Acts of kindness are proven to increase altruism in others.
Research has shown that that acts of kindness might stimulate others to initiate similar behaviour. In a study conducted by Schnall and colleagues in 2010, it's explained that 'feelings of elevation, elicited by witnessing another person perform a good deed, have been hypothesised to motivate a desire to help others'. In one experiment, people were far more likely to volunteer for a subsequent unpaid study if they witnessed helping behaviour performed by others.
In second experiment, it was shown that people who witnessed virtuous acts performed by others spent twice as long assisting the experimenter with a tedious task than other participants in a neutral emotional state. This phenomenon was demonstrated in those who witnessed virtuous acts, but not in those simply experiencing feelings of amusement or happiness.
The findings of this study provide proof that witnessing acts of kindness may evoke in us positive emotions that, in turn, are more likely to lead to tangible increases in similar altruistic acts.
Source:
1. Schnall S, Roper J, Fessler D. Elevation Leads to Altruistic Behavior. Psychological Science [Internet]. 2010;21(3):315-320. Available from: https://journals.sagepub.com/