In a previous paper, Growiec (2007) showed that conventional growth models do not satisfactorily explain exponential/geometric growth. A balanced growth path with strictly positive rates requires “knife-edge conditions,” Growiec says. This is because balanced growth paths are fragile and sensitive to the smallest disturbances in parameter values. Growiec’s latest paper, which deals with the “knife-edge” conditions of balanced growth, looks at this theoretical approach in the context of other growth models found in literature on the subject. The author’s approach sheds new light on the ongoing debate on the sources of economic growth.