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People generalize when they take one aspect as representative of the whole leaving no room for exceptions. Generalization can be harmful when it results from persistently clinging to a wrong conclusion drawn from a single event without making allowance for flexibility. Generalization is only helpful when it enables us to cope with new situations from what we have gathered from past experiences, as not all generalizations are based on erroneous information or unsound reasoning. There are valid generalizations as well.We form our beliefs from generalizations and these beliefs could be negative or positive. Either way, they have a long-term effect on our life. If we, say, encounter a bad behaviour from a member of a particular racial group, we hastily brand such behaviour as typical of that group. This is how we filter our experiences using our mostly biased beliefs. We then delete information that does not support our beliefs and distort information to reinforce the beliefs.
We often make decisions based on generalizations. We are not concerned whether the decisions are justifiable or not. For instance, if a woman has been unreasonably jilted by a man, she will exercise utmost caution when she finds herself acquainted with another man. It is very likely that she develops any kind of trust in him, let alone build up a relationship with him. Her sweeping generalization that all men are alike can very well be detrimental to her well being. Most generalizations are formed out of bad experiences and usually have an unfavourable lasting effect.
Generalizations at times are necessary for self-preservation. If a spider has given you a real scare, you would from then on steer clear of all spiders of any size, colours or shape, or at worst may develop arachnophobia. A lay person, not knowing much about snakes, regards all snakes as poisonous. If you have once been growled at or bitten by a dog, would you go near an even seemingly tame one?
Generalizations are often used in one’s language. Generalized statements invariably include words such as ‘always’, ‘all’, ‘everyone’, ‘nobody’, ‘never’. For example, “Nobody cares about me.” implies not even one person cares about him/her. This could have been due to one or two persons not caring for him/her but instead being generalized to include everybody. It requires a response like: “Has there never been one person who cared about you?” “Who really does not care about you?”
It is human nature to generalize. However, if we can constantly bear in mind that there are exceptions to the rule, we can then modify our beliefs which basically are generalizations.