Abstract: While the various streams of environmentalism agree in claiming that the current patterns of economic activity are unsustainable for natural resources, they disagree in answering the following question: who is the responsible? Two different answers have been provided: the people or the socio-economic system. The first answer claims that people are inter-temporally greedy. Unsustainable economic patterns simply reflect the little importance that current generations attribute to the living standard of future generations. According to the second answer instead, people would prefer a more sustainable path of the economy but some failure of the socio-economic system prevent this outcome. We provide a test of the basic hypothesis on which these two views diverge: the degree of people’s concern for the conditions of life of future generations. We derive this information by estimating the relationship between people’s current subjective well-being and their expectations about the living standard of future generations, i.e. a future far enough to concern only future generations. Our findings support the second environmentalist view.