Overgeneralization – statements that are so general that they oversimplify reality.
 

Writers and speakers can exaggerate in a number of ways.  Statements that make sweeping generalizations tend to exaggerate and oversimplify reality, ignoring important details.  Generalizations are often useful in persuasion if they are worded carefully and if they are accompanied by clarifications and evidence.  Attempting to predict people’s behaviors leads us down the road to overgeneralization.  People often infuse stereotypes into logical reasoning, leading to overgeneralized conclusions.
 

EXAMPLE 1

A patriot pontificates: “In times of crisis, every American supports his President.”

This statement is an overgeneralization because it assumes too much to be proven possible.  Until most Americans can be contacted and surveyed, this statement cannot be proven valid.  We can correct this mistake by clarifying how many people profess to support the President, and under what conditions they would not.  Public support could change day by day and topic by topic.
 

CAUTION!  

Beware of statements that are too broad to be valid or contain “all or nothing” language.  Keep in mind also that an overgeneralization can occur in nearly every other logical fallacy, so don’t be lured into identifying every fallacy as an overgeneralization — you may be overgeneralizing yourself by selecting overusing this term on the logical fallacies test!

 
EXAMPLE 2

A little kid might say: “All birds can fly.”

Many young children make this overgeneralization when learning how to categorize the details of their world.  They have learned a general concept, but do not yet understand its exceptions.  A penguin, of course, is one of many examples of birds that cannot (or could not) fly.