Status paradox

A status paradox is a proposition that a subject is a member of two mutually exclusive classes.

Syllogistic

Syllogistic fallacies are kinds of invalid categorical syllogisms. This list contains the fallacy of undistributed middle and the fallacy of four terms, and a few others though there are a great many such formal fallacies.

Sweeping Generalization

See Fallacy of Accident.

Suppressed Evidence

Intentionally failing to use information suspected of being relevant and significant is committing the fallacy of suppressed evidence. This fallacy usually occurs when the information counts against one's own conclusion. Perhaps the arguer is not mentioning that experts have recently objected to one of his premises. The fallacy is a kind of fallacy of Selective Attention.

Example:

Buying the Cray Mac 11 computer for our company was the right thing to do. It meets our company's needs; it runs the programs we want it to run; it will be delivered quickly; and it costs much less than what we had budgeted.

This appears to be a good argument, but you'd change your assessment of the argument if you learned the speaker has intentionally suppressed the relevant evidence that the company's Cray Mac 11 was purchased from his brother-in-law at a 30 percent higher price than it could have been purchased elsewhere, and if you learned that a recent unbiased analysis of ten comparable computers placed the Cray Mac 11 near the bottom of the list. If the relevant information is not intentionally suppressed by rather inadvertently overlooked, the fallacy of suppressed evidence also is said to occur, although the fallacy's name is misleading in this case. The fallacy is also called the Fallacy of Incomplete Evidence and Cherry-Picking the Evidence. See also Slanting.

Superstitious Thinking

Reasoning deserves to be called superstitious if it is based on reasons that are well known to be unacceptable, usually due to unreasonable fear of the unknown, trust in magic, or an obviously false idea of what can cause what. A belief produced by superstitious reasoning is called a superstition. The fallacy is an instance of the False Cause Fallacy.

Example:

I never walk under ladders; it's bad luck.

It may be a good idea not to walk under ladders, but a proper reason to believe this is that workers on ladders occasionally drop things, and that ladders might have dripping wet paint that could damage your clothes. An improper reason for not walking under ladders is that it is bad luck to do so.

Subjectivist

The subjectivist fallacy occurs when it is mistakenly supposed that a good reason to reject a claim is that truth on the matter is relative to the person or group.

Example:

Justine has just given Jake her reasons for believing that the Devil is an imaginary evil person. Jake, not wanting to accept her conclusion, responds with, "That's perhaps true for you, but it's not true for me."

Style Over Substance

Unfortunately the style with which an argument is presented is sometimes taken as adding to the substance or strength of the argument.

Example:

You've just been told by the salesperson that the new Maytag is an excellent washing machine because it has a double washing cycle. If you were to notice that the salesperson smiled at you and was well dressed, this wouldn't add to the quality of the original argument, but unfortunately it does for those who are influenced by style over substance, as most of us are.

Straw Man

You commit the straw man fallacy whenever you attribute an easily refuted position to your opponent, one that the opponent wouldn't endorse, and then proceed to attack the easily refuted position believing you have undermined the opponent's actual position. If the misrepresentation is on purpose, then the straw man fallacy is caused by lying.

Example (a debate before the city council):

Opponent: Because of the killing and suffering of Indians that followed Columbus's discovery of America, the City of Berkeley should declare that Columbus Day will no longer be observed in our city.

Speaker: This is ridiculous, fellow members of the city council. It's not true that everybody who ever came to America from another country somehow oppressed the Indians. I say we should continue to observe Columbus Day, and vote down this resolution that will make the City of Berkeley the laughing stock of the nation.

The speaker has twisted what his opponent said; the opponent never said, nor even indirectly suggested, that everybody who ever came to America from another country somehow oppressed the Indians.

Stereotyping

Using stereotypes as if they are accurate generalizations for the whole group is an error in reasoning. Stereotypes are general beliefs we use to categorize people, objects, and events; but these beliefs are overstatements that shouldn't be taken literally. For example, consider the stereotype "She’s Mexican, so she’s going to be late." This conveys a mistaken impression of all Mexicans. On the other hand, even though most Mexicans are punctual, a German is more apt to be punctual than a Mexican, and this fact is said to be the "kernel of truth" in the stereotype. The danger in our using stereotypes is that speakers or listeners will not realize that even the best stereotypes are accurate only when taken probabilistically. As a consequence, the use of stereotypes can breed racism, sexism, and other forms of bigotry.

Example:

German people aren't good at dancing our sambas. She's German. So, she's not going to be any good at dancing our sambas.

This argument is deductively valid, but it's unsound because it rests on a false, stereotypical premise. The grain of truth in the stereotype is that the average German doesn't dance sambas as well as the average South American, but to overgeneralize and presume that ALL Germans are poor samba dancers compared to South Americans is a mistake called "stereotyping."

Stacking the Deck

See Suppressed Evidence and Slanting.

Specificity

Drawing an overly specific conclusion from the evidence. A kind of jumping to conclusions.

Example:

The trigonometry calculation came out to 35,005.6833 feet, so that's how wide the cloud is up there.

Special Pleading

Special pleading is a form of inconsistency in which the reasoner doesn't apply his or her principles consistently. It is the fallacy of applying a general principle to various situations but not applying it to a special situation that interests the arguer even though the general principle properly applies to that special situation, too.

Example:

Everyone has a duty to help the police do their job, no matter who the suspect is. That is why we must support investigations into corruption in the police department. No person is above the law. Of course, if the police come knocking on my door to ask about my neighbors and the robberies in our building, I know nothing. I'm not about to rat on anybody.

In our example, the principle of helping the police is applied to investigations of police officers but not to one's neighbors.

Sorites

See Line-Drawing.

Smokescreen

This fallacy occurs by offering too many details in order either to obscure the point or to cover-up counter-evidence. In the latter case it would be an example of the fallacy of suppressed evidence. If you produce a smokescreen by bringing up an irrelevant issue, then you produce a red herring fallacy. Sometimes called clouding the issue.

Example:

Senator, wait before you vote on Senate Bill 88. Do you realize that Delaware passed a bill on the same subject in 1932, but it was ruled unconstitutional for these twenty reasons. Let me list them here.... Also, before you vote on SB 88 you need to know that .... And so on.

There is no recipe to follow in distinguishing smokescreens from reasonable appeals to caution and care.

Smear Tactic

A smear tactic is an unfair characterization either of the opponent or the opponent's position or argument. Smearing the opponent causes an ad hominem fallacy. Smearing the opponent's argument causes a straw man fallacy.

Small Sample

This is the fallacy of using too small a sample. If the sample is too small to provide a representative sample of the population, and if we have the background information to know that there is this problem with sample size, yet we still accept the generalization upon the sample results, then we commit the fallacy. This fallacy is the fallacy of hasty generalization, but it emphasizes statistical sampling techniques.

Example:

I've eaten in restaurants twice in my life, and both times I've gotten sick. I've learned one thing from these experiences: restaurants make me sick.

How big a sample do you need to avoid the fallacy? Relying on background knowledge about a population's lack of diversity can reduce the sample size needed for the generalization. With a completely homogeneous population, a sample of one is large enough to be representative of the population; if we've seen one electron, we've seen them all. However, eating in one restaurant is not like eating in any restaurant, so far as getting sick is concerned. We cannot place a specific number on sample size below which the fallacy is produced unless we know about homogeneity of the population and the margin of error and the confidence level.

Slippery Slope

Suppose someone claims that a first step (in a chain of causes and effects, or a chain of reasoning) will probably lead to a second step that in turn will probably lead to another step and so on until a final step ends in trouble. If the likelihood of the trouble occurring is exaggerated, the slippery slope fallacy is committed.

Example:

Mom: Those look like bags under your eyes. Are you getting enough sleep?

Jeff: I had a test and stayed up late studying.

Mom: You didn't take any drugs, did you?

Jeff: Just caffeine in my coffee, like I always do.

Mom: Jeff! You know what happens when people take drugs! Pretty soon the caffeine won't be strong enough. Then you will take something stronger, maybe someone's diet pill. Then, something even stronger. Eventually, you will be doing cocaine. Then you will be a crack addict! So, don't drink that coffee.

The form of a slippery slope fallacy looks like this:

A leads to B.
B leads to C.
C leads to D.
...
Z leads to HELL.
We don't want to go to HELL.
So, don't take that first step A.

Think of the sequence A, B, C, D, ..., Z as a sequence of closely stacked dominoes. The key claim in the fallacy is that pushing over the first one will start a chain reaction of falling dominoes, each one triggering the next. But the analyst asks how likely is it really that pushing the first will lead to the fall of the last? For example, if A leads to B with a probability of 80 percent, and B leads to C with a probability of 80 percent, and C leads to D with a probability of 80 percent, is it likely that A will eventually lead to D? No, not at all; there is about a 50- 50 chance. The proper analysis of a slippery slope argument depends on sensitivity to such probabilistic calculations. Regarding terminology, if the chain of reasoning A, B, C, D, ..., Z is about causes, then the fallacy is called the Domino Fallacy.

Sharpshooter's

The sharpshooter's fallacy gets its name from someone shooting a rifle at the side of the barn and then going over and drawing a target and bulls eye concentrically around the bullet hole. The fallacy is caused by overemphasizing random results or making selective use of coincidence. See the Fallacy of Selective Attention.

Example:

Psychic Sarah makes twenty-six predictions about what will happen next year. When one, but only one, of the predictions comes true, she says, "Aha! I can see into the future."

Self-Fulfilling Prophecy

The fallacy occurs when the act of prophesying will itself produce the effect that is prophesied, but the reasoner doesn't recognize this and believes the prophesy is a significant insight.

Example:

A group of students are selected to be interviewed individually by the teacher. Each selected student is told that the teacher has predicted they will do significantly better in their future school work. Actually, though, the teacher has no special information about the students and has picked the group at random. If the students believe this prediction about themselves, then, given human psychology, it is likely that they will do better merely because of the teacher's making the prediction.

The prediction will fulfill itself, so to speak, and the students commit the fallacy. This fallacy can be dangerous in an atmosphere of potential war between nations when the leader of a nation predicts that their nation will go to war against their enemy. This prediction could very well precipitate an enemy attack because the enemy calculates that if war is inevitable then it is to their military advantage not to get caught by surprise.

Selective Attention

Improperly focusing attention on certain things and ignoring others.

Example:

Father: Justine, how was your school day today? Another C on the history test like last time?
Justine: Dad, I got an A- on my history test today. Isn't that great? Only one student got an A.
Father: I see you weren't the one with the A. And what about the math quiz?
Justine: I think I did OK, better than last time.
Father: If you really did well, you'd be sure. What I'm sure of is that today was a pretty bad day for you.

The pessimist who pays attention to all the bad news and ignores the good news thereby commits the fallacy of selective attention. The remedy for this fallacy is to pay attention to all the relevant evidence. The most common examples of selective attention are the fallacy of Suppressed Evidence and the fallacy of Confirmation Bias. See also the Sharpshooter's Fallacy.