PRINCIPLE OF POPULATION

12000 years ago, the introduction of sedentary agriculture ensured food was plentiful. The consequence was the growth of population (now there are over seven billion human beings).

The 18^th Century English Economist Thomas Robert Malthus believed food fundamentally constrains population growth. In his Essay on the Principle of Population, he argued that the planet’s population would always persist at a level simply adequate to support life; nothing more, nothing less: the subsistent level. He also argued that food in abundance or short supply has a levelling effect. He didn’t agree with the idea that more food means more births and longer lives, consequently population’s growth. This is because population doesn’t increase in the same way food does. Food doesn’t multiply exponentially. As consequence, food supply can no longer meet the demand of everyone, so the population increase is short-lived. People dies of hunger and equilibrium returns.

Land availability is outside human control (just like famine and disease). Malthus has called them positive checks. They nudge and cajole population back towards subsistence. Malthus acknowledge these positive checks in critiquing the Elizabethan “Poor Laws”. He believed that social welfare and food redistribution to the poor would unravel in the long run.

According to Malthus, it was possible to outwit the population ‘trap’ with preventative checks, human preventative behaviour or moral restraint to beat the system (for example celibacy, delayed marriage, emigration).

His theory on population has been acknowledged as the most influential work of its era.