The Art of Debating
Below, I have compiled a list of logical fallacies for you to read, learn, and use in your debates! Of course, it's not mandatory... however, with these tools at hand, you can become strong in the art of debating.
*note* I have gone through this list and have shortened/simplified them for you.
Logical Fallacies and the Art of Debating by California State University of Northridge
Argumentum ad antiquitatem (the argument to antiquity or tradition).
This is the familiar argument that some policy, behavior, or practice is right or acceptable because "it's always been done that way."
Example: "Every great civilization in history has provided state subsidies for art and culture!"
But that fact does not justify continuing the policy.Because an argumentum ad antiquitatem is easily refuted by simply pointing it out, in general it should be avoided. But if you must make such an argument -- perhaps because you can't come up with anything better -- you can at least make it marginally more acceptable by providing some reason why tradition should usually be respected.
Argumentum ad hominem (argument directed at the person).
This is the error of attacking the character or motives of a person who has stated an idea, rather than the idea itself.
Example(s):
"The members of the opposition are a couple of fascists!"
"You're clearly ignorant."
"We all know Nixon was a liar and a cheat, so why should we believe anything he says?"
However, it is also possible to restate many ad hominem arguments so as to redirect them toward ideas rather than people, such as by replacing "My opponents are fascists" with "My opponents' arguments are fascist." And that is acceptable.
Argumentum ad ignorantiam (argument to ignorance).
This is the fallacy of assuming something is true simply because it hasn't been proven false.
For example, someone might argue that global warming is certainly occurring because nobody has demonstrated conclusively that it is not. But failing to prove the global warming theory false is not the same as proving it true.
Argumentum ad logicam (argument to logic). This is the fallacy of assuming that something is false simply because a proof or argument that someone has offered for it is invalid; this reasoning is fallacious because there may be another proof or argument that successfully supports the proposition. This fallacy often appears in the context of a straw man argument.
Argumentum ad misericordiam (argument or appeal to pity). The English translation pretty much says it all.
Example: "Think of all the poor, starving Ethiopian children! How could we be so cruel as not to help them?"
The problem with such an argument is that no amount of special pleading can make the impossible possible, the false true, the expensive costless, etc.Argumentum ad nauseam (argument to the point of disgust; i.e., by repitition). This is the fallacy of trying to prove something by saying it again and again. But no matter how many times you repeat something, it will not become any more or less true than it was in the first place. Of course, it is
not a fallacy to state the truth again and again; what is fallacious is to expect the repetition alone to substitute for real arguments.
Argumentum ad numerum (argument or appeal to numbers). This fallacy is the attempt to prove something by showing how many people think that it's true. But no matter how many people believe something, that doesn't necessarily make it true or right.
Example: "At least 70% of all Americans support restrictions on access to abortions."
Well, maybe 70% of Americans are wrong!Argumentum ad populum (argument or appeal to the public). This is the fallacy of trying to prove something by showing that the public agrees with you. For an example, see above. This fallacy is nearly identical to argumentum ad numerum.
Argumentum ad verecundiam (argument or appeal to authority). This fallacy occurs when someone tries to demonstrate the truth of a proposition by citing some person who agrees, even though that person may have no expertise in the given area.
Circulus in demonstrando (circular argument). Circular argumentation occurs when someone uses what they are trying to prove as part of the proof of that thing.
Example: "Marijuana is illegal in every state in the nation. And we all know that you shouldn't violate the law. Since smoking pot is illegal, you shouldn't smoke pot. And since you shouldn't smoke pot, it is the duty of the government to stop people from smoking it, which is why marijuana is illegal!"
Circular arguments appear a lot in debate, but they are not always so easy to spot as the example above. They are always illegitimate, though, and pointing them out in a debate round looks really good if you can do it.
Complex question. A complex question is a question that implicitly assumes something to be true by its construction.
Example: "Have you stopped beating your wife?" A question like this is fallacious only if the thing presumed true (in this case, that you beat your wife) has not been established.
c** hoc ergo propter hoc (with this, therefore because of this). This is the familiar fallacy of mistaking correlation for causation -- i.e., thinking that because two things occur simultaneously, one must be a cause of the other.
Example: "President Clinton has great economic policies; just look at how well the economy is doing while he's in office!"
The problem here is that two things may happen at the same time merely by coincidence, or the causative link between one thing and another may be lagged in time, or the two things may be unconnected to each other but related to a common cause.
Dicto simpliciter (spoken simply, i.e., sweeping generalization). This is the fallacy of making a sweeping statement and expecting it to be true of every specific case -- in other words, stereotyping.
Example: "Women are on average not as strong as men and less able to carry a gun. Therefore women can't pull their weight in a military unit." The problem is that the sweeping statement may be true (on average, women are indeed weaker than men), but it is not necessarily true for every member of the group in question (there are some women who are much stronger than the average).
Nature, appeal to. This is the fallacy of assuming that whatever is "natural" or consistent with "nature" (somehow defined) is good, or that whatever conflicts with nature is bad.
Example: "Marijuana is natural, while cigarettes are man-made. That means that smoking pot is healthier than smoking cigarettes." Just because it's natural doesn't mean it's good for you.
Naturalistic fallacy. This is the fallacy of trying to derive conclusions about what is right or good (that is, about values) from statements of fact alone. This is invalid because no matter how many statements of fact you assemble, any logical inference from them will be another statement of fact, not a statement of value.
Example:"This medicine will prevent you from dying" immediately leads to the conclusion, "You should take this medicine." But this reasoning is invalid, because the former statement is a statement of fact, while the latter is a statement of value.
To reach the conclusion that you ought to take the medicine, you would need at least one more premise: "You ought to try to preserve your life whenever possible."
Non Sequitur ("It does not follow"). This is the simple fallacy of stating, as a conclusion, something that does not strictly follow from the premises.
Example: "Racism is wrong. Therefore, we need affirmative action." Obviously, there is at least one missing step in this argument, because the wrongness of racism does not imply a need for affirmative action without some additional support (such as, "Racism is common," "Affirmative action would reduce racism," "There are no superior alternatives to affirmative action," etc.).
Petitio principii (begging the question). This is the fallacy of assuming, when trying to prove something, what it is that you are trying prove. For all practical purposes, this fallacy is indistinguishable from circular argumentation.
Example:"The fact that we believe pornography should be legal means that it is a valid form of free expression. And since it's free expression, it shouldn't be banned," that would be begging the question.
Post hoc ergo propter hoc (after this, therefore because of this). This is the fallacy of assuming that A caused B simply because A happened prior to B.
Example: "Most rapists read pornography when they were teenagers; obviously, pornography causes violence toward women." The conclusion is invalid, because there can be a correlation between two phenomena without one causing the other. Often, this is because both phenomena may be linked to the same cause. In the example given, it is possible that some psychological factor -- say, a frustrated sex drive -- might cause both a tendency toward sexual violence and a desire for pornographic material, in which case the pornography would not be the true cause of the violence.
Red herring. This means exactly what you think it means: introducing irrelevant facts or arguments to distract from the question at hand.
Example, "The opposition claims that welfare dependency leads to higher crime rates -- but how are poor people supposed to keep a roof over their heads without our help?"
Slippery slope. A slippery slope argument is not always a fallacy. A slippery slope fallacy is an argument that says adopting one policy or taking one action will lead to a series of other policies or actions also being taken, without showing a causal connection between the advocated policy and the consequent policies.
Example: "If we legalize marijuana, the next thing you know we'll legalize heroin, LSD, and crack cocaine." This slippery slope is a form of non sequitur, because no reason has been provided for why legalization of one thing leads to legalization of another. Tobacco and alcohol are currently legal, and yet other drugs have somehow remained illegal.
There are a variety of ways to turn a slippery slope fallacy into a valid (or at least plausible) argument. All you need to do is provide some reason why the adoption of one policy will lead to the adoption of another. For example, you could argue that legalizing marijuana would cause more people to consider the use of mind-altering drugs acceptable, and those people will support more permissive drug policies across the board.
Tu quoque ("you too").
This is the fallacy of defending an error in one's reasoning by pointing out that one's opponent has made the same error. An error is still an error, regardless of how many people make it.
Example, "They accuse us of making unjustified assertions. But they asserted a lot of things, too!"
