Can a chosen definition be “wrong”? No. If you choose a definition, then you can define a sound or series of characters to mean whatever you want them to mean. For instance, if you wanted, you could declare that whenever you say “phloop,” you mean one of those little paper umbrellas that are sometimes found in Piña coladas. That would be weird, but it wouldn’t be “wrong.” But we suggest that there are at least seven ways a definition can be “lousy.” 

By understanding what makes a good definition and what makes a lousy one, you can better formulate your ideas, and you can better spot mistakes in other people’s arguments. For instance, you might be in a situation where you’re trying to define the essence of an idea you came up with or characterize the unique career role that you’ve designed for yourself. Alternatively, you might be struggling to understand a definition that someone else is using, and you want to diagnose why exactly you’re finding it confusing. The words we use are crucial to the success of the interactions we have, and it is very handy to be able to pinpoint when a particular word is making a conversation more confusing than it needs to be. So, here are the things that we think make for lousy definitions! 

1. Miscommunication

If you decide the word “dog” refers to cats, people are going to be very confused.

Similarly, if you’re talking to someone who uses the word “racism” to mean X (say, “an explicitly held and endorsed belief that some racial groups are inferior to others”), and you use it to mean Y (say, “any form of negative generalization or attitude to a racial group, whether it’s implicit or explicit”), your conversation is probably not going to go as well as you would like until you identify that difference in usage. For these reasons, good definitions shouldn’t reuse terms that people are already familiar with or have multiple meanings associated with them. A good way to avoid the latter is to clarify upfront what you mean when you’re using a particular definition if the other person might not know what you mean when using that word.

2. Irrelevance

If you define a “dooooog” to be a dog with more than five legs, you’re not going to find it to be useful for much of anything. Dogs like that probably do exist, but they are not something almost anyone ever needs to refer to. We want our definitions to aim toward the things we are likely to want to reference.

For instance, someone bothered to define the word “Rasceta” to mean the crease commonly found going across a person’s wrist. Presumably, there is some subculture where that is a useful word, but very few people will ever need to know that definition. 

3. Unnaturalness

If you define “dogephant” to include all dogs smaller than 10 pounds AND all elephants more than 8000 pounds, you have not “carved reality at the joints.” Because of mixing things that aren’t clearly alike, using this definition makes communicating more muddled than it needs to be.

Another instance of this phenomenon is our use of the word “selfish.” Sometimes people define the word “selfish” in such a way that it includes both “stealing money from someone” and “sacrificing your own life to save the life of ten others because you feel such a strong emotion of compassion for those people;” it’s about doing things that make you feel “good.” An alternate reading of “selfish” might be much more negative: it’s about taking actions which benefit you at the cost of other peoples’ wellbeing.

4. Opinionatedness

If you define “dogmor” to be “those dog-loving morons who somehow are convinced that dogs are better than cats,” then the definition imports both a debatable opinion and an emotional slant into its meaning, causing usage of this word to be infected with either or both of these things.

For example, the word “sissy” not only suggests that someone — usually a boy or man — embodies feminine qualities but carries with it a negative, insulting connotation. If your aim is to make certain people feel bad, then this might be a good strategy to take, though you might be being a jerk, and that approach doesn’t make for clear, unbiased communication.

5. Ambiguity

If by “dogdog” you mean anything that a dog can like, then your word is (1) hard to use and (2) hard to think about; dogs like a large range of things, and individual dogs also have distinct preferences!

The word “problematic” (when used without clarification) is another (problematic) example of a definition: the problem being referred to could be of many different types and could range from quite objective to just the idiosyncratic, subjective opinion of the writer.

6. Inefficiency 

If you define “doglegs” to be anything with the legs of a dog, and “dogface” to be anything with the face of a dog, etc., then you can talk about walking your dog by saying, “I just got back from walking a creature with doglegs, dogface, dogfur, dogheart, …” But this is a ridiculously inefficient way to talk about your dog! Some definitions make communication substantially more efficient since they compress lots of information you commonly want to express into a small package.

Consider a different instance of this: it is possible to talk about calculus without having a word that means “the derivative” (e.g., by always referring to “limits of functions”), but this is going to be a painful and inefficient way to think and communicate. The word derivative makes ideas in calculus much easier to talk about. 

7. Lack of precision

If you define “floofster” to be any animal with fur, then you will not be communicating very precisely when you say, “I pet my floofster this morning.” You may be saying something true (and rather adorable), but someone will not know if you were petting a dog, a cat, or something more exotic like a lizard wearing a fur coat! Ideally, we want our definitions to focus on just those items or concepts we are trying to communicate.

Similarly, if you say to your friend, “I’m feeling bad,” the ambiguity of the word “bad” makes it harder for them to understand what you’re going through. If you say, “I have a headache,” then it will be easier for your friend to help you. Even better, if true, would be to say, “I have a migraine.” 

So, no chosen definition can be “wrong,” but plenty of definitions are “lousy.” To prevent lousy definitions, you should choose definitions that:

(1) allow clear communication, 

(2) refer specifically to the things of interest, 

(3) carve reality at the joints, 

(4) don’t sneak in debatable opinions/slants, 

(5) are relatively unambiguous, 

(6) express more information in fewer words, and 

(7) allow us to be more exact and specific with our words. 

We hope you found this helpful!

This piece first appeared on the Clearer Thinking blog on March 2, 2021, and was published on this site on December 16, 2022.

What causes journalistic distortion?

1. Equal time to each side. There are many issues for which there are two or more reasonable positions that a person can hold. Then there are those issues where one side is supported by nearly everyone who has relevant expertise, and only a few fringe people oppose that view. The trouble is that stories about highly unbalanced issues can lead to a false impression of balance, either because the journalist feels compelled to spend equal time discussing each view-point, or because the journalist is himself unaware of which side is more trustworthy. And a person with highly unrepresentative but highly quotable opinions may be quoted in the article more than is warranted. It may seem less biased to present both sides, but when one side is almost certainly right, an equal presentation may distort more than it informs.

2. Selective reporting. Since news organizations are in the business of selling the news (or, at least, driving traffic to their websites) they have a monetary incentive to produce news that people will be eager to read. Feel-good stories about a dog saving someone’s life can beat out information that might be more important or relevant to most people. What’s problematic from a reality distortion perspective though is that the rate at which events occur and the rate at which they are reported are massively out of sync. For each story about someone coming home from work only to be murdered by their ex-boyfriend, we never hear the millions of tales of people coming home to work only to sit down and eat dinner. This is problematic because the way the human brain tries to estimate how likely something is to occur involves an attempt to retrieve instances of that thing in memory. The more easily you can retrieve those instances, the more frequent you will tend to assume that thing is. If you’ve recently read about a few murder cases, you may have the impression that murder has become more common than it used to be, even if this is merely an artifact of journalists choosing (for whatever reason) to report on more murders. If you can easily think of an example of a shark attack, you may overestimate the frequency of sharks killing people.

The vividness of the accounts we hear can also alter our perception. A vivid retelling not only increases the chance that we remember an account, but also tends to increase our emotional response to it. If you’ve recently read an article that described a gruesome murder in horrid detail, you may subsequently be more afraid when walking alone on an empty street. Through this mechanism, news reading can cause people to have excessive fear of things that aren’t very likely to harm them, and fail to fear far more dangerous things that are rarely reported on. You’re much more likely to die in a car crash than be killed by terrorism, yet in a world where terrorism is reported on constantly, you will likely fear terrorism more.

3. Mix-ups of correlation and causation. Just because X tends to occur together with Y doesn’t mean that X causes Y. In fact, it could be that Y causes X instead, or that both X and Y are caused by some third thing. Unfortunately, reporters frequently get this wrong (or at least fail to make the distinction clear to the reader), especially when reporting on scientific findings. Articles will insinuate that since the latest study found higher wine/broccoli/nicotine consumption was associated with greater longevity/health/focus, that means that wine/broccoli/nicotine must actually cause those benefits. A related problem that you’ll sometimes see (especially in articles about finance) is the implication that since Y came after X, that means that Y was caused by X. It may be true that many stock market investors reacted negatively to a new bill that was just signed into law, but that doesn’t mean that’s a causal explanation of why the stock market fell 1% today. There surely were many factors influencing the change in the market’s price, some tending to push it up, others tending to push it down. Even if it were true that the signing of the bill had a strong effect (which it might be difficult to confirm), that event certainly cannot take all the credit for determining the change in the market’s price.

4. Use of low quality studies. Just because a study “proves” something, doesn’t make it so. In fact, most studies that are conducted are of poor quality for one reason or another. This could be due to a small number of study participants, lack of a control group, lack of randomization, the wrong choice of statistical test, flawed experimental protocol, poor choice of outcome measures, selective reporting of study results, or a variety of other reasons. Unfortunately, journalists rarely make it clear whether a study was of high quality, being mainly interested in what the study claimed to have found. Even the reporting of high quality studies can be problematic, if the journalist fails to mention other high quality studies that found different results. Given all the things that can go wrong in the design and execution of a study, we should be hesitant to accept the results even of those studies that look to be of high quality, until we have seen replication of the study by a different research team.

5. Lack of understanding. Many journalists write about a wide range of subjects. It is rare that they are true experts in the subject of a particular article. But as non-experts writing about what are sometimes very complicated subjects, there is the danger that journalists misunderstand the underlying subject matter. This problem occurs especially often in articles about highly technical research. The issue is compounded further by the fact that journalists are often working under tight deadlines, and so may lack the ability to do extensive background research.

6. Selective use of the facts. Even within a single story, the problem of selective reporting can be substantial. Not all facts in a case are equally entertaining or fit the narrative equally well. There is some incentive to favor those facts that improve the story over drier, though perhaps important material. Of course a political or other agenda on the part of the reporter can also determine which facts he chooses to report on. Since there is a tendency for liberals to read liberal news sources while conservatives read conservative sources, both groups may have their pre-existing views bolstered by selectively reported evidence.

7. Exaggeration of importance. News sells better if it sounds important, so news organizations have an incentive to make their news fit this criteria. One way to do this is to report on stories that actually matter to a lot of people, but sometimes it is better for the organization to just make whatever they’re reporting on sound more important than it is. The next big scientific breakthrough reported on turns out to be completely forgotten a few years or months later (but who remembers?) One of the most common forms of exaggeration in journalism is when a trend is constructed from a few data points. If a handful of celebrities are eating a lot of coconut, or museums have recently become a little more popular among people in their twenties, that doesn’t mean there’s a new fad that the world should hear about.

Choose your news sources carefully, because the information you consume determines what you believe about the world. And as incredibly valuable as journalism is, it can distort reality.

Disagreements can be caused by:

1. Facts. People have access to different information. One person has studied physics, another hasn’t. One has spent years reading American news sources, another, Chinese ones. Differing sources will expose people to different facts about the world, which can naturally lead to disagreement. People have had different personal experiences as well, which can lead them to have different world views.

2. Definitions. Words are used differently by different people. One says “God” to mean the god of the old testament, another uses it to mean a guiding force in the universe. One says “art” to mean what is considered valuable by the art establishment, another to refer to creative works that evoke emotion. Typically, people do not even know precisely what they themselves mean when they use words. This isn’t a problem most of the time, but can cause confusion in certain cases. Suppose I take a chair and table, cut them both in half, glue one half of the table to one half of the chair with the cut edges touching, and paint the whole thing gold. Is the object I’ve constructed a table, a chair, both or neither? Our usual usage of the words “chair” and “table” are not well specified in this case, so we have trouble answering the question. I don’t know precisely what you mean by “chair”, and I don’t even know precisely what I mean by it. When I hear the word it triggers associations, memories, an image, but not a precise definition. When people are using different definitions they frequently get into unproductive arguments about those definitions without realizing that they are merely using words differently. “That’s not art, it’s just an old urinal that someone found and put in a gallery.” “Of course it’s art, it’s hanging in a museum, and clearly evokes emotion in the viewer!”

3. Values. People value and care about different things. One person thinks that more life in the universe is inherently a good thing, and so is in favor of increasing the size of the population. Another would prefer less life to be created if that would keep the existing people happier. One man places value on being remembered after he is dead, while another person doesn’t value it because she knows she won’t be able to experience that state of the world. Utilitarians place value on the world containing less suffering, Kantians value a world where certain universal rules are not violated, many people place value on the survival of animals species (even in cases where their survival does not benefit human beings), and so forth. There is nothing strange about different minds producing different labels for what is valuable and what lacks value. It does occasionally happen though that a person’s values are logically inconsistent (for instance, the person claims to value X while disvaluing Y, without realizing that X and Y amount to the same thing). [Comment: Related to values are the issues of tastes, preferences and interests. If you have a taste for chocolate rather than mushrooms, then you have an interest in going to the chocolate store rather than the mushroom store. A disagreement might then ensue regarding which store you “should” go to between you and someone with the opposite preferences. When you say “should” here it may be merely expressing your preference, but the conversation can take the form of a disagreement over what to do.]

4. Signaling. Sometimes people disagree (or claim to disagree) merely to signal information to others. For instance, they might say they disagree with someone they don’t like to demonstrate their dislike, or they might agree with someone they like to make that person like them more. They might say that Shakespeare wrote fantastic plays not because they enjoy reading those plays, but because they want to be respected for being a literary intellectual. They might say that they love the Yankees because that makes them more accepted by their group of friends.

5. Failures of logic. If the people on one or both sides of argument are engaging in logical fallacies or other failures of reasoning, they may end up disagreeing as a result. One person may argue that individual humans will never be able to live for more than 200 years because it has never happened before, while another will claim that we will definitely one day have lifespans longer than 200 years having extrapolated from the increase in longevity over the past 10,000 years. Since both sides have fallacious reasoning in this case, there is no reason to expect them to agree (unless their false logic just happens to lead them in the same direction). We can also include in this category the case where one person doesn’t have sufficient reasoning ability to understand an argument, and so is unable to properly evaluate it. Then, that person may disagree with the conclusion of the argument as a consequence of the argument being inaccessible to them.

6. Competition. Sometimes disagreement is simply about scoring points for our side, at the expense of the other side. In political disagreement, the underlying goal may be to have your own group look good (e.g. to increase support for your group) or to have the other group look bad (e.g. to weaken their power or even humiliate them). For groups within organizations, disagreement may really be about a power struggle: which group should be able to make decisions about which things, and what magnitude of resources should be allocated to each group? We also may just dislike an individual person, and so deny facts that would make them look good, or claim something that makes them look bad. When we are having a disagreement with a person from another group about a standard topic on which our group and their group tend to fight, we should apply some skepticism and wonder whether the disagreement really has to do with the truth at all, or if it’s more accurate to think of it as a battle over group status, esteem or resources.

7. Information processing methods. If people use different methods for processing information, they may end up disagreeing, even if the methods that each person relies on is quite reasonable. Brains do not perfectly update the strength of beliefs when encountering new information. Given limited computational resources, and the constraint that our brains evolved via natural selection, approximations like imperfect updating of credence are to be expected. If two brains both have pretty good but imperfect methods of updating beliefs based on evidence, they may end up disagreeing, even though they are both about as reliable as one another. When we reason explicitly information processing disagreements can also arise. For instance, if we want to estimate the chance that a friend will cancel on us for dinner, it is not obvious how we should weight our knowledge about how often friends cancel on us in general, compared to our knowledge about how often this particular friend has canceled on us. We have more data on all of our friends, which makes that estimate more reliable, but the data on this particular friend is more relevant to the particular case. Ideally, all of the known information should be combined in some way, but one can reasonably disagree about the best way to do this.

8. Default beliefs. If you were to design an intelligent being, it would start off with certain beliefs (implicitly, if not explicitly) and it would be silly, if not impossible, to have it start by assigning a precisely equal probability to every possible state of the world. If the prior/default knowledge of two intelligent beings differs, they may come to different conclusions, even when they processed information in precisely the same way and have access to all the same information. If a human baby, an alien baby, and a robot were raised in precisely the same environment, they might end up believing substantively different things about the world merely because their brains have different built in assumptions. Their brains might, for instance, start out assuming different things about the nature of other intelligent beings.

9. Self-interest. On a basic level, Bob probably cares about Bob’s well being more than he cares about Karen’s, and Karen probably cares about Karen’s well being more than she cares about Bob’s. While Bob and Karen may explain a disagreement in other, less self interested terms (e.g. “I think it’s best for the company if we move offices”), it could simply be that they are each acting self interestedly and have different interests. More subtly though, it often happens that people’s brains will make it hard for them to see the truth, because the truth will have negative consequences for them. Take, for instance, the case of someone raised their entire life in an extreme cult. If they encounter evidence that the cult’s beliefs are false, they are likely to experience intense anxiety, because finding out and believing that the cult is wrong could have very severe negative consequences for them, such as causing them to be cut off from all of the people they love. Hence, there may be intense psychological pressure not to think about this evidence anymore, or to come up with a rationalization for why the evidence must be wrong, which will be immediately rewarding by eliminating the anxiety. Effectively, your brain may not let you see the truth because it anticipates the negative consequences from doing so, and it is trying to protect you from those consequences.

Suppose that two intelligences (people, aliens, A.I.s, etc.) exchange information about their beliefs, and their reasons for having those beliefs. If they start with the same default beliefs, employ the same information processing methods, do not make errors when they explicitly reason, are able to follow each other’s reasoning, share the same values, use the same definitions, and have access to the same facts (for instance due to exchanging factual information with each other), then you should expect those two intelligence to reach agreement.

Note, however, that these nine categories of disagreement are not entirely independent from each other. For instance, the distinction between bad information processing methods and illogical argumentation can blur. A poor choice of definitions can also be a form of illogical thinking when those definitions are meaningless (“Let’s define a squircle to be a square circle”). And the distinction between default beliefs and built in information processing methods can be fuzzy as well, since the effectiveness of information processing methods may depend on assumptions those methods make about the environment. It is also a possibility that there are disagreements which arise that aren’t due to any of the nine reasons listed above (should any other types of disagreements occur to you, please post them in the comments below!).

Let’s see how this categorization system can help us understand real world debates. As our example we’ll use the debate about when abortion should be legal (a convenient choice because this debate has many facets and great complexity), taking into account the arguments frequently used by liberals and conservatives in the United States. A 2006 survey found that 60% of self-described “liberal democrats” thought that “abortion should be generally available”, versus 17% of self-described “conservative republicans”. Furthermore, 68% of these conservative republicans thought it should be either “illegal with few exceptions” or “never permitted” versus 23% of the liberal democrats. We’ll stick to considering this debate in terms of the first six reasons listed above that cause people disagree, since these six are often very useful frames of analysis.

1. Facts. Liberals and conservatives tend to be exposed to different information. For instance, it would not be surprising if liberals were more likely to hear about ways in which women are negatively impacted by not having access to abortions, while Conservatives were more likely to hear about women who regret having had abortions. Most of us tend to spend time with people that share many of our beliefs, and to read news from sources that are at least somewhat aligned with those beliefs. That means that the facts and ideas we hear tend to support what we already think is true. We should expect the friends and news sources of liberals to propagate more information supporting liberal values, and likewise for the friends and news sources of conservatives. Even google reinforces this tendency, when we happen to structure our queries in such a way that the results confirm our beliefs, and when Google automatically customizes our search results to be drawn from sources that are similar to those that we visit frequently.

The obvious solution to disagreements over facts is to exchange information with those you disagree with. This works well when people on the other side of the debate trust your sources as much as you do, and when they are willing to allow facts to change their minds. In practice, both of these assumptions are frequently violated. People commonly disregard information that contradicts their own beliefs, and latch onto the information that supports what they already think. When you encounter someone doing this, you can try asking the other person “what information WOULD make you change your mind about this issue, if that information were actually true?” That at least has a chance of getting the person to pre-commit to changing his or her mind if the relevant information can be found.

2. Definitions. The abortion debate is frequently phrased in terms of whether a fetus can be said to be a “person” (or, similarly, a “human being”), with the argument going “It is wrong to kill a person, so if a fetus is a person, killing it is wrong.” This would seem to imply that if we can just decide whether a fetus is a person then the question will be answered. But this begs the question of what we mean by “person.” We all agree with that Barack Obama is a person, but the usual definition we use for person isn’t clear cut enough to decide whether that word applies to the fetus case. And even if it were clear cut, it wouldn’t matter. The underlying question is not whether a fetus is a person, but whether we place disvalue on the death of fetuses, and if so, how much, and why. Phrasing the question in terms of whether a fetus has the status of person is bound to lead to disagreement, since intuitions about what “person” means differ quite substantially, and when one person says “a fetus is a person” and another says “a fetus is not a person” they may well not being using the word person to mean the same thing.

A handy trick for helping to resolve disputes over definitions is to taboo your words. Basically, this means replacing any confusing or fuzzy words with other words that get more closely at what you are trying to say. So, rather than “person” say “being that can suffer”, or “creature that cares about whether it lives or dies”, or “thing that is or one day will be an adult human”, or whatever else it is that you are really trying to denote with that word. In other words, if you’re stuck debating whether something is or is not a person, ban the word “person” from the conversation and use a more descriptive phrase. Now see if that allows the conversation to move forward.

3. Values. Some people place negative value on suffering, and believe that aborting a fetus is wrong if it causes the fetus to suffer, and that it is not wrong if there is no suffering. Others place negative value on the death of conscious entities, and so oppose abortion at the point that a fetus can reasonably be said to be conscious. Still others oppose depriving a being of its potential for future experiences, and so are anti-abortion on these grounds. Some people value rights, and believe the mother’s right to look out for her own interests trump those of the fetus until the point when the baby is self aware enough to get rights of its own. Still others value the life of anything that will become a human being, which includes fetuses.

Even though people can value different things without either of them being wrong, it still is sometimes possible to change what people are willing to say they value. For instance, you can try to demonstrate to them that one of their values conflicts with another of their values, which can cause one of those values to shift. Or you can try to show them that they do in fact value something that they claim not to, and prove it by means of an extreme example designed to provoke emotion.

4. Signaling. Abortion debates sometimes devolve into claims that those in favor of abortions are “against life” or that those opposed are necessarily “against women”. Obviously those who are pro abortion almost never actually want fetuses to die, they just want the mother to have a choice of whether to give birth. Likewise, there are of course reasons one may oppose abortion due to concerns about the loss of life of the fetus while simultaneously supporting rights for women more generally. When we use phrases like “against life” or “against women” they typically serve to demonstrate our group identity, and label the other side as bad guys. They say a lot about our emotional reactions and how we want our side and the other side to be viewed, but little about what the other side actually believes.

5. Failures of logic. Bad arguments are a prominent part of the abortion debates. Some such arguments fail because they rely on the ambiguity of words and assumptions that are left unexplained. For instance: “fetuses are human life, and human life is sacred, so killing fetuses is wrong.” Some take logical leaps that are not sufficiently filled in: “since an early term fetus can’t survive without the mother’s body, it is the mother’s choice whether to kill it”. Other arguments are true, but don’t demonstrate the claim they are used to support: “abortion is dangerous to mothers because it caries health risks”. Of course, this leaves out the fact that child birth itself carries substantial risks to the mother. Other arguments lead to question begging: “A women has a right to control what happens to her body, so she is justified in having abortions.” Where does this right come from, and if there is such a right, why does it trump other rights that might come into play in this case?

Convincing other people that their arguments are illogical, and identifying failed logic in our own arguments can be quite hard. A helpful tactic for dealing with illogic in others is to ask them to clarify their argument, rather than outright attacking it. For instance, saying “could you explain why X implies Y, as I’m having trouble seeing the connection” rather than saying “X doesn’t imply Y, you idiot.” Generally, the more people feel attacked, the more they feel they need to defend themselves, and the more likely it is that discussions with them will devolve into fights. Another useful technique, if you’re having trouble making headway, is to rephrase your disagreement with them. If they claim “X or Y” must be true, rather than just saying “that isn’t right” for the third time, you can try “Can you think of any other possibilities besides X and Y? Because I’m not convinced that one of them has to be true.” Or if someone says “X implies Y” and you’re quite sure it doesn’t, you can ask “so if Y were not true, you think that would imply that X is not true?” This helps people look at their own claims from a different angle, which may make them realize problems in their arguments that they didn’t identify before.

6. Group Competition. At first glance the argument may be about abortion legalization, but is it really about abortion legalization? Or is it more about trying to show that the other group is bad, for instance by trying to demonstrate they have no respect for women’s rights, or that they have no respect for the rights of the unborn? It may be that this is better understood as a fight about whose group is good or bad, or an attempt to increase group membership (if the disagreement is carried out in the public sphere), rather than a debate over what’s true.

When we encounter a complex and difficult to resolve disagreement, we can gain insight into why it is occurring and how it might be resolved by considering the roles of the nine (and particularly, the first six) fundamental reasons for disagreement: (1) facts, (2) definitions, (3) values, (4) signaling, (5) failures of logic, (6) group competition, (7) information processing methods, (8) default beliefs, and (9) self-interest.

Sometimes it is argued that using obscure words is good because they allow us to more concisely express precise connotations than we otherwise could. Instead of saying “There were many hats in the barn” we can say “There was a plethora of hats in the barn.” The latter phrase means more than that there were just a lot of hats.

The issue though, is that most people don’t know the precise connotations of obscure words, and the word “plethora” serves as a good example. It is often defined to mean not just “a lot”, but an excess or overabundance. However, when you see the word used in context, while the implication of “many” is often clear, the specific connotations can be much less so. If you’ve never looked it up, but have just tried to understand the word from seeing its usage, it can be quite hard to pickup on this nuance. And if you do take the time to look it up, it can be easier to retain the gist than its subtleties, so one may forget the part about “excess” and remember only “a lot”. Since, by definition, obscure words don’t occur very often, we likely have not seen them used a great many times. That means that compared to common words, we don’t have many data points from which to infer precise meanings. Even if according to the dictionary “plethora” carries just the message you hope to express, that matters little if the people you are communicating with don’t understand your precise meaning.

Even those who know that the word “plethora” often has a connotation of excess may be doing little more than translating “plethora” to “excess” in their minds. That is, they might not have seen the word used enough times for “a plethora of pineapples” to mean something beyond “an excess of pineapples”. When this is true, little is gained by using “plethora” instead of just “excess.” The former is certainly less likely to be understood than the latter. And though it is true that the former sounds more sophisticated to some people and can act as a signal of education level, this can backfire at times. Some audiences will view the use of this word as pretentious, and according to one study at least, “Consequences of erudite vernacular utilized irrespective of necessity”, writing using complex vocabulary may even cause you to be viewed as less intelligent in certain contexts.

If you are writing poetry or fiction, where the beauty of the language can be as important as the content, a varied vocabulary is probably quite useful. But if your overriding goal in speech or writing is to communicate information, avoiding obscure words is usually a good idea. Of course, what counts as obscure will vary depending on the audience (if you’re speaking to mathematicians, words that are common in math papers but are obscure in typical english will, of course, be fine). But, generally speaking, words that are uncommonly used are less likely to be understand than common words, and even in cases when they have precise connotations that it would be useful to convey, those connotations may not be fully understood by your audience.

These considerations can lead us to an odd conclusion. If your goals prioritize communicating information over expressing yourself elegantly, you may actually be better off knowing fewer words. The trouble is that if you know obscure words well, you will be less likely to realize how obscure they are, and may use them automatically without even considering that others may misunderstand them. Having a large vocabulary is viewed, nearly universally, as a good thing, but in fact there can be negative consequences to making your vocabulary too large.

Before using an obscure word, ask yourself, “Is this really the clearest way to communicate what I’m trying to say?”

• Making Observations
• Formulating Theories
• Making Predictions
• Testing Predictions
• Developing Happiness

Making Observations could include exercises where students make and record observations about the physical world, biological world, social world, political world, cultural world, etc. The tools students would learn about and employ could include stop watches and rocks to study how gravity works, telescopes to study the stars, microscopes to analyze blood, newspapers to study the government, and televisions to examine culture. Students would learn to operate these tools, pay attention, record, summarize, categorize, explain and simplify.

In Formulating Theories, students could learn about equations, probability, data, evidence, induction and deduction. They could study how various physical, psychological, economic, literary, musical and artistic theories arose. And they could be asked to develop their own theories about art, literature, culture, physical phenomena, psychological facts, and so on.

The subject Making Predictions would involve the study of many of the powerful theories from physics, economics, chemistry, and psychology, and students would learn to use each of these theories to make predictions about what one should expect to see.

In the study of Testing Predictions, students could learn about the scientific method, falsification, statistics, markets, computer prediction algorithms, the prediction algorithms of the brain, and randomized controlled trials. They could also learn how to do thorough research in order to be able confirm or disconfirm their future predictions based on knowledge gathered by others.

For Cultivating Happiness, there would be an emphasis on art appreciation, literature appreciation, food criticism, movie criticism, creative writing, art creation, meditation, exercise, health, positive psychology, cognitive therapy, etc. all directed towards learning how to increase pleasure, enjoyment and fulfillment as well as reduce misery. This could also involve a study of what makes humans happy and what makes them unhappy, which could lead to discussions of governmental systems, psychology, sociology, ethics, history, etc.

New ways of carving up knowledge can give us new ways of thinking about education.