EN
Keynesian thought influenced not only the neoclassical economists who fully embraced his theories and developed them in their research, but also became an important reference point for those scholars who remained in opposition to mainstream economic schools. This paper discusses the impact of J. M. Keynes' work, and the schools inspired by his theories, on the mainstream economics. The present study focuses on the conditions that contributed to the approval of J. M. Keynes' views by both mainstream economics, dominated by classical and neoclassical concepts, as well as by various post-Keynesian schools. The latter, in fact, relied to a greater extent on the scientific achievement of M. Kalecki, whose theories are often considered to be very close to those of Keynes.