Andy Crawford | Reborn in PHP

Logical Fallacy

Published June 2014 | By Andy Crawford

The Enemy Of Reasoned Debate

When discussion and debate is conducted properly it should lead to logical conclusion. However debate can often become muddied by people using what is known as 'logical fallacy'. Logical fallacy is often used to bolster ones own argument or prejudice, usually when ones own argument is very weak.

We should always watch out for the use of 'logical fallacy' as it can detract from the debate, 'muddy the waters', and lead to poor outcomes. If not spotted, its use can lead to illogical conclusions being drawn and poor decisions being made.

Some Examples of Logical Fallacy

Ad Hominem
Attacking an opponent personally so as to undermine their argument.

Using double meaning or ambiguity in words to mislead or misrepresent the truth.

Using an isolated example rather than a sound argument or evidence.

Appeal to Authority
Using authority to claim truth.

Appeal to Emotion
An attempt to create an emotional response instead of using a valid reasoning.

Appeal to Nature
Claiming that if something is natural it is valid.

Appealing to popularity as a form of validation.

Black or White - False Dilemma - Binary Thinking
Claiming only two alternatives exist, when there are more possibilities.

Burden of Proof
Claiming that something must be disproved by others. Claiming that if it cannot be disproved then it must be true.

Composition - Division
The assumption that one thing must be applied to all.

False Cause
Where two things occur, it is claimed that one is the cause of the other.

Fallacy Fallacy
Claiming the argument must be wrong because it was poorly made or a fallacy was used when making it.

Gambler's Fallacy
To claim that statistically independent phenomena will affect future outcomes. For example believing that if you were to flip a coin 10 times and the outcome were heads every time, that the chances of heads/tails on the 11th flip becomes something other than 50:50.

Judging something by where it comes from or who it came from rather than on its own merit.

Loaded Question
Asking a question which implies guilt no matter how it is answered.

Middle Ground
The claim that the middle point between two extremes must be correct.

No True Scotsman
Appealing to an example of purity to dismiss criticism or flaws. Some Scotsman put sugar on their porridge. Ah but no true Scotsman would ever put sugar on their porridge.

Personal Incredulity
If something is not understood, it is claimed it is not true.

Slippery Slope
If we allow A to happen, eventually Z will happen, therefore A should not happen.

Special Pleading
Moving the argument or making exceptions when proven to be wrong

The opponent's argument is exaggerated or misrepresented in order to undermine it.

Tu Tuoque
Avoiding the argument by criticising the accuser of something else.

Texas Sharpshooter
Finding a pattern to fit a presumption. Like shooting at a wall and then painting on a target where most of the most bullets hit.

Use of logical fallacy can be inadvertent, but it can also be used deceitfully. It is often used by people who are insistent on getting their own way.