The terms of Malthus’ population principle are clear: there is an intrinsic divergence between population growth and the subsistence needed to sustain it. But difficulties arise when we look at the solutions proposed by Malthus in his writings, since certain essential concepts are used in complex ways. In this article, Donald Rutherford contributes to the debate by analysing the different concepts of human behaviour and of subsistence that appear throughout Malthus’ works. He examines in turn the various solutions to the population problem envisaged by Malthus, and finds each one wanting, before concluding that Malthus appears to advocate a diversified and balanced economy. But Malthus is wary of overspecialization in industry and commerce, and argues for equilibrium between the different sectors and different economic activities, thereby rejecting the solution that was to prevail in the following centuries.