Smiling builds trust
"A smile gains more friends than a long face." This Chinese saying has been scientifically validated by researchers of the Max Planck Institute for Evolutionary Biology in Plön and the Toulouse School of Economics in a study involving a behavioural experiment. The researchers examined whether subjects could induce trust with their smiles and profit from this. The results show that a smile rated as honest and genuine induces trust, and rightly so: on average, those individuals are also more cooperative. The study shows that genuine smiles are subconsciously produced more frequently when the stakes are higher and the smiler is "honest". It seems, then, that smiling this way is costly, and the associated effort is made only when worthwhile. Smiles rated as genuine are strong predictors of the trustworthiness of the individual in question.