Kindness is contagious, scientists have discovered. And good acts by a handful of individuals really can make a difference.
Professor James Fowler, of the University of California, and his colleagues have found that when a person receives a gift or favour they are more likely to be generous and give an even bigger gift to another person.
The second person then does the same thing and a wave of generosity spills through social networks and into the wider world to people that the original gift giver has never met.
In all, one good act seems to be the catalyst for three others.
"Co-operative behaviour is contagious and it spreads from person to person to person," the Telegraph quoted Fowler as saying.
"When people benefit from kindness they "pay it forward" by helping others who were not originally involved, and this creates a cascade of co-operation that influences dozens more in a social network," he added.
For the study, researchers at the University of California along with scientists at Harvard University recruited participants to play a public goods game where they had try to build an economy and they could give money away to other players or keep it for themselves.
The researchers found when one person gave money away, the person who received it was more likely to give away an even greater amount to a fellow participant.
"When one person gives money to help others in a public-goods game, where people have the opportunity to co-operate with each other, the recipients are more likely to give their own money away to other people in future games," Fowler said.
"This creates a domino effect in which one person's generosity spreads first to three people and then to the nine people that those three people interact with in the future, and then to still other individuals in subsequent waves of the experiment.
"You don't go back to being your old selfish self. As a result, the money a person gives in the first round of the experiment is ultimately tripled by others who are subsequently directly or indirectly influenced to give more," he added.
However, Fowler cautioned that bad attitudes spread just as easily as goodwill in the games.
"The contagious effect in the study was symmetric; uncooperative behaviour also spread, but there was nothing to suggest that it spread any more or any less robustly than co-operative behaviour," he said.
The study has been published in the Proceedings of the National Academy of Sciences. (ANI)