Darwin has been linked to a variety of European movements but, argues John Burrow, their readings of his work, particularly those of 20th-century eugenics - which at its most extreme led to genocide - all involved a distortion of his writings.
The impact on the life sciences of the Darwinian theory of evolution by natural selection is a classic case of a scientific revolution. As with the Copernican revolution, a pre-existing paradigm, to use Thomas Kuhn's term, namely creationism, was, as it were, turned inside out. The taxonomy of the living world, past and present, was transformed by being regarded as the product of branching descent. The match between the internal and external conditions of life for the organism and the species was reinterpreted in terms of the automatic operation of natural selection on random variations in offspring rather than as the will of God.
So much is obvious and nothing in this article is intended to belittle it. But closer up, as it were, the impression of simplicity dissolves rather rapidly. For the revolution's initial context and its wider ramifications were complex and the latter sometimes unwarranted, contradictory or difficult to distinguish from the products of other influences. In the later 19th century, in particular, when applications of supposed inferences from Darwinian theory were attempted across virtually the whole map of knowledge, including its outlying and debatable territories, particularly in the human sciences, the results were often contentious, abortive, otiose and in some cases atrocious.
To begin with the context: creationism, which Darwin rather caricatured in The Origin of Species (1859), was by the 1850s not only under challenge but beginning to develop variants that held the possibility of modulation in evolutionary directions. In France and Germany evolution, or to use the contemporary term "transmutation", was already represented or at least adumbrated by powerful and distinct intellectual traditions.
Seen from a European perspective, England, which had experienced a religious revival in the early decades of the century, was, along with the United States, the home of a Protestant biblical literalism. Darwinism was obviously corrosive here, but only in the wake of geology and critical biblical scholarship. In the long process of what it is easiest to call secularisation, it is hard to assign its proper weight to Darwinism, not least because social factors were relevant also: the drift of the working class from country to city and the eventual erosion of the economic base of the middle-class Victorian patriarchal family.
In France neither evolution nor the philosophical materialism often treated as an inference from it were new. Darwin was disappointed by the reception of his book there, where the influence of Jean-Baptiste Lamarck's version of evolution for a long time exceeded Darwin's. Some leading French figures like Claude Bernard and Louis Pasteur ignored Darwinism or remained agnostic. The issue of evolution became entangled with the contemporary preoccupation with the spontaneous generation of life. If the emergence of indisputably living organisms from chemical compounds could be demonstrated, then a bridge would be built between chemistry and the living world. The latter could be thought of as related by an unbroken chain to the laws of physics and chemistry and the concept of the distinct creation of organic life could be disposed with. This was an important issue in French biology in the mid-century; the alleged experimental evidence for the occurrence of spontaneous generation was demolished by Louis Pasteur. Darwin remained reticent on the issue.
Since the 18th-century Enlightenment, there has been a materialist strain in French intellectual speculation, epitomised in the aspiration to reduce the phenomena of human consciousness and volition to the operation of physical laws. It was in part an aspect of the long hostility of the French intellectual class to clerical authority and influence, which it equated with superstition, bigotry and political reaction. Anti-clericalism was the badge of French republicanism since the time of the first French revolution, but particularly so from the 1850s, when Napoleon III was able to enlist the church in support of his autocracy.
Darwin was assimilated to the materialist traditions of militant French anti-clericalism, notably, to his annoyance, by his idiosyncratic and intrusive translator, the formidable Clemence Royer. In general, the impact of Darwin was much less in France than in Britain, Germany or Russia.
Developments in the sciences fostered a materialist climate of thought in Germany from the 1850s. In physics, formulations of the law of the conservation of energy encouraged the notion of the universe as a self-regulating energy-system, and of all phenomena, including consciousness, as transformations of energy and matter. Developments in chemistry, in cell theory in biology and in experimental neurology all seemed to promise a future unification of the sciences, in which human consciousness would be included, as a series of causal links, without any hiatus, from the highest-level laws of physics to the complexities of human thought and behaviour.
Though not itself evolutionist this materialist climate of thought prepared the ground so Darwinism made rapid headway in the German scientific community. Some materialists even found it insufficiently far-reaching, tending to prefer the directly modifying influence of the environment to natural selection, as more mechanical. The leading materialist, Ludwig Buchner, regretted that Darwin had not traced the origin of life to a single, spontaneously generated form; he had remained too creationist. Everywhere Darwin's achievement in eliminating teleology, or any suggestion that nature shows signs of divine design, from evolution through the concept of natural selection, was widely ignored or misunderstood. The divergent, branching tree with which Darwin illustrated his conception of evolution in The Origin was tacitly, or even explicitly, replaced by an image of a single, central line of the development of life, culminating in humanity.
The employment of the concept of evolution in the second half of the last century was immensely wide-ranging. The ideas of evolutionary sequence and descent, of adaptation and inheritance, and the more specifically Darwinian-sounding ones of selection and survival-value, struggle and competition were appropriated across an immense range of inquiry. Archaeology, anthropology, psychology, philosophy, sociology (whether as a comprehensive account, in the manner of Herbert Spencer, of "social evolution" or in support for eugenics) all felt the impact or in some cases were virtually created by these ideas.
Relations between states, nations, "races" (often scarcely distinguished), classes and individuals were posited in what were intended to be specifically Darwinian terms.
"Psychology will be based on a new foundation," Darwin wrote cryptically in the conclusion to The Origin and tried to show what he meant in The Descent of Man. But taking the statement in its broad sense, as a recommendation for the idea of evolution, he was already a little late. The pioneering work in England was Herbert Spencer's The Principles of Psychology (1855).
Spencer's Lamarckian insistence on adaptation by repeated experience, leading to the foundation of reflex responses and their inheritance, and his own, idiosyncratic, non-Darwinian definition of evolution, left powerful traces, not only in psychology but across the whole of the human sciences, complicating considerably the question of the extent of Darwin's influence. The concept of the unconscious mind, for example, which became influential from the mid-century onwards, was a Lamarckian (in some cases Schopenhauerian) concept more than a Darwinian one, though it was certainly seen in evolutionary terms.
More distinctively Darwinian perhaps were developments in philosophy. The increasing repudiation of a naively positivistic conception of concepts and theories as pictures of material reality (already, of course, adumbrated in Kant) was accompanied by a turn towards a pragmatist view of concepts and theories, including scientific ones, as essentially adaptive devices, tools in the struggle for existence. This was, of course, a somewhat rarefied development.
More characteristic and certainly now more notorious, as wider appropriations of Darwinism, were the uses to which it was put in social and political polemics, in the vindication of imperialism and, most systematically, in the eugenics movements that spread across Europe in the later 19th and early 20th centuries.
The international interest in eugenics (christened by Darwin's cousin Francis Galton), as the control of breeding to arrest an otherwise irresistible tendency to degeneration of the human type, ran the full gamut of the political spectrum. It was a somewhat paradoxical outgrowth of Darwinism. Darwin's conclusion to Origin was an optimistic one. Evolutionary change, being adaptive, operates always and only to the benefit of the organism. But the background to the eugenics movement was the late 19th-century panic over "degeneration", which in turn reflected a middle-class fear of the poor, disease-ridden, feckless populations of the great cities whose uncontrolled growth was a feature of the period.
Eugenics was Darwinism stood on its head; one decided who should breed and rear offspring and then tried to arrange the environment accordingly; it was akin to what Darwin in Origin had called "artificial selection". The "Darwinist" justification for this was that in human societies natural selection was largely suspended; the society itself, its rules and conditions, form the most important part of the controlling environment. But inadvertent social selection may run counter to what nature would have selected if given a free hand - not to mention what the influential members of a society wished to see as its future. Social selection, if not consciously controlled, might, by the preservation of the less "fit" (Spencer's phrase) and their offspring, ensure not evolution but degeneration of the breeding "stock". The breeding of the less fit, degenerates, must be prevented.
Apart from the non-interventionist eugenics of the withdrawal of the state from the support of the indigent there were also "negative" and "positive" versions of eugenic intervention; the former concentrated on such issues as sterilisation, segregation and obligatory medical tests before marriage. Socialists and nationalists, however, sometimes also supported bounties for healthy couples to produce offspring and state-provided maternal care. Eugenic concerns, like the reception of Darwinism generally, were conditioned by local circumstances and anxieties: in France a declining birthrate, in Britain the apparent outbreeding of the educated by the lower classes, in Germany the influx of immigrants from the East, especially Jewish.
Social Darwinism, generally, is difficult to handle because it is so diffuse. In the frequent attempts to apply the concept of struggle, with the authority of science, to social problems, either as a bracing warning or more generally as the supposedly necessary condition of progress, many ambiguities remained. Indeed the ambiguities were responsible for the widespread popularity of the practice and the invariably inconclusive polemics it generated. For there were two crucial and almost unnoticed weaknesses in all attempted social applications of Darwin's concept. When invoked as an explanation of historical change or "social evolution", it yields only a platitude; when invoked polemically, as a prescription for survival of a particular group or the continuation of progress, it merely produced arguments as contestable as the positions they were called on to support.
In biology, where the relevant situations can be precisely specified in terms of reproduction, variation, adaptation, survival, breeding, and where the theories it replaced were mainly creationist or teleological, Darwinism was revolutionary. In social life, providential and even teleological arguments were much less common; social explanation was more sophisticated than explanations in biology until the 19th century, and the fact of change was uncontested; the relevant factors, however, reproduction and the rest, were for the most part only employable as metaphors, and debatable ones at that.
In social life, accordingly, the theory of environmental selection amounted only to the claim that innovations prospered when circumstances were propitious; no methodological revolution followed. Much more popular and frequently urged by what the French called the "struggleforlifeurs" (a picturesque phrase for those who believed in life as a struggle for survival) were allegedly Darwinian prescriptions for ensuring that the supposedly inexorable conditions for success in the struggle were met, ie that society encouraged unfettered competition.
Darwinian principles were invoked to defend social hierarchy or to attack it (depending on whether it was thought "natural" or "unnatural"); to condemn state intervention and welfare or to demand them; to justify extreme individualism or to denounce it. They were called on in social, economic, international, racial, imperialist and colonial contexts (where indigenous peoples were sometimes said to "disappear" by evolutionary law with the advance of the white man). Extreme laissez-faire theorists, statists, nationalists, utilitarians, racialists, anti-humanitarians, even utopian believers in a future of universal peace and cooperation found something apparently Darwinian ready to hand.
The reason for the universal applicability (or non-applicability; it was the same thing) of "Darwinian" principles in social life is very simple. What Social Darwinists chiefly argued about, without consciously putting it in those terms, which would have given the game away, was which form of competition was desirable and ensured progress or, if one adapted to it successfully, survival, and which types of competition should be suppressed; to have recognised them all as potentially operative, as a Darwinian would do in biology, would have removed the point. No respectable Social Darwinist endorsed successful private criminality, though the occasional young nihilist may have spoken in that way; laissez-faire theorists expected law and order at home and tended to deplore international competition as promoting state activity, and imperialism as protectionist. Nationalists tended to favour state intervention in the interests of a healthy and united people, and for the sake of, to use the phrase popular in Britain in the early 1900s, "national efficiency". Enthusiastic colonialists did not always applaud political empires, sometimes deploring their multiracial character. One could go on multiplying examples.
Self-evidently Darwinism cannot adjudicate between such competing claims; the form such arguments took was first to decide whom one wished to be the victors or survivors, and then to endorse or condemn types of competition depending on whether they seemed likely to ensure the desired result. They could assume this form because there is no clear answer, in human society, to the question "between what does the struggle take place?" - human beings have many roles and can be grouped in a number of different ways - any more than biology afforded any answer to the question of what were the desirable or legitimate forms of competition. The human ability to control competition, though in a sense a weapon to use against opponents in a struggle for dominance, is one that has little counterpart in nature, and the use of moral preference to justify such control is unique to human beings.
Though intellectually inconclusive and resting on a mistaken analogy, the use of Social Darwinist rhetorics in the late 19th and early 20th centuries was not, so far as one can judge, negligible in its consequences. For those who used them or took them seriously they tended always to raise the stakes; to create a sense of permanent crisis and to make vast issues of progress or retrogression, of national, cultural or racial triumph, survival or extinction appear to depend on policy alternatives. Crimes against the law of life and death were always, in this rhetoric, punished with extreme, inexorable and irreversible severity.
The over-extension of Darwinism has, of course, brought its nemesis. Eugenics is tainted, presumably irretrievably, by its association with genocide. It was interesting, though not remarked on, that proponents of the free market and anti-welfarism in the 1980s avoided the hereditarian, Malthusian references to the breeding habits of the poor, which in the later 19th century had been a staple part of such arguments. When the late Sir Keith Joseph failed to observe this reticence he was thought to have been tactless.
In international affairs, world war and the invention of nuclear weapons - in making the concept of a war to extinction more vivid and plausible - have also made it less popular. Ideas of racial superiority and inferiority, though hardly extinct, are deeply unrespectable in a post-colonial era. Social Darwinism did not originate such ideas but it had easily assimilated them as the consequence of different turns taken in human evolution. The 19th century, even before Darwin and certainly after him, was the great age of physical and hereditarian explanations of cultural traits. Such explanations were freely applied to human aggregates confidently if fuzzily defined as "races", as well as to distinctions of sex.
Inevitably, Darwin's theory was subjected to searching criticism in the decades after its publication. The most disturbing, which troubled Darwin greatly, focused on the (still not understood) causes of the occurrence of the mutations natural selection worked on. It seemed that, once given the occurrence of a useful mutation, its chances of being passed on in the subsequent generation would be halved, and, in the next generation, halved again, until it was "bred out".
Darwin worried at the problem of the mechanism of inheritance but bequeathed no usable ideas in this context. It was not until the early 20th century, with the recognition of geneticists reviving the long-neglected theory of Darwin's contemporary, the Moldavian monk Gregor Mendel, that genetic material was not "blended" in reproduction but remained discrete and hence available to recur even when not manifested in offspring, that an answer to the problem compatible with Darwinism was found. If the phrase "Darwin's century" is taken as referring not to the appearance of the theory but to its consolidation and dominance, it applies more to the 20th than to the 19th century.
Nonetheless, the late 20th century has seen an emphatic return to the 18th-century disposition to prefer cultural-environmental explanations of human difference. That most difference is socially rather than biologically constructed is not only what we appear to believe but what we strongly wish to believe. How far this will prove in the long run sustainable in the face of the power of genetic and biochemical explanations will surely be on the intellectual and cultural agenda of the 21st century.l J. W. Burrow is professor of European thought,University of Oxford