His name is Thomas Malthus. He was a minister in the Church of England who wrote and published prolifically on the subject of population a little more than 200 years ago.

He gave his name to a term that prevails to this day: Malthusian, which has come to mean calamitous.

Malthus argued that since the planet's resources are finite, but that the population's capacity for growth is exponential (can increase at an increasing rate), there must be natural corrections known as Malthusian catastrophes.

Initially, Malthus favoured the Four Horsemen of the Apocalypse -- war, pestilence, famine and disease -- as agents of demographic correction, although in later publications the good minister enthusiastically advocated sexual abstinence as a way of keeping population growth in hand.

Malthus's thinking was bold because it ran counter to the prevailing orthodoxy: that there were more or less no limits to growth and to the potential improvement of man and society.

Malthus was writing at a time when great land discoveries and settlement programs in the New World were under way.

For those predisposed to biblical metaphors, and who isn't, there is plenty to choose from in this debate.

For Population Growthists there is God's very own advice to "be fruitful and multiply".

For the disciples of Malthus, there is "repent now and abstain to avert eternal damnation later", or words to the effect.

Malthus's thinking kicked around in subsequent decades and centuries.

Indeed, some argue that Malthus influenced the work of the evolutionist Charles Darwin, who published his theories in the middle of the 19th century.

But in demographic terms, it wasn't until the late 20th century that Malthus's thinking got another airing. Not that it was recognised as Malthusian logic at the time; it was given a makeover by the US academic Paul Ehrlich, who published The Population Bomb in 1968.

Ehrlich was an entomologist who had studied the rise and fall of insect colonies; his leap across to human populations followed a similar logic.

The human population (then at four billion) was too high and this would lead in the 1970s to famine, disease and social unrest.

Not quite the Four Horsemen of the Apocalypse, but close enough to qualify as a Malthusian resurrection.

It is fair to say that Ehrlich was, and remains, the darling of the anti-growth movement in the US and beyond.

However, his reputation took a battering in the early 80s when Julian Simon, an English academic working in the US, challenged the Malthus-Ehrlich idea that resource depletion limits population growth.

In his book The Ultimate Resource (1981), Simon argued that as a resource diminishes, the price rises, prompting exploration and recovery of additional reserves or substitutes, which ultimately reduce the cost of the resource.

Ehrlich, of course, rejected Simon's thesis and dismissed him as a fringe player.

This led to a famous wager. Simon bet Ehrlich ($US1000) that the price of a basket of five scarce commodities would ultimately fall during the 80s; Ehrlich bet the price would rise because of scarcity. Ehrlich chose the basket: copper, chromium, nickel, tin and tungsten. The price of the basket of scarce commodities fell by 57 per cent over the decade to October 1990. Ehrlich conceded and paid up.

Simon's book was reportedly an influence on the Danish academic Bjorn Lomborg who, like Malthus, challenged the prevailing orthodoxy with regard to population and resources. But instead of challenging the growthists, Lomborg, like Simon, challenged the Malthusianist's view of the world.

Lomborg published The Skeptical Environmentalist in 2001 and in which , through the bold use of evidence and data, he credibly refuted many of the claims of imminent environmental calamity, indeed of the Malthusian catastrophe.

In the same vein as Lomborg is British journalist and author Matt Ridley who published The Rational Optimist in 2010, which argues that when viewed from the altitude of the broad sweep of history, the quality of life for more and more people is improving as the world population increases.

The most powerful point that I think Ridley makes is that the population is stabilising naturally without the interventions imagined by Malthus, or Ehrlich for that matter. Ridley cites the birth rate in Bangladesh as evidence: down from 6.8 per woman in 1955 to 2.7 today.

As the standard of living improves, as education rates rise, as the spread of Western values, culture and attitudes to women pervade the mostly non-Muslim world, the rate of population growth subsides.

That is Ridley's contribution and in many ways it was also Simon's point.

The question that so perplexed and so motivated Simon, Lomborg and Ridley is the same. Why is it that when predictions of Malthusian catastrophe fail to materialise, there isn't a fundamental reconsideration of the proposition?

Ehrlich's lost wager did not cultivate a different point of view; it proved nothing.

Indeed it could be argued that the current green orthodoxy of an impending global calamity -- of biblical proportions -- that will befall us all if corrective action is not immediately implemented is an extension of Ehrlich's 1968 thesis: that the world cannot sustain current, let alone future, populations. And yet the battle rages on vehemently.