In this keynote speech, Roger Backhouse gives a historical overview of theories on secular stagnation: how it evolved from a description of the economic situation, especially in the U.S. of the 1930s to an analytical tool and then lost importance until its current revival. Backhouse touches upon the contributions of J. A. Hobson, Alvin Hansen, Evsey Domar and Paul Samuelson. 2015 Level: advanced Theories of stagnation in historical perspective Roger Backhouse IMK Eckhard Hein criticises the mainstream's view of secular stagnation as the result of a negative real equilibrium interest rate. Arguing in a Keynesian spirit with particular reference to Steindl, secular stagnation is considered to be a result of shift in the functional income distribution, and oligopolistic organisation of industries, leading to excess capacity and reluctance to invest. This acts as a drag on effective demand and results in secular stagnation. Distributional policies and public investment can, however, overcome stagnation its tendencies. 2015 Level: advanced Secular Stagnation or stagnation policy? Steindl after Summers Eckhard Hein IMK This lecture acts as an introduction to the Macroeconomics course (ECON 720) at John Jay College. Throughout the lecture, the classical and Keynesian conceptions of macroeconomic relationships are contrasted. 2021 Level: beginner Macroeconomics with J.W. Mason, Lecture 0: Introduction J.W. Mason The Economics Department of John Jay College of the City University of New York (CUNY)