Throughout his writings, especially in the six editions of his Essay on Population, Malthus’ extended discussion of his population principle – the fundamental tendency towards divergence between population and subsistence growth rates – suggests several solutions to the problem he defined. To clarify the nature of his theory, detailed conceptual analysis is essential. The four human roles of worker, utilitarian, procreator and consumer identified by Malthus need to be assessed to explain the behaviour of the human population. Subsistence, like human behaviour, is a complex idea. It takes different forms, ranging from basic food to luxuries, and is rendered obscure in Malthus through his use of many different expressions for it. The concept of subsistence is analysed in this article within the eighteenth century framework of the four stages of economic growth and largely uses a population model for a single country rather than for the whole world. The conclusion to this enquiry is that although Malthus admits that an advanced country is able to deal with population growth through industrial specialization and food importing, he rejects this solution in favour of an approach based on a balanced economy.