Logical Fallacies



A persuasive argument consists of two main components: a claim and reasons for that claim. Neither a claim without reasons nor reasons without a claim is an argument. Sometimes, the main idea of an essay can be expressed as follows:

CLAIM = ________________________________________


  • Reason 1: ____________________________
  • Reason 2: ____________________________
  • Reason 3: ____________________________

In persuasive essays, the more convincing your argument, the more successful you will be in challenging the thinking of your reader and even changing his or her mind.

HOWEVER, there are some strategies you should avoid, in order to be as convincing as possible. These persuasive strategies may work on occasion, but they are not effective in convincing a thoughtful audience.

Logical Fallacies - Ineffective Reasoning Methods



While writing persuasive essays, avoid logical fallacies (reasoning errors that makes a conclusion unsound) or your arguments will not be taken seriously. A fallacy may or may not be intentional, and it may or may not fool the audience.

Learning how to recognize these in print or media texts is essential to your ability to make good decisions.

Following are a few examples of common logical fallacies:

Ad Hominem: ('to the man' or name calling)


Parents never let you do anything fun because they are mean.

Attacking the character of a person or name-calling does not address the main argument or problem. A parent's meanness may be irrelevant to the activity in which you wish to participate.


Bandwagon: everyone is doing something, and so should you


But Mom, everyone is doing it.
The majority of people like to drink pop; therefore, you should too.

This kind of argument encourages the listener to accept the argument because it is popular and not because it is right.

False cause: inaccurate or unproven cause-effect


Turns a coincidence or a correlation into a cause.
eg. When the rooster crows, the sun rises; therefore, the rooster's crow causes the sun to rise.

Sometimes the cause and effect are not connected. The rooster crows during the day, but the sun does not rise again. The connection between the sun rising when the rooster crows is incorrect. Just because events occur together does not mean necessarily that a cause-effect relationship exists.

 

Circular Reasoning: begging the question




 
"He's a jerk because he is not nice."
X is true because of Y. Y is true because of X.

Simply repeating what has already been said does not settle an argument.



Logical fallacies are interesting! We are not going to go into any more detail in this course. If you want to know more, you could start with any of these pages: