O artigo aponta um problema básico de estudos que atribuem os maiores níveis de felicidade a países ricos: a confusão entre causalidade e correlação, o que é um problema porque muitos outros fatores influenciam a satisfação/felicidade com a vida — incluindo o que parece ser dos mais relevantes, o fator social. De lá:
To begin with, our findings point to the danger of putting too much importance on a correlation, such as the one found between money and happiness. Money is an easy predictor to quantify, so it’s understandable that it’s studied frequently, but many other factors affect life satisfaction. In fact, we also found highly significant correlations between satisfaction and imputed wealth in the small-scale societies we visited, but it was an extremely small effect compared with other features of the societies. And as shown by a finding called the Easterlin paradox, increases in a society’s wealth over time do not consistently lead to increases in life satisfaction across that society.