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When reading about human capital theory, literature is extremely abundant. It is widely recognised that the theory of human capital, in the strict sense, spread out around 1960, resulting in that branch of economics known as the economics of education. In the same way, it is undeniable that the theory of human capital is deeply rooted in at least two centuries before, starting with Adam Smith’s work. The debate on the concept of human capital covering the time span that from Smith reaches the well known Jacob Mincer’s doctoral thesis has been particularly intense over the Sixties when indeed human capital became a concept integrated within the economic science. The outcome of this debate has been a pluralism of perspectives, sometimes even in conflict with each other. 
According to its classical formalisation, we can define human capital as a set of skills and characteristics that increase a worker’s productivity and that have sources in e.g. innate ability, schooling and training. This definition only captures some of the concepts related to education and training; some other concepts, in particular, a multidimensional approach that we can find already in Smith’s thought, have lost consideration and retrieved only with the formalisation of another theory: the human capability developed by Amartya Sen.
Even though these aspects have been rediscovered, the empirical analyses populating research in the field of education still rely on the key concepts of the theory of human capital: education can be assimilated to an investment, whose rate of return can be compared with other types of investment. The rate of returns to education is usually computed on the basis of the returns estimated through the Mincerian wage equation, which is based on the assumption that schooling decisions will maximise the net present discounted value of the individual. 
This work provides a historical review on the role of education, from the point of view of some major economists, from Adam Smith to Amartya Sen, touching Mill, Marshall and the founding fathers of the Economics of Education: Schultz, Mincer and Becker. The aim is to highlight that a multidimensional approach to education was present even in the first contributions on the topic; yet, precious concepts on education have been left behind in the process of formalisation of a unitary theory such as the human capital theory and, as a consequence, they do not find a corresponding application in empirical research.