In this paper we argue that the use of mathematics in neoclassical economics, which constitutes the dominant position in economics, has become an «epistemological obstacle», in Bachelard's terms, preventing the development and openness of this discipline. The uncritical use of mathematical formalisation in neoclassical economic theory is criticised, which has contributed to distancing economic models from their basis in the real economy and has shaped a discipline centred on idealisations and abstractions. At the same time, by adopting absolutely just one theoretical approach – in this case neoclassical economics – this diversity of other economic theories and currents is neglected.