"Over-breeding" has likely been in place from the start. What kept increasing population in check was high infant mortality rates and generally a lack of resources, and during the current period either enforced policies (like that of China) or greater prosperity (as seen in industrialized countries with lower birth rates but far higher resource consumption levels per capita).
As I pointed out before, the population increased thanks to the use of oil and other technologies, which in turn also led to increased resource consumption per capita. The latter led to lower infant mortality rates, which in turn contributed to increased population.
There was no "general philosophy of over-compassion and over-tolerance," for as one study reveals, the percentage of deaths due to war compared to world population during the previous two centuries was higher than previous centuries:
http://democraticpeace.wordpress.com/20 ... st-of-all/Population increased likely because the technology to kill was outweighed by the technology to prolong life. And it did not help that a global capitalist system which stemmed from the same use of various technologies ultimately required increasing numbers of people consuming more in return for more profits.
Thus, in many ways people from the past "understood" the limits of resource availability. It is just that they didn't have the means to keep population low, so they let nature do such. That is why life expectancy rates remained low and steady for several centuries. That is why global population barely increased until various technologies were employed.
As explained above, the two current means to control population involve forced policies, like that of China, and increasing prosperity, resulting in lower birth rates in various industrialized countries. However, the one-child policy in China has backfired, leading to increasing numbers of boys, and now, increasing resource consumption per capita. Worse, the lower birth rate phenomenon in industrialized countries has led to increased resource consumption which has offset any savings due to lower birth rates. On top of that, population ageing has taken place in some, prompting communities to encourage immigration or raising families.
Who has been promoting population control worldwide? Usually, philanthropists and powerful multinational corporations, especially those involved in pharma businesses. Ironically, several of them say nothing about overconsumption in rich countries, preferring to blame "Third Worlders" for resource availability issues. Another irony is that their main motive for controlling population in poor countries is not to decrease resource consumption but the opposite, as population control is supposed to lead to more stable economies, and with that, more prosperity which translates to more spending, and thus more sales for corporations.