Malthus in his book ‘An Essay on the Principle of Population’ observed that the danger of population growth precluded progress towards a Utopian society. He said that “the power of population is indefinitely greater than the power in the Earth to produce subsistence for man”.
He also brings support to his theory in the law of diminishing returns, the implication of which is that food production is bound to lag behind population growth. So, his views regarding population is pessimistic.