Since transactions of goods and services take place in currency, economic factors have a heavy weight in influencing social dynamics. In a famous quip, Groucho Marx observed that “in life there are many things more important than money, but to buy them you need to have bucks”. Said in a more sober way, the level of income is “a fundamental means to important ends” (Anand and Sen 2000, p. 100). However, each person’s identity is an archipelago composed of many selves. In his great poetic composition Leaves of Grass, the American poet Walt Whitman, with the famous line “I am large, I contain multitudes”, wanted to translate his existential journey into verse. He considered the contradictions and complementarities that accompany the individual’s participation, through income, in a plurality of life spaces. It is certainly no coincidence that Whitman placed the construction of the individual’s identity in a relationship of continuity with nature and with the feeling of life that unites all men. The “multiple self” (Elster 1985) is the reflection of the social interaction in which the individual constructs his own well-being. On the one hand, income is the pre-condition for mobility; on the other hand, it is the socio-economic factors at work in society that diversify the opportunities for social mobility among people.