Human Capital Theory proposes that formal education is necessary to increase a population s productivity: an educated population tends also to be a productive one and to present a higher level of social well-being that provides reduction of poverty and income inequality. Based on Human Capital Theory, Carlos Geraldo Langoni pioneered, in the 1970s, a study on the variation of income inequality in Brazil during the 1960s. His work demonstrated that education was the variable that best correlated with future income inequality. The inequality gaps involving children and adolescents in the Brazilian educational system were reproduced in wage gaps among workers in the labor market. Langoni contributed to the formation of a group of Brazilian researchers who were influenced by this theory. As of the 1990s, these researchers were involved in the public debate regarding the issuance of cash transfers conditional on school attendance programs. Although these conclusions based on Human Capital Theory presented by Langoni in 1973 were consistent and represented an important contribution to the understanding of income inequality, the political and academic environment of the 1970s ended by inhibiting the impact and recognition of the work. Starting in the 1990s, headed by his followers, those ideas and Human Capital Theory influenced governments, social policies, and somehow the choices of Brazilian society.