The neolithic agricultural revolution massively increased the quantity of food which could be produced from a given area of land and thereby made possible a matching growth in population. Whereas previously men and women had competed with other animals to secure a share of the natural products of the land, the development of agriculture, which was the defining feature of the change, meant that plant growth over vast areas was restricted to plants for human sustenance or to feed flocks of domesticated animals. This multiplied by orders of magnitude the capacity of each acre suitable for agriculture to support a human population.

All economies which developed in the wake of the neolithic food revolution may be termed organic. In organic economies not only was the land the source of food, it was also the source directly or indirectly of all the material products of use to man. All industrial production depended upon vegetable or animal raw materials. This is self-evidently true of industries such as woollen textile production or shoemaking but is also true of iron smelting or pottery manufacture, although their raw materials were mineral, since production was only possible by making use of a source of heat and this came from burning wood or charcoal. Thus the production horizon for all organic economies was set by the annual cycle of plant growth. This set physical and biological limits to the possible scale of production.