Mankind will continue to reproduce until he consumes all available food supply, and then will only be prevented from expanding further by simple hunger.
Therefore: "The natural inequality of the two powers of population and of production in the earth, and that great law of our nature which must constantly keep their effects equal, form the great difficulty that to me appears insurmountable in the way to the perfectibility of society....
No one would go hungry, as resources would be allocated according to need, not according to wealth.
This course of reason would lead to the abolition of government, law, and private property (Lecture, 22 Jan 96), and a true democratic society would prevail.
Britain in the 18th century was a nation in transition.
The feudal system had been dying a slow death over the past several hundred years, and its aftereffects were visible everywhere, as tenant farmers, relics of the feudal era and a large percentage of the British population, were forced to leave their lands. The great landowners, seeing the profits to be made, declared many of the common lands to be private property, evicted the tenants, and began raising sheep.
Secondly, That the passion between the sexes is necessary and will remain nearly in its present state" (Essay... Assuming these two conditions, Malthus goes on to state the core of his argument within three short paragraphs: "Population, when unchecked, increases in a geometrical ratio.
Subsistence increases only in an arithmetical ratio.
His two initial postulates, that man must eat and will continue to reproduce, Malthus felt needed little defense.
Obviously, a person must eat in order to survive, and despite some speculation by the Utopian William Godwin that the sexual instinct may eventually diminish, Malthus saw little sign of this occurring at any point in the near future, and dismissed the possibility as mere conjecture.