On going inside to pay, there was another short queue. And that meant more time for things to come into my mind. But as I got closer to the front I became more aware of the guy behind the counter and the way he was dealing with the customers. He seemed to have a magic way of greeting everyone, of taking their cash or cards, and a genuine-looking smile on his face. Even the way he swiped the card through the machine had some type of art to it. I noticed that when the people in front of me had turned round to go back to their cars, many too had a smile on their faces and a spring in their step.

Last week I shopped at the supermarket on my way home from work. After an eternal wait at the check-out where I tried not to look as impatient as I felt, my shopping was beeped past the scanner by a wonderfully cheerful, friendly and erudite woman. I don’t remember what we spoke about, but the minute in her company left me feeling better than I had been beforehand! As I left I thought that this woman probably transmitted more “good vibes” to the people she came into contact with than most of the doctors I’ve seen in my life put together!

Ana & Raúl weren’t simply charging people for the goods they bought – they were, in effect, giving our “good mood” tanks a free top up too!

How does this “mood infection” take place?

The concept of “emotional intelligence” was brought to the western masses with the publication of a book of the same name in 1995, by U.S. psychologist Daniel Goleman. Long before then, the Swiss psychoanalyst Carl Jung, born in 1875, reported that “emotions are contagious”. Other schools of thought have been aware of this for centuries. Research over the last 25 years has shown that some people have a natural ability to transmit emotions (which then affect mood) while others are more susceptible to “contagion”.

“Emotional contagion happens within milliseconds, so quick you can’t control it, and so subtly that you’re not really aware it’s going on,” said Dr. Elaine Hatfield, a psychologist at the University of Hawaii, and leading expert on the subject. The more emotionally expressive people are, the more likely it is that they transmit their moods to someone they talk with.

One study had two people sitting facing each other, without talking, waiting for an experimenter to return to the room. The pair consisted of one person who was highly expressive of emotions, the other less expressive. Two minutes later, when the experimenter came back and asked them to complete a series of questions about their moods, the mood of the more expressive of the pair had taken over the other person, presumably through body language.

Swedish researchers found in 1986 that when people viewed pictures of smiling or angry faces, their facial muscles changed slightly to mimic those faces. While the changes were rapid & invisible to the eye, using electrodes to trace electrical activity in the muscles, it was shown that seeing the faces evoked the moods.

How important is all this in everyday life?

You could argue that moods & emotions come and go and that we have no control over them. In “Emotional Intelligence”, Goleman argues against this, saying that skills can be learned and developed to help better manage one’s inner emotional life and, through this, the way we interact with others. Research suggests that not only do our moods affect how we see our future, but that they also influence our judgments by making either positive or negative memories more readily available. Leaders in the field point out that people are largely unaware that a good or bad mood is creating an optimistic or pessimistic outlook: it simply seems that the facts support one or another view. In other words, moods “colour the glasses through which we view the world” and prevent us from taking a more rational or objective view.

Finally…I’d like to pay a tribute. To all the people out there whose good moods are contagious…whether they know it or not.