This article attempts to show that the relationships between theory and practice as far as evaluation is concerned constitutes, in fact, an aporia which opposes and connects at the same time the «technician system», devoided of meaning (Ellul, 2012), and the continuous research for a theory generating meaning. In support of this aporia, one relies, in particular, on a number of papers, some of which are recent, collected by Mottier Lopez and Figari (2012), and take an epistemological stock of research related to evaluation in education. First of all, one recalls the criticism of the «technician evaluations», questioned by researchers because of a lack of theorisation. One then takes stock of the progress made regarding the «theoretical thinking» built up around evaluation, by questioning the writings of authors who, because they are unable to propose a «general theory», construct «theorisations». To that end, in the papers analysed, the elements constituting an emerging evaluation theorisation have been classified in three constituent elements: 1- a crossroads of social sciences and humanities disciplines with a view to explaining, from their respective viewpoints, the phenomena related to evaluation; 2- a methodology for the rapidly evolving measurement, moving towards a greater integration of the theoretical frameworks for its development; 3- the emergence of a configuration of increasingly restricted and unifying evaluation paradigms. Even if one fails to solve the initial aporia, one thus gets a glimpse: a pretheory of the evaluation in the making.