Being single is bad for you, and expecting to remain single is bad for the people around you. Apart from the unpleasant feeling of being lonesome, it has health repercussions. Social isolation increases the mortality rate from cancer and cardiovascular disease, possibly because lonely people deal with stress less effectively. The pain of living alone increases the suicide rate.
You might therefore expect solitary people to be nicer to others in order to make friends, and to volunteer for charity to meet people. In fact, the opposite seems to be the case. Married people are more likely to give time to charity and even drive more considerately.
But this relationship could be caused by numerous factors. It might be that nice, caring people are more likely to find love and make a success of it. It could be that a third factor, such as religion, encourages people both to get married and to help others.
To find out whether the prospect of loneliness increased people’s care for others or diminished it, researchers conducted a devious series of experiments.
They told students that they had designed a questionnaire which could accurately predict how likely they were to be alone. The students sat the test, and were given feedback.
In fact, the psychologists couldn’t tell anything from the survey about how likely people were to find happiness with others, though the questions were the sort of things you might expect in such a test, asking whether the respondent was talkative, moody, outgoing, dominant or submissive.
Nevertheless, the researchers told some of the students that their answers showed they were likely to have a long and stable marriage and would probably always be around people who cared about them.
They told others that they were the type who would end up alone in life. Perhaps these students would have friends now, they might even marry once or possibly several times, but the relationships were likely to be short-lived, and as they aged they would be alone more and more.
After the test, the psychologists gave the students the chance to be caring. In one experiment, they said that they were collecting for charity and left the students alone with the box. Those who thought they would be loved in the future gave nearly four times as much.
In another, the students believed that they were about to do a second test, on creativity, but as the experimenter went to get the tests she knocked a cup of pencils on the floor. Two-thirds of those who believed that they would have close relationships in the future helped her pick them up, compared to only one in six of those who anticipated a future alone.
Dr Chris Paley is the author of Unthink, which has been published in six languages.
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