After a brief review of the main differences between New and Old Keynesian economics from the sixties this paper focuses on a tension between traditional sluggish measures of potential output commonly used by policymakers and the New Keynesian (NK) notion of this variable which conceptualizes it...

The original Keynesian paradigm differs from the Neoclassical Synthesis and even more so from the New-Keynesian approach. In this paper, a modern framework for the original Keynesian paradigm is presented. It will highlight the key elements of the paradigm. A model is developed to determine...