more stable the evaluations of social mobility afforded by the status indicators.On the other hand, the less sound and stable the social conventions and technological advances, the less representative the assessments will be. In such cases, conflicting or unconvincing results may have been influenced by changes in social conventions and/or technological advances, rather than changes in merit and/or performance of individuals in the labor market.These changes in social conventions and technological advances most closely affect education and occupations[12]. The importance of each will depend on the prestige they enjoy in society at a given moment in time. For example, IT has risen in social status since it joined the list of fields of knowledge and still allows many workers without a college education to earn good wages in the market. Another example is how workplace automation decreased the real or relative value of the wages of bank staff, especially tellers, in relation to what they earned before and to other occupations.There is another emblematic example we were told by a trade unionist from Belo Horizonte in the mid-1980s, when we were doing a field survey on electronic automation in the Brazilian automotive industry[13]. In a steel plant in Minas Gerais conventional machining was replaced, thus laying off a mechanical turner, who until then performed the task with a traditional machine tool. The company was modernized and purchased a computerized numerical control machine tool (CNCMT).The mechanical turner then went on to show the movements he performed in the machining of parts so that the programmer could prepare the program to be installed in the CNCMT. After several work meetings between the two, the programmer felt ready to install the program and get the CNCMT to operate. The mechanical turner, however, warned that if this were done there was a serious risk of the experiment aborting and, worse, breaking the machine. The mechanical turner believed that the program had not captured his machining movements well enough. But the programmer insisted on putting the machine to work. Result: it broke.The latter example illustrates at least two important and interdependent aspects. First, the tacit knowledge of the machine turner, even if not systematic, is critical not only for him to do his job well, but also to see and understand other knowledge fields, though he has no education to do so. Second, the programmers formal knowledge is not enough to do his job, even if he interacts with another worker on a specific task. He lacks the practical work experience, the tacit knowledge.This observation applies to any type of occupation and specialty. The question remains: how far can experience-based knowledge go and how far can formal education go? Should not the two be developed at the same time? And evaluated in terms of performance and remuneration in a more compatible way?Thus, with these three examples, and changes in social conventions and technological advances occurring in the market and in society all the time, pure and simple comparison of social status may be insufficient and even misleading, reflecting more or less the social achievement of individuals from