All people need to evaluate their opinions and abilities.
When no objective means are available they do it by comparing their reactions with reactions of
other people.
The more ambiguous the situation is and the more uncertain people are. the stronger is their need
for social comparison.
According to Festinger we compare ourselves with people who are similar to us.
We turn to others who are similar to us so that their reactions will provide an accurate basis for
our own judgements.
How does this process of social comparison work?
When a person begins comparing his reactions with reactions of other people he attempts to
reduce any discrepancies between him and the others.
Each person uses reactions of other people as his source of knowledge what is correct.
And if he finds that these reactions are very different it is upsetting to him.
That is why there are strong pressures towards uniformity of reaction in a group.