Some Common Logical Fallacies (and How They Corrupt Reasoned Debate)

In simple terms, logical fallacies are errors in reasoning which lead to false conclusions. If they go unrecognized and unchallenged, they corrupt rational thinking and reasoned debate.

Sometimes these errors of thinking occur by mistake. Humans are pattern–seeking beings. We tend to see patterns even when there are none.

We Will Write a Custom Essay Specifically
For You For Only $13.90/page!

order now
  • For instance, people looked up into the sky and saw a random array of stars and decided it looked like a dipper.
  • Another example is a misunderstanding of mathematics and science, particularly probability. Coincidences may be far more common than people think.

Other times, charlatans deliberately use tricks to sell lies. Their reasoning seems to make sense, but you could be conned if you cannot see the logical fallacies in their statements.

Here are some of the logical fallacies you are likely to encounter most often. There are so many logical fallacies that I didn’t have space for all of them.

This one may be the most common one of all. Someone will attempt to refute a statement by attacking the person who made the statement.

  • Sometimes the attacker will just hurl insults. The person under attack will have his intelligence insulted—he will be called stupid, a moron, a dupe, a fool, etc.
  • Or maybe the attacker will engage in character assassination. The person under attack will be called corrupt, racist, a well-known liar, etc.
  • In political discussions, the word “fascist” is bandied about, and it is most often used inappropriately. The attacker probably doesn’t even know what fascist means– all he knows that it is an emotionally-loaded term with negative connotations.

Note: It does not matter if the person is being accurately described—perhaps he really is a moron, or a scoundrel, or a fascist. And it does not mean that we should not consider the trustworthiness of the source of a claim. However, it is important to realize that the claim itself is NOT being addressed in ad-hominem attacks. A “bad” person may be making a true claim.

“Guilt by association” is another ad-hominem approach. A good example of this was one of the attempts to smear Barack Obama during his 2008 campaign for president. Obama was attacked for having had a prior association with Bill Ayers, a man who was a member of the Weather Underground in the 1970’s, but in 2008 he was a solid citizen and businessman The argument went that since Ayers had once committed a terrorist act and since he had once hosted an event years earlier to promote Obama’s candidacy for the Illinois Senate, Obama must be a terrorist.

Again, guilt-by association is not always wrong. Someone who associates with mob bosses, for instance, may actually be corrupt. However, arguing about associations means that the facts of the claim are being ignored.

The attacker will say that a prominent and/or respected person or group believes a certain claim, so therefore it must be true.

“The Pope said that climate change is endangering mankind, so it must be true.”

“The AMA (The American Medical Association) is against the Republican Health Care bill, so it should not be passed.”

“Franklin Graham, the well-known religious leader, opposes marriage equality, so it must be wrong.”

(For the record, I believe the Pope and the AMA are right, but that does not mean their claims should automatically be accepted. They still need to present facts.)

The reverse side of this attack is dismissing a claim because the person making the claim is not an authority or does not have credentials in the field.

For example, someone might say a man can’t talk about misogyny or abortion because he is not a woman. Or a white person can’t talk about racism because he is not black.

Another example is saying a person is not qualified to speak on a subject because he is not a recognized expert in the field.

  • An actor shouldn’t talk about politics
  • A scientist shouldn’t talk about religion.

The attacker is ignoring the possibility that someone who is prominent in one field could also have a lot of knowledge in another field.

Another type of appeal to authority is to claim that since large groups of people believe it, it must be true.

Sorry, “majority rule” is not how we determine facts. Remember, everybody once believed that the earth was flat and that spontaneous generation accounted for maggots.

“The overwhelming majority of climate scientists say climate change is being caused by human actions, so it must be true.”

“Christianity is the world’s largest religion, so it must be the one true religion.”

For the record, I believe the first statement because it is backed up with evidence; I don’t believe the second statement because there is no evidence that it is true, and there is not even any way to prove it is true.

You’ve heard the phrase, “Figures don’t lie, but liars figure.” Sometimes your opponent will deliberately misuse statistics to confuse you.

Other times, your opponent will dazzle you with charts, numbers, and statistics with the aim of overwhelming you. Usually none of his data is actually relevant to the questions. Sometimes the data is not even correct.

A person will make a claim based on insufficient information, often called “jumping to a conclusion.”

“Today I saw a senior citizen make a turn without signaling. All old people are bad drivers.”

“Some black young men are in a gang. All black young men are thugs.”

“I bought an apple in this store and it was mushy inside. I won’t shop there again because all their produce is rotten.”

This means “a part taken as the whole”, but I would call it “use the whole to obscure the part” or maybe “see the forest and hide the tree.” It is done to divert attention away from, and even to ridicule, a particular case

“We must save the whales.” “No, we must save all the creatures in the sea.”

“Black lives matter.” “No, all lives matter.”

The second half of each of the above examples is, of course, true, but they do not negate the first half of the statements. They only distract from it.

This is an augment that tries to associate one action with another obviously really bad action. The claim is that the first action will be the start of a slide into other actions. I sometimes call this one “taking things to an absurd conclusion”. The attacker thinks of the absolutely worse outcome, and then says it will inevitably occur as a result of allowing the first action.

In the following three examples, there is no proof that the first action inevitably leads to the second action

“If abortion is made legal, then infanticide will be next.”

“If we allow same-sex marriage, next we will have people marrying their dogs.”

“If marijuana is legal, people will become heroin addicts.”

It’s a Latin phrase for “after this, therefore, because of this.” It means if Event B occurs after event A, A must have caused B.

“I prayed my cancer would be cured and now I am cancer free. God answered my prayers.”

The cure happened after the prayer, but that does not mean that prayer cured the cancer. Many other people with cancer also prayed, and some of them died.

Correlation is not causation. Sometimes there are spurious correlations– two things are associated with each other, but one did not cause the other. A third thing caused both of them.

“Studies show that married people are happier than single people. If you are single and unhappy, you should get married and you will be happy.”

“Ever since Mayor X took office, crime has been down in his city. It’s because of his tough law-and-order stance.”

In the first example, there is a correlation between happiness and marriage, but perhaps this occurs because happy people are more likely to get married. (Who wants to marry a sour-puss?)

In the second example, perhaps unemployment dropped because a recession ended and this created more jobs for people aand thus there were fewer unemployed people and less crime.

The problem is stated as if there are only two choices. But often there are many other choices.

“Either we have school voucher programs or we have failing children in public schools. Which do you want?”

The problem of children failing in school does not lend itself to either/or solutions. Perhaps smaller classroom size in public schools is the answer. Perhaps paying teachers more so the best most-experienced teachers will not quit teaching for better paying jobs is the answer. Perhaps an after-school tutoring program is the answer.

This one compares a small thing to a really big thing and declares them equal.

  • President Obama said: “If you like your health insurance, you can keep it.”
  • Donald Trump said: “Obama is the founder of ISIS.”

So are Obama and Trump both liars? False equivalency! Obama said something that he believed to be true when he said it, but it didn’t work out as he predicted it would. Trump told a giant whopper of a lie that had absolutely no basis in fact.

When someone can’t defend his position, he will restate the issue to something he can defend. Then he’ll knock down this “straw man.”

“You are against the death penalty. You want to set murderers loose to kill again.” (Now the argument is no longer about what punishment should be meted out for murder, but whether or not murders should be allowed to run amok in society.)

“You say atheists are as moral as anyone else. Stalin was an atheist and he killed millions of people.” (Now the argument is no longer about secular morality, but about a Russian dictator.)

When it is impossible to know the truth of a position, someone will claim that therefore his position must be treated as proven.

“You can’t prove how the universe came into existence, so God did it.”

In some cases, someone will claim that an argument that has even one unproven point means that the whole argument is false.

“You can’t prove how life first arose, so everything that has been proven about evolution is false, and God created the universe in six days just like it says in Genesis.”

This argument merely restates the premise in different words and then claims the second statement proves the first.

“Donald Trump is the best leader for America because he got elected. Getting elected proves he is the best leader.”

A person starts with a conclusion and then searches for facts to prove it. Facts should always precede a conclusion.

A person will say “This is how it has always been done.” Perhaps, but does that mean the usual way is the best way?

Sometimes a person will start with a false statement that he takes as a “given.” However, the initial premise is not always true, and if it is false, everything else that follows must be called into questions.

“The wealthy are the job creators, so we must cut their taxes and the wealth will trickle down to the middle class and working class.”

If the first part of the statement is false (as I believe it is), the rest of the statement has no validity.

Lastly, here are some tricks an opponent might use when he has absolutely no way to defend his positions.

The Non-Sequitur

This is from Latin and it means “does not follow. “ Usually when you ask a politician or his surrogate a question, you don’t get a straight answer. He dances around the topic.

Q. “Do you support the Trump-Ryan health care bill?”

A: “I tell you what I support. I support freedom. Every American should be able to have health care of his choice. Blah blah blah.”

The questioner never gets a direct answer to a simple question.

The Red Herring Defense

Politicians love to use this one. They just pivot to an unrelated topic; they don’t even bother to dance around the original topic.

Q: “Is ending poverty in America important?”

A: “I’ll tell you what is important. Ending terrorism. Blah, blah blah.”

Kelly Ann Conway, Trump’s campaign manager and now one of his White House advisers, is the master of this one.


This is the act of taking a complex question and reducing it to very simple terms, sometimes down to a slogan.

Q. “What do we need to do to bring economic gains to everyone?”

A: “We need to make America great again.”

The Affective Defense

This one is like a punch to the gut. It is intended to make you feel like you are a terrible person.

“I have every right to my beliefs. You need to respect my beliefs.”

This person is attempting to conflate a reasoned refutation of a position with a personal attack.

The Get-Over-It Defense

If you try to argue about something, you are essentially dismissed and told to stop being a “cry-baby.” The reasons you hoped to give for your point of view won’t even be heard.

Q. “Will the election of Donald Trump have dire consequences for the United States.”

A. “Trump won. Democrats lost. Get over it.”

You will frequently see what I call “the song and dance.” I see it a lot when politicians and political surrogates are being interviewed on TV.

They will talk very fast, bring up multiple topics, and use every logical fallacy and defense they can manage to throw in. The interviewer is overwhelmed. He can’t respond to everything, and consequently a lot of false information remains unchallenged.