Malthus and Darwin: world views apart.
Predictions that the rate of growth of the human population will catapult humankind into an ecological crisis were made as early as the second century AD, when the theologian Tertullian warned that "The final evidence of the fecundity of mankind is that we have grown burdensome to the world: the elements scarcely suffice for our support, our needs grow more acute, our complaints more universal, since nature no longer provides us sustenance. In truth, pestilence and famine and wars and earthquakes must be looked upon as a remedy for nations, a means of pruning the overgrowth of the human race." (Quoted from Lovejoy 1948, pp. 321-322).
Malthus was to repeat this warning some 1600 yr later in the Essay on the Principle of Population, first published in 1798. The Essay provides an outline of, and background to socioeconomic arguments that were to help shape economic and social policy in Britain throughout much of the 19th century. It contains two arguments that were to play a central role in Darwinian evolutionary theory: a species produces more individuals than can be sustained; this results in a struggle for existence. Such similarities between Malthusianism and Darwinism, together with Darwin's (1859, p. 117) description of the struggle for existence in nature as ". . . the doctrine of Malthus applied with manifold force to the whole animal and vegetable kingdoms: . . ." have given rise to claims that Darwinism is a reflection of Malthusianism. For example, Lewontin (1993, p. 10) claims that "What Darwin did was take early-nineteenth-century political economy and expand it to include all of natural economy." Similarly, Desmond and Moore (1991, pp. 275-276, 413-414) describe how "Darwin's new way of viewing nature . . . . kept faith with the competitive, capitalist, Malthusian dynamics of a poor-law society," that his theory ". . . made Nature an ally of the middle-classes." And Ho (1983, p. 15) contends that what Darwin offered was ". . . an imagery of reality, gleaned from the perspective of the ruling classes, |which| was projected back, via a scientific theory onto reality itself. . ." There is little doubt that Darwin gained important insights from Malthus, most notably, that populations typically produce more individuals than can be supported (Desmond and Moore 1991, p. 264). But it will be argued that this does not justify the description of Darwin's evolutionism as somehow an expansion or projection of Malthusianism. Such descriptors imply that the fundamental assumptions underlying Malthusianism are recognizable within Darwinism, that Darwin incorporated not only Malthusian arguments but key elements of the Malthusian worldview. That this is not the case will be demonstrated both by projecting Malthusian arguments onto nature and by examining the assumptions that underlie these arguments.
Malthus (1798) argued that, in the absence of reproductive restraint, a population would increase in size at a rate faster than that of the resources needed to maintain it. He urged that the well-being of humankind could best be safeguarded by individuals desisting from reproduction if they were not able to sustain the resulting offspring without assistance. This would ensure that supply met demand. Anything that opposed this principle, especially the Poor Laws (which imposed taxes and rates for the support of the destitute), had to be resisted. Malthus argued that resistance was necessary because assistance had repercussions other than a redistribution of resources from resource-rich to resource-poor segments of society. In particular, the availability of assistance would persuade the poor to produce more children than they would otherwise produce, but it would not result in the production of the extra resources needed to support them. Thus, he proposed that the right to assistance, and therefore the Poor Laws, should be abolished, although assistance should be offered to those who, through no fault of their own, were destitute. However, the undeserving poor - who had deliberately impoverished themselves by having large families or through indolence - were to be abandoned by society. Malthus also proposed that taxes should be raised to educate the poor in the consequences of having large families, in the expectation that this would persuade them from doing so, thereby maintaining their status as valued members of society.
A nature operating under Malthusian restraint would operate for the good of the species. To this end, resources would be shared during periods of shortage to help ensure that valued individuals survived the shortage. Individuals who were not valued would be abandoned, but only if, and after, they had failed to accrue value by responding positively to the effort expended by their conspecifics on them. Within the Malthusian framework, a key to qualifying as a valued member of a population is to know when to reproduce and how many offspring to have. Each individual decides this with reference to the population as a whole. Typically, the reproductive effort of an individual which is optimum for the population will be lower than that which it could undertake. When Wynne-Edwards (1962) proposed that animal populations might behave within what were essentially Malthusian constraints, with each individual unselfishly restricting its reproductive effort such that the population would not outgrow its food supplies, a vigorous debate ensued, which centered on how this behavior could evolve. A major problem was identified: if selfish and unselfish traits are heritable, selfish behavior becomes fixed in a population because selfish parents produce more progeny than unselfish parents. In brief, it became clear that the selfish interests of the individual will dominate the evolutionary process (Williams 1966; Maynard Smith 1976, 1989; Sober 1984). In this debate, Darwinian nature confronted Malthusian nature and found something alien, not a projection of itself. Indeed, it became clear during this debate that unselfish Malthusian altruism was not a requirement for the evolution of reproductive restraint, as it would often be the case that restraint would be in the interests of the individual as well as being in the interest of the group. In this situation, individual selection will achieve what is good for the group. Williams (1975, pp. 126-127), for example, proposes that individual selection can account for female fecundity being below that which is physiologically achievable, in animals in which most of the cost of reproduction occurs after fertilization, the level achieved being ". . . appropriate to resources likely to be available later to the young . . ."
It is important to note, however, that although the Darwinian view of nature does not accord with the Malthusian ideal (a conclusion which would have been unsurprising to Malthus, who considered that reproductive restraint could be practiced only by humans, because only they were rational), Darwin, in the Descent of Man, describes human sociality as having evolved in a way that could result in individuals acting against their self-interest when this benefited the group. He identified self-interest as the most important stimulus for the evolution of human sociality, as individuals who cooperated in groups fared better in the struggle for existence than solitary individuals. Traits selected because they enhanced the success of individuals by increasing their ability to interact socially with group members included the abilities to imitate the behavior of other group members and to respond in an appropriate way to praise and blame from group members. Although these traits became established through individual (as opposed to group) selection, they provide the basis for unselfish behavior: when the interests of the individual and those of the group do not coincide, the threat of social disapprobation for acting in self-interest, or the promise of social approbation for acting unselfishly in the interests of the group, could persuade an individual to act unselfishly; because this behavior receives social approbation, other group members would be inclined to imitate it. Thus unselfish behavior, including bravery in battle (and which would also include reproductive restraint), could become established as a result of social conditioning, even if it was opposed by natural selection (Darwin 1883, pp. 130-132).
Discrepancies between a nature operating under Darwinian theory and under a projection of Malthusian social theory reflect profound differences between the assumptions underlying these theories. In particular, although both Malthus and Darwin agreed that the struggle for existence was a major stimulant of change, their reason for thinking this, and their concept of change, were very different. For Darwin, change included the acquisition by individuals of attributes their ancestors had not possessed. Malthus offered a much more restricted view of change as a process of development (including mental growth), an unfolding of what was already present in an individual and which had also been present (albeit possibly in undeveloped form) in that individual's ancestors. Differences in the perspective they had of the relationship between struggle and change reflect differences in the assumptions they brought to the study of life. Darwin, adopting a scientific approach, assumed that the explanation for natural phenomena lay wholly within nature. Natural explanations were ultimate explanations. For Malthus, natural explanations were proximate. The ultimate explanation lay outside nature, in the guise of a Newtonian God who used struggle in nature to stimulate the full development of His creation. Along with other contemporary social theorists. Malthus assumed that God had provided humankind with a moral sense and a concept of social justice that would ensure that the struggle would result in improvement. Thus, social justice set the boundaries of what had been ordained to be acceptable human behavior. Adam Smith (1790, p. 82-83) described the operation of social justice within a socioeconomic framework as follows: "To disturb his happiness merely because it stands in the way of our own, to take from him what is of real use to him merely because it may be of equal or of more use to us. . . . is what no impartial spectator can go along with . . . In the race for wealth, and honours, and preferments . . . |a man| may run as hard as he can, and strain every nerve and muscle, in order to outstrip all his competitors. But if he should justle, or throw down any of them, the indulgence of the spectators is entirely at an end. It is a violation of fair play, which they cannot admit of." And Thomas Paine, in the opening chapter of the Rights of Man (1791-1792), argues that the natural rights of an individual includes ". . . all those rights of acting as an individual for his own comfort and happiness, which are not injurious to the natural rights of others." Thus, central to late 18th century and 19th century social theory was the recognition that the promotion of self-interest was healthy but needed to be constrained for the good of society as a whole. Darwin's evolutionism was impervious to the metaphysical concepts that lay behind this conclusion. Darwin could accommodate a moral sense in humans but not one that was supernaturally imposed. He argued that it was a product of evolution by natural selection, with the most evolutionarily stable moral sense (i.e., that exhibited by the most successful social groups) being based on the adage "do unto others as you would have them do unto you" (Darwin 1883, p. 131).
Why did Malthus assume that God used struggle to improve humankind? Briefly, he considered that the human mind, like Newtonian matter, was inert and had to be moved (or stimulated) if it was to move (or think). He assumed that God had designed the human body in a way that would enable it to provide the stimulation required for the development of the human mind. The major stimulants were wants of the body which, if absent, would result in a humankind which, intellectually, was ". . . sunk to the level of brutes, from a deficiency of excitements" (Malthus 1798, p. 144). Malthus argued that the struggle for food involves more exertion than anything else, and therefore contributes most to mental development. Consequently, Malthus' God, in order to ensure that sufficient stimulations would be available for the human mind to develop to its full potential. ". . . ordained that population should increase much faster than food" (Malthus 1798, p. 145-146).
Clearly, the metaphysical reasoning behind Malthus' argument that a struggle for existence brought about by overpopulation would stimulate change, and the interpretation he gave to this argument, are fundamentally different to the scientific reasoning and interpretation offered by Darwin with respect to the same argument. But it is worth noting that Darwin's evolutionism and Malthus' social theory share one fundamental concept (in common with other contemporaneous social and evolutionary theories). This is that individuals are the key to understanding nature. This common perspective emerged from the Enlightenment adoption of a Newtonian God. This God adopted a hands-off approach to nature, which He put under the direct control of universal laws (e.g., gravity) or conditions (e.g., the struggle for existence). With God in semi-retirement, secularized interpretations of nature developed. With divine ordinance removed as a mechanism of structuring society (as divine ordinance assumes a proactive God), social theorists came to accommodate the idea that the structure of society was built-up from below. This necessitated that individuals had rights but exercised responsibility. No longer was economic and political power conferred by God. It was a secular power, there for the taking, to be struggled for. Smith's The Wealth of Nations, Malthus' Essay on the Principle of Population, and Paine's the Rights of Man provide contrasting accounts of how this struggle should be resolved.
Once secularized social theory demonstrated the dynamic nature of power relationships within human society, it became probable that such relationships would also be sought within nature. Lamarck's evolutionism fully captures this Enlightenment spirit. Lamarck distilled the secular power and called it the power of life. This molded matter into animate form and stimulated it to progressively and deterministically evolve, via "lower" animals, into human form. In Lamarckian nature species had a right to evolve and to improvement, a right to unfold their potential (the attainment of human status). It was an evolutionism imbued with a natural social justice, a natural moral sense, an evolutionism in which lineages did not justle or throw down each other but ascended the hierarchy of perfection in orderly fashion. There was hierarchy but not despotism, and if one species had to use another, as a predator must use its prey, the interaction was one that was neutral with respect to evolution, as evolution was driven from within - by the power of life - not forced from without. Here was an evolutionism in which the struggle for existence played no part in macroevolutionary change but, Malthusian-like, provided the stimulus for self-improvement; through its own efforts, an individual could make itself a better representative of the evolutionary stage it was at (Bowler 1989). Thus, through their own efforts fleas became better fleas and humans better humans, but through the power of life fleas would eventually evolve into humans. It is here, when humans join with the rest of nature (albeit at its head), that evolutionary theory can become, by projection, a mirror of society and an agent of social change. It is symptomatic that, in the 19th century, teleological Lamarckian evolution was adopted and adapted by social reformers as an analogy for society, given that it was of a social climbing kind (Desmond 1989). It produced the raw material - humans - for social theory. Together they could recreate Eden.
Lamarckian evolutionism, much more than Darwinism, reflected the Enlightenment spirit that also infused Malthusianism and other contemporaneous social theories. But all three were made possible by Enlightenment secularization, which fostered the view that there was scope for beneficial change in nature but that nature had to look to its own powers if these changes were to be brought about. Thus, Enlightenment secularization provides an indirect link between Darwinism and Malthusianism. Each reflected the Enlightenment emphasis that understanding the needs of, and pressures on, the individual was an essential preliminary to understanding supraspecific (population, societies, etc.) phenomena.
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|Title Annotation:||Thomas R. Malthus; Charles Darwin|
|Date:||Oct 1, 1996|
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