Q.Distinguish between positive checks and preventive checks in Malthus' theory of population.

Malthus argued population is brought back into balance with food supply by two very different kinds of checks.

In Malthus' 1798 theory of population, both positive checks and preventive checks act to bring a rapidly growing population back into balance with a more slowly growing food supply, but they operate through opposite sides of population change. Positive checks operate on the death rate — they are largely involuntary, harsh forces such as famine (when food genuinely runs short), epidemic disease (worsened by overcrowding and malnutrition), and war (often fought over scarce resources) — and they reduce population by increasing deaths. Preventive checks, by contrast, operate on the birth rate and are, in Malthus' view, more deliberate and 'moral' — chiefly late marriage and voluntary sexual restraint, which reduce the number of births before population pressure forces a positive check to occur. Malthus regarded preventive checks as the more humane route to balancing population and resources, though he doubted that enough people would practise the restraint required, which is why he expected positive checks to remain the more common mechanism in practice.