07/02/2013 12:52 GMT | Updated 09/04/2013 06:12 BST

Paying It Forward: The Psychology of Random Good Deeds

My Facebook pal, Debbie, in America was at a drive-thru Starbucks the other day. Nothing unusual in that, but this time, when she put her order in, she was informed that the car in front of her had paid her bill. The car in front had 'paid it forward' - a concept that refers to the random acts of kindness whereby people do something nice for someone else in the hope that this good deed will be 'paid forward' and inspire the lucky recipient to carry out their own random acts of kindness to others.

Paying it forward is not a concept that has gathered huge momentum in the UK, but apparently is quite a big thing on the other side of the Pond. I think if some random stranger paid for my coffee here in Manchester, my reaction would be more suspicious than grateful; we in the UK, are simply not used to strangers performing arbitrary acts of kindness for us. Strangers in this country are not renowned for letting us cut in front of them when trying to make a right turn in rush hour, or stopping to let us cross the road (I once counted 34 cars pass me and my kids by before one kind soul slowed to let us cross)... buying us coffee? Not a chance!

But, imagine, if the Pay it Forward campaign caught on here. Imagine if we did buy people we don't even know, drinks, or complimented random strangers on the train on their clothes, or left encouraging post-it notes in library books, or put change in expired parking meters? Would it make our world a nicer place? Could we really spread happiness; would our random act of kindness really inspire others to 'pay it forward'?

According to a study by Stanford University psychologist Sonja Lyubomirsky in 2005, students who carried out five random acts of kindness a week, reported higher levels of happiness than a control group. That I can understand; we feel good when we do good because we feel that we have made a positive contribution to society and we experience what psychologist call 'moral elevation'. But, can these good deeds really spread, and inspire recipients to perform their own acts of kindness?

Well, yes, apparently they can. According to a study published in the Journal of Personality and Social Psychology recently, even reading about acts of kindness can evoke this moral elevation, never mind being the actual recipient of these acts. And people who have moral elevation are more likely to perform good deeds themselves. This is because if we feel we are 'good', we do 'good' things in order to reinforce this view of our self.

Thus, if someone lets me out into the traffic during rush-hour, I am more likely to let the next car in. If someone does something nice for me, I am likely to do something nice for someone else. It's basic psychology. It also ensures that we obey the 'law of reciprocity', which is a very powerful psychological pull we experience when someone gives us something or does something for us; we yearn to return the favour somehow (which is why charities often send us free gifts like pens or stickers - they hope we will be unable to resist the yen to reciprocate their kindness).

So, what are we all waiting for? We have the power to make the world a better place by one random act of kindness. The next time you are in the coffee shop picking up your latte on the way to work, why not pick up the tab for the customer behind you; you never know what it could lead to.