Morishima's Nonlinear Model of the Cycle: Simplifications and Generalizations

Michio Morishima's nonlinear model of the trade cycle (Morishima, 1958) is simplified and generalized to show, by means of the Andronov-Hopf bifurcation theorem, the existence of a periodic orbit. In addition, an attempt is made to place Morishima's contribution in the broader tradition of the work of the Japanese School of Nonlinear Trade Cycle Theorists and to place this, in turn, within the context and development of the tradition of mathematical economics in early post-war Japan.