As emphasised by various authors, research and reflections on the topic of trust show that the base of well-being and subjective perception of it is strongly associated with the level of trust that exists in each society. This perception of well-being is an important factor that promotes or blocks the development of trust in a society.
Moreover, several studies indicate a strong association between interpersonal trust (defined as where most people are believed to be trustworthy), health, wealth, and subjective well-being. The sense that one lives in an environment where people are trustworthy seems to generate significant effects on the perception of the general well-being of the respondents themselves.
In addition, comparing data from different surveys, some authors have showed that "feeling that others can be trusted," be it with whom one lives with or works, or even with authority figures, is associated with high subjective perceptions of personal well-being. They also concluded that the government's ability to ensure a trustworthy social environment, and to provide efficient and honest services to citizens, is extremely important for general life satisfaction.
Other authors have shown that trust is related to economic and income inequality in societies. In countries with large income inequalities, it is more difficult to develop and maintain links between those at the top and those at the bottom of the income scale. In these scenarios, it is difficult to create bridges across social groups because it is unlikely that individuals across different social strata will share a sense of purpose or common goals and, therefore, trust one another. In fact, several researchers have shown the relationship between trust and income and economic inequality as one of the best "predictors" of the level of interpersonal trust in a society.
Further research, using various statistical techniques, suggests that it is inequality that affects the level of trust and not vice-versa, that trust impacts the level of inequality. This is important because it establishes the direction of causality. Moreover, this indicates that what is responsible for increasing the level of trust in a country is not so much the economic level of well-being per se, but rather the level of economic equality perceived among the individuals in that same country.
Seen another way, we can say that similarity is the first step to trust because it promotes attraction and, subsequently, emotional comfort. One example of how we can see similarity playing an important role in trust is in Scandinavian societies. Here we can see both a high score on interpersonal trust surveys and, from a historical, evolutionary, and comparative point of view, these groups are, generally, all quite similar.
Therefore, if we want to build societies where people trust more, we also must produce more equal societies.
 Fukuyama, 1996; Roth, 2006; Helliwell, 2008; Huang, 2008
 Helliwell, 2008
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 Uslaner, 2002, 2006
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 Bartolini, 2003; Uslaner, 2005; Rothstein, 2005; Wilkinson, 2008;
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