General propositions are normally supported by observing particular cases. But we often draw conclusions too quickly, on the basis of insufficient evidence. This fallacy, known as hasty generalization, can take many forms.
A single bad experience while traveling can prejudice our views of an entire city or country. Most of us have stereotypes about ethnic groups, professions, or people from different regions of the country, based on our exposure to a few individuals. Even a judgment about the character or personality of an individual is a generalization drawn from our observation of that person on specific occasions; here, too, we often jump to conclusions. And we can jump to conclusions about ourselves: we make a mistake, fail a test, have a problem in a relationship, and then draw a sweeping conclusion about our inadequacies.