“7 Common Logical Mistakes People Make.”

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I love communicating with people and sharing ideas with them. And most of the conversations are
fulfilling and productive and we both end up learning from each other. However, there are times
when I find some glaring logical fallacies in our language which hinder communication and stunt intellectual growth.I do not mind them when we are talking informally, but in any serious conversation logical fallacies can create major misunderstandings.Those are the ghosts worthy of exorcism. Here are some common logical fallacies which I observed.

(1) “Statistically most of the Indian policemen have mustache. Mohan is an Indian policeman hence he should have a mustache.”
This sort of argument suffers from a basic statistical mistake. Statistics talks about things in bulk. It does not say anything about one particular case. Hence to draw particular conclusions from statistical data is fallacious. Mohan might be an Indian policeman but you cannot infer from that that he must have a mustache.

(2) “I found evidence of no disease.”
There is no such thing like that in medicine, or in real life.Actually the statement should be :”I found no evidence of disease” .Evidence of no disease is totally different from no evidence of disease.Absence is totally different from presence ,logically. If I do not see you in KLCC mall I cannot conclude that you were not there. But if I did see you in KLCC mall then I can safely conclude that you were there. Not seeing does not constitute a proof of absence.

(3)”All what you say is wrong because you are a freak.”
It is a very common mistake in arguments, and it is called ad hominum. Instead of addressing the argument you address the person who is making the argument.Conversely, you can also say something like this: He is an expert therefore he must be right. This argument is equally invalid.

(4)”Are you still beating your wife?”
Whether you say yes or no, it presupposes that you have a wife and in the past you used to beat her up. These are loaded questions which assume some unproved facts embedded in the question. Before these kind of questions are answered the hidden assumptions are to be addressed first.

(5)”Bad luck befalls me every time I sneeze.My sneezing must be causing me bad luck.”
It is a classic case of confusion between correlation and causation. If event ‘A’ happens whenever ‘B’ happens, it doesn’t mean that ‘A’ is caused by ‘B’. It is equally possible that ‘B’ is caused by ‘A’. Or that both ‘A’ and ‘B’ are caused by a third cause ‘Z’.May be you are sick and hence you sneeze and end up fumbling.

(6) “All policemen wear brown dress. I saw a man running wearing brown dress. He must be a policeman.”
Wrong logic. ‘A’ implies ‘B’, does not mean that ‘B’ also implies ‘A’. If all policemen wear brown dress does not mean that all who wear brown dress are policemen. However, the inverse implication is valid for negatives. Means if ‘A’ implies ‘B’, the it is also true that not ‘B’ implies not ‘A’. In the policeman case it is alright to say that I saw a man who was not wearing a brown dress then it means that he was not a policeman.

(7)”Interviewer:Are Atoms and RSS same?You: No they are not.Interviewer: Wrong answer they are the same.”
The thing is that if two things have a different technical name then inherently there is some difference between them. If they were not different there wouldn’t be two different terms for them in the technical jargon. So, until some context is given, whether two things are different is an erroneous question to ask.(Somebody actually asked me the former question).Are apples and oranges the same? Of course not. But you can call them the same if you say that they both are fruits. Hence, their same-ness comes about only after you give a context,not before it.

Now a bonus logical fallacy:

“They are an ideal couple. They have been together for 20 years now.”

These kind of statements are logically incomplete.They statement do not mean anything until you answer the question:”Were they happy or miserable together?”  For example look at the following sentences: “I went to Paris because.” ” He has the plane tickets hence.”

The above sentences are grammatically incomplete and hence jarring. Likewise, sentences which are logically incomplete are jarring as well. And are detriments to any meaningful conversation.They should be done away with as soon as possible.

What are some of the logical fallacies you have encountered? Do put them in the comment section to enlighten us all.

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Tags: Fallacy, Informal Logic, Loaded question, Luck, Philosophy, Philosophy of Logic, Statistics