The Lagoon TechMy little blog in Cyberspace.

This logical fallacy is known as “appeal to accomplishment”. This is when Person A agrees or disagrees with given information, based upon the personal accomplishments (or credentials) of Person B who gave the information. Information is true or false, regardless if the person who gave the information is well versed in a particular field.

For example, Greg says that getting too much sun on your skin may cause skin cancer. Tyler then responds, dismissing what Greg said because Greg is “not a doctor”.

Now does Greg not being a doctor change the fact that you may get skin cancer being exposed to too much sun? Of course not. However, Tyler decided to dismiss this information just because Greg is “not a doctor”. He could have at least researched what Greg told him, before deciding to dismiss it.

Summary: Appeal to accomplishment is nothing more than agreeing or disagreeing with what someone said based upon their credentials or personal experience, not if the information itself is correct. Obviously, this is not a good idea and making use of this logical fallacy will eventually cause you trouble.

This logical fallacy is known as “appeal to anecdote”. What exactly is “anecdotal evidence”? It is someone’s personal testimony of a particular event. It contains no scientific data, just someone’s word on a matter.

When you read someone’s anecdote and use it as proof, you would be committing the “appeal to anecdote” fallacy. You are saying something is true, just because someone else claims that is the case.

The Internet is full of people who give anecdotal testimonies as “proof” of their claims. Unless you were there with the person at the time of the event, or they present detailed evidence, there is no way to determine if they are accurately recalling the facts. This is assuming the person is telling the truth to begin with.

Here is an example. You go to a website to view information about the common cold. While on there, you decide to read the comment section.

A guy named Phil posts a comment saying he is a “very healthy individual” and “has never caught a cold before”. (Now personally I would say Phil is lying. Sure, there is a (very) small chance of his statement being true, but I would not bet on it.)

You take Phil’s comment and start going around telling others “there are people who can never get the common cold”. You would be committing the “appeal to anecdote” fallacy. You are saying something is true, because someone else claimed that is what happened to them.

Phil’s comment was not “proof” of anything. He presented no evidence of his claim. He could have had a cold (multiple times) and thought it was just allergies. If that is the case, he is relaying incorrect information based upon a bad assumption…and now you are relaying his bad information, based upon his bad assumption too. What a situation to be in!

Something to keep in mind. People are not talking face to face when using web forums, instant messaging, posting a comment, etc. That fact tends to make people feel more comfortable exaggerating information – or just plain making up information – about themselves or others in their anecdotes. No one is around to verify their information, much less “punish” them for lying.

This happens a whole lot more on the Internet than people realize, especially if the anecdote someone gives strokes their own ego (e.g., Someone claims they made $20,000 trading stocks. However, the person only made $6,000 trading stocks, not $20,000).

Always verify information you receive online (when possible) and use common sense when reading someone’s anecdote. Not everyone lies on the Internet, but it sure makes it a whole lot easier for the ones that do to get away with it.

Summary: An anecdote is someone’s personal testimony of a particular event. Using an anecdote to prove a point is a logical fallacy, since there is no evidence given, just someone’s word on a matter.

What exactly is circular reasoning? Circular reasoning is when you attempt to make an argument by assuming what you are trying to prove is already true. In other words, instead of using A to prove B true, you are using B – itself – to prove B true. This is a bad way to argue.

Here is an example. Larry tells Mike about a new spray cleaner that will clean anything on any surface. Mike is intrigued and asks Larry how he knows the new cleaner will clean anything. Larry explains to Mike it will clean anything because it says so on the label.

Notice what happened? Larry used the bottle’s label to prove that the label is true. This is not a proper way to argue, since you are not proving anything. At best, you are showing you have faith the label is telling the truth.

This may be a surprise to you, but circular reasoning is not always a logical fallacy. There are arguments made with circular reasoning that are valid and can be applied without issue.

One example of a good circular argument is the following: “If we did not have laws of logic, we could not make any arguments. Since we all can make arguments, laws of logic must exist.”

This circular argument is valid. Laws of logic must be assumed to be true, otherwise no arguments could ever be made. If you were to argue the laws of logic do not exist, you would be using the “laws of logic” to claim that the laws of logic do not exist. That does not make any sense.

Summary: Circular reasoning is when you attempt to make an argument by assuming what you are trying to prove is already true. However, there are times when circular arguments are valid and make sense to use in a discussion.

Let’s first get a definition of “ad hominem”.

The Merriam-Webster dictionary defines “ad hominem” as: marked by or being an attack on an opponent’s character rather than by an answer to the contentions made

This logical fallacy is when someone directs their argument at the person who gave the information, instead of the person’s position in the argument.

For example, Martin tells Kyle he thinks sports cars do not have good gas mileage, and people are better off not buying them. Kyle responds with calling Martin an idiot and tells him he is wrong.

You see what happened? Kyle did not give any countering information to show Martin being incorrect. Instead Kyle disrespected Martin while making himself look silly. Kyle should have not said anything, since he really didn’t anyway.

Summary: “ad hominem” arguments are nothing more than personally attacking someone, instead of attacking their position in an argument. When someone commits this logical fallacy, it is a good sign they have no real argument to give.