h Malthus inspired the crux of Darwins theory, Darwin diverged from Malthus in a critical way. Darwins debt to Malthus lies in the borrowing of the concept of the struggle for existence. However, in general, what Malthus was concerned about was not how the struggle for existence affected the quality of the population (i.e., he did not suggest that in the struggle for existence the strong survive and the weak perish) but simply how it limited its numbers. Indeed, Malthus essay was written as a rebuttal to Godwin and Condorcet, both of whom had argued that humans, under conditions of equality, were capable of infinite progress and perfection. (Lewontin, 1974) In the essay, Malthus advanced the principle of population to refute that idea. Thus, Malthus principle argued that human society could never progress toward perfectibility because the population inevitably tends to increase beyond the means of subsistence and is kept within the bounds of its resources only by misery, vice, and moral restraint. Malthus principle of population was based on the supposed differences in reproduction rates between humans and animals and plants (who could only increase arithmetically, because they served mankind as a means of sustenance). (Vorzimmer, 1970)Darwin by contrast, shifted the center of attention from humans to the animal and plant kingdoms, because he was impressed by their enormous natural fertility, which was kept in check only by their own limited means of sustenance. By shifting his perspective from mankind to animals and plants. Darwin revealed the basic fallacy of Malthus argument. For if humans increased geometrically, animals and plants must also increase at the same rate, and perhaps even more, because overall their natural rate of reproduction is higher than that of mankind. Therefore, the struggle for existence, which to Malthus meant that hardship and misery were the defining features of human life, to Darwin meant that every species...
