where findings are self-reported, the exact numbers you see here should be taken with a grain of salt. They could be slightly higher or lower. As this study relies on people self-reporting their usage of a drug that is still illegal in many places, it is very possible that the apparent spike in addiction rates is caused by more accurate reporting, as people who live in an area where pot is still illegal may be less likely to report smoking it every day.
And it should be repeated a thousand times over that correlation and causation are not the same thing. There could be some unknown factor causing these increases in each case.
Despite these qualifications, the study is still useful in giving us a general sense of what may happen in states that have yet to legalize.
What does this mean for society and drug users?
While claims of "reefer madness" are greatly exaggerated, marijuana has several well established and thoroughly studied side effects. While occasional use isn't terribly harmful, addiction can be. Lead author Magdalena Cerdá of New York University explains in the study that heavy marijuana use is associated with "psychological and physical health concerns, lower educational attainment, decline in social class, unemployment, and motor vehicle crashes."
A substantial increase in the number of people who are addicted to the stuff will incur costs to society down the line.
Of course, a 37% increase in problematic usage means that the percentage of adults smoking too much went from .9% to 1.23% of the population responding to the survey. This makes it far less prevalent than issues with alcohol, which affected around 6% of all Americans in 2018.
Recently, Big Think's Philip Perry wrote a piece about how legalization could improve the health of millions by allowing the government to regulate the purity of commercially sold marijuana. This remains true. However, it must be weighed against the findings of this study, which suggests that at least some of these health gains will be wiped out by increased addiction rates.
What does this mean for legalization efforts?
The legalization steamroller will undoubtedly keep rolling along. While health concerns are one factor in the debate over marijuana, it is only one of many. In Illinois, where I live, weed will become legal on January 1st of 2020. The legalization campaign and legislation were more concerned with issues of social justice, the failures of prohibition, and finding a new source of tax revenue (since we're half broke) than with matters of potential addiction.
As Vox reports, the authors of the study aren't suggesting that legalization shouldn't take place; that is another, broader debate. They merely wish to present the fact that legalization has a particular side effect that we should be aware of.
While this study is unlikely to change anybody's stance on if weed should be legalized or not, it does show us a critical element to be considered when discussing drug policy. No drug is perfectly safe, and we have reason to believe that legalizing marijuana will mean that more people will have a hard time with it. Let's hope that legalization proponents keep that in mind as they rack up their victories.
For some reason, the bodies of deceased monks stay "fresh" for a long time.
It's definitely happening, and it's definitely weird. After the apparent death of some monks, their bodies remain in a meditating position without decaying for an extraordinary length of time, often as long as two or three weeks.
Tibetan Buddhists, who view death as a process rather than an event, might assert that the spirit has not yet finished with the physical body. For them, thukdam begins with a "clear light" meditation that allows the mind to gradually unspool, eventually dissipating into a state of universal consciousness no longer attached to the body. Only at that time is the body free to die.
Whether you believe this or not, it is a fascinating phenomenon: the fact remains that their bodies don't decompose like other bodies. (There have been a handful of other unexplained instances of delayed decomposition elsewhere in the world.)
The scientific inquiry into just what is going on with thukdam has attracted the attention and support of the Dalai Lama, the highest monk in Tibetan Buddhism. He has reportedly been looking for scientists to solve the riddle for about 20 years. He is a supporter of science, writing, "Buddhism and science are not conflicting perspectives on the world, but rather differing approaches to the same end: seeking the truth."
The most serious study of the phenomenon so far is being undertaken by The Thukdam Project of the University of Wisconsin-Madison's Center for Healthy Minds. Neuroscientist Richard Davidson is one of the founders of the center and has published hundreds of articles about mindfulness.
Davidson first encountered thukdam after his Tibetan monk friend Geshe Lhundub Sopa died, officially on August 28, 2014. Davidson last saw him five days later: "There was absolutely no change. It was really quite remarkable."
The science so far
Credit: GrafiStart / Adobe Stock
The Thukdam Project published its first annual report this winter. It discussed a recent study in which electroencephalograms failed to detect any brain activity in 13 monks who had practiced thukdam and had been dead for at least 26 hours. Davidson was senior author of the study.
While some might be inclined to say, well, that's that, Davidson sees the research as just a first step on a longer road. Philosopher Evan Thompson, who is not involved in The Thukdam Project, tells Tricycle, "If the thinking was that thukdam is something we can measure in the brain, this study suggests that's not the right place to look."
In any event, the question remains: why are these apparently deceased monks so slow to begin decomposition? While environmental factors can slow or speed up the process a bit, usually decomposition begins about four minutes after death and becomes quite obvious over the course of the next day or so.
As the Dalai Lama said:
"What science finds to be nonexistent we should all accept as nonexistent, but what science merely does not find is a completely different matter. An example is consciousness itself. Although sentient beings, including humans, have experienced consciousness for centuries, we still do not know what consciousness actually is: its complete nature and how it functions."
As thukdam researchers continue to seek a signal of post-mortem consciousness of some sort, it's fair to ask what — and where — consciousness is in the first place. It is a question with which Big Think readers are familiar. We write about new theories all the time: consciousness happens on a quantum level; consciousness is everywhere.
So far, though, says Tibetan medical doctor Tawni Tidwell, also a Thukdam Project member, searches beyond the brain for signs of consciousness have gone nowhere. She is encouraged, however, that a number of Tibetan monks have come to the U.S. for medical knowledge that they can take home. When they arrive back in Tibet, she says, "It's not the Westerners who are doing the measuring and poking and prodding. It's the monastics who trained at Emory."
When Olympic athletes perform dazzling feats of athletic prowess, they are using the same principles of physics that gave birth to stars and planets.
- Much of the beauty of gymnastics comes from the physics principle called the conservation of angular momentum.
- Conservation of angular momentum tells us that when a spinning object changes how its matter is distributed, it changes its rate of spin.
- Conservation of angular momentum links the formation of planets in star-forming clouds to the beauty of a gymnast's spinning dismount from the uneven bars.
It is that time again when we watch in awe as Olympic athletes perform dazzling feats of athletic prowess. But as we stare in rapt attention at the speed, grace, and strength they exhibit, it is also a good time to pay attention to how they embody, literally, fundamental principles that shape the entire universe. Yes, I'm talking about physics. On our screens, these athletes are giving us lessons in the principles that giants like Isaac Newton struggled mightily to articulate.
Naturally, there are many Olympic events from which we could learn some basic principles of physics. Swimming shows us hydrodynamic drag. Boxing teaches us about force and impulse. (Ouch!) But today, we will focus on gymnastics and the cosmic importance of the conservation of angular momentum.
The conservation of angular momentum
Much of the beauty of gymnastics comes from the spins and flips athletes perform as they launch themselves into the air from the vault or uneven bars. These are all examples of rotations — and so much of the structure and history of the universe, from planets to galaxies, comes down to the physics of rotating objects. And so much of the physics of rotating objects comes down to the conservation of angular momentum.
Let's start with the conservation of regular or "linear" momentum. Momentum is the product of mass and velocity. Way back in the age of Galileo and Newton, physicists came to understand that in the interactions between bodies, the sum of their momentums had to be conserved (which really means "does not change"). This is a familiar idea to anyone who has played billiards: when a moving pool ball strikes a stationary one, the first ball stops while the second scoots away. The total momentum of the system (the mass times velocity of both balls taken together) is conserved, leaving the originally moving ball unmoving and the originally stationary ball carrying all the system's momentum.
Credit: Sergey Nivens and Victoria VIAR PRO via Adobe Stock
Rotating objects also obey a conservation law, but now it is not just the mass of an object that matters. The distribution of mass — that is, where the mass is located relative to the center of the rotation — is also a factor. Conservation of angular momentum tells us that if a spinning object is not subject to any forces, then any changes in how its matter is distributed must lead to a change in its rate of spin. Comparing the conservation of angular momentum to the conservation of linear momentum, the "distribution of mass" is analogous to mass, and the "rate of spin" is analogous to velocity.
There are many places in cosmic physics where this conservation of angular momentum is key. My favorite example is the formation of stars. Every star begins its life as a giant cloud of slowly spinning interstellar gas. The clouds are usually supported against their own gravitational weight by gas pressure, but sometimes a small nudge from, say, a passing supernova blast wave will force the cloud to begin gravitational collapse. As the cloud begins to shrink, the conservation of angular momentum forces the spin rate of material in the cloud to speed up. As material is falling inward, it also rotates around the cloud's center at ever higher rates. Eventually, some of that gas is going so fast that a balance between the gravity of the newly forming star and what is called centrifugal force is achieved. That stuff then stops moving inward and goes into orbit around the young star, forming a disk, some material of which eventually becomes planets. So, the conservation of angular momentum is, literally, why we have planets in the universe!
Gymnastics, a cosmic sport
How does this appear in gymnastics? When athletes hurl themselves into the air to perform a flip, the only force acting on them is gravity. But since gravity only affects their "center of mass," it cannot apply forces in a way that changes the athlete's spin. But the gymnasts can do that for themselves by using the conservation of angular momentum.
By changing how their mass is arranged, gymnasts can change how fast they spin. You can see this in the dismount phase of the uneven bar competitions. When a gymnast comes off the bars and performs a flip by tucking their legs inward, they can quickly increase their rotation rate in midair. The sudden dramatic increase in the speed of their flip is what makes us gasp in astonishment. It is both scary and a beautiful testament to the athletes' ability to intuitively control the physics of their bodies. And it is also the exact same physics that controls the birth of planets.
"As above so below," goes the old saying. You should keep that in mind as you watch the glory that is the Olympics. That is because it is not just athletes that have this intuitive understanding of physics. We all have it, and we use it every day, from walking down the stairs to swinging a hammer. So, it is no exaggeration to claim that the first place we came to understand the deepest principles of physics was not in contemplating the heavens but moving through the world in our own earthbound flesh.