In order for a society to survive, the poor must execute preventative population checks so that the food supply will be sustained. These preventative population checks are ways that man control the population to a point at which food supply is sufficient enough for a society to be able to function properly. These preventative population checks consist of abstinence or limiting the amount of children per family. This method of controlling the population is necessary because food supply is a linear growth while population growth is exponential, therefore the population must be controlled enough so that there is enough food. Also, another reason that Malthus argues that checks are necessary is because without them the poor will continue to grow in size due to their low incomes and high costs to support a large family. With these checks on the poor, Malthus believes this will solve the problem of ever having an insufficient amount of food or resources to support the society.