Abstract
Trust is key for economic and social development. But why do we trust others? We study the motives behind trust in strangers using an experimental trust game played by 7236 participants, in six samples representative of the general populations of Germany, Italy, Japan, Luxembourg, the UK and the USA. We examine the broadest range of potential determinants of trustor sending to date, including risk tolerance, preferences for redistribution, and conformity. We find that even though self-interest, indicated by expected returns, is relevant for trustor behaviour, the most important correlate of sending is participants' altruism or fairness concerns, as measured by giving in a dictator game. We also find that in our large and representative sample, behaviour in the trust game and responses in a trust survey are significantly correlated, and that similar correlates-altruism in particular-are relevant for both.