Thomas Robert Malthus was a late 18th century political economist that went against the grain of population density theory that dominated the political economic thinking of his time. The widely held view was that “people were the strength of any country,” and that high population density promoted prosperity. Malthus challenged the virtue of populousness in his Essay on the Principle of Population (1798), which caused a lot of ripples. Malthus holds that populations grow geometrically, while our means of subsistence grow arithmetically. Thus, humans become more plentiful than the fruits of the earth and scarcity of subsistence factors leads to checks on population growth. As humans constantly push the limits of capacity, these checks will manifest themselves in conflict and war for one, and perhaps in human resolution such as family planning. This population-resource growth discrepancy and the resulting checks pertain to the carrying capacity of the Earth, or the frontier of production possibilities. He controversially states that charity is evil because it artificially eliminates the natural checks on population growth; he is thinking of the unborn generations that will be born into and most likely remain in poverty their whole lives. The biggest criticism of Malthus is that he has largely omitted technology from his theory. The assumption made by Malthusians is that arable land in finite; they forgot that we might be able to increase the fertility/productivity of land. He would respond that the preventative check still exists. Population has only been growing arithmetically because we have done a good job of deliberately limiting our rate of increase. The constraint still exists. Just because we haven’t reached the ultimate limit yet doesn’t mean it doesn’t exist. Malthus would surely point to increasing environmental degradation as generating the potential final limit to population growth.