The paper highlights that economics of education formally evolved in the last century, but its conceptualization was articulated centuries ago. The most prominent economists to address issues of human capital were A. Smith, J. S. Mill and A. Marshall. The residual portion of economic growth which was unexplained by traditional economic inputs was, instead, one main reason of the spreading of the literature on education after 1960. In those years, the Chicago School and G. Becker adopted the rates of return approach on human capital investments as fundamental base of research. The methodology was not full-accepted and a large part of the early criticism is present, now, in the human capability approach of A. Sen.