What was the research and advocacy that took place by personnel associated with UCL and its sister institutions? George Forster investigates Karl Pearson (1907) A First Study of the Statistics of Pulmonary Tuberculosis (Studies in National Deterioration number 2; London: Dulau and Co.). 26 pp.
Following the death of Karl Pearson in 1936, several biographies appeared penned by contemporaries, students, and filial relations. Three stand out: Raymond Pearl (1936), George Yule and Louis Filon (1936), and Egon. S. Pearson (1938). They detail his character, interests, and contributions to respective fields of academia. Pearl encapsulates their thematic dictum, quoting Velleius Paterculus, “Animo vidit, ingenio complexus, eloquentia illuminativ” (1936, p. 653) (“His intelligence saw a problem, his genius encompassed it, and his exposition illuminated it”). These posthumous accounts focus on Pearson’s exposition of statistics as his predominant contribution to society. Later accounts also recognise Pearson’s role in the subject, Norton describing him as “the father of the modern discipline of statistics” (1978, p. 3), but broaden the scope of his exposition to include eugenics, commensurate with statistics. The bifocal view of Pearson’s exposition was concomitant with the condemnation of eugenics as the 20thC progressed. Whilst these early biographies may be criticised for neglecting Pearson’s role in eugenics, Egon was certainly aware of the importance of time in his filial account when he stated, “Nor indeed has the time yet come when any final summary of the value of his contribution to science can be made” (Pearson, 1938, p. 13).
Egon’s account is one of only two book-length biographies of Karl Pearson. Theodore Porter (2004) authored the other, perhaps seen as the chef-d’oeuvre of Pearson biographies. It is the most important account to establish and understand themes in Pearson’s life, simultaneously comparing views of Pearson in 20thC biographies. Porter is not as successful in discussing Pearson’s role in statistics, however, dedicating less than a quarter of his account to the subject, and venturing no further than to describe his contribution as having “helped to create this more standardised world of seemingly interchangeable science” (Porter, as cited by David, 2009, p .38). Nonetheless, Porter succeeds in realising Egon’s augury and challenges descriptions of Pearson as a “disciple” of Francis Galton (UCL Eugenics Enquiry, 2020, p.6), the ‘father’ of eugenics. Building on a portrayal of agency, Porter focuses on the intellectual development of Pearson and, whilst he does not extensively investigate the role
Pearson played in the eugenics movements, establishes two themes that came to undergird his subsequent eugenic pursuits: philosophical beliefs and political orientation.
These themes are succinctly detailed in a later publication by Porter. He describes Pearson as having lived out a Bildungsroman, a novel that deals with one’s formative years or spiritual education. This amounted to an “auto-Pygmalionism” of his scientific work, concurrent with attempts to reconstruct society (2006, pp. 314-321). The description suggests Pearson was a man imbued with romantic, if not quixotic ideas, developed during formative postgraduate studies in Heidelberg, Germany. Here, as a student of neo-Kantian philosophy, Pearson subscribed to Spinozism, a rationalist school of philosophical thought (Porter, 2004) that ultimately underpinned many of his cogent, albeit specious, publications on eugenics.
Conversion to socialism also occurred during this period as he drew upon views of the German socialist left, but interestingly maintained support for ideas of social Darwinism (Kevles, 1995) that were incompatible with this political orientation. Porter, however, fails to appropriately elucidate how this period informed his eugenical and statistical research.
Kevles (1995) provides a more nuanced account of how such views informed Pearson’s work in eugenics, noting how Pearson believed that the achievement of human fitness was associated with nationalist socialism. Pearson’s seminal work The Ethic of Freethought gives credence to Kevles’s observation. Suggesting that Britain was in a state of deterioration as economic incentives left procreation to the socially ‘worst’, Pearson declaims that Britain, as a socialist-imperialist state, should implement national welfare strategies that favour the eugenically desirable (Pearson, 1888). His proto-eugenic leanings arose from his formative experiences (Kevles, 1995), and his relationship with zoologist Walter Weldon resulted in publications to justify his predilection. Notably, Mathematical Contributions to the Theory of Evolution suggested that selective breeding changed the centre of regression intergenerationally (Pearson, 1896), providing empirical evidence for Pearson to argue a fortiori that selective breeding was the principle through which the deterioration of human ‘stock’ should be addressed. In eugenical theory, therefore, Pearson “took his bearings from the past and not only an imagined future” (Porter, 2006, p. 321) to advocate the principles of the subject – from his appointment as the first Galton Professor of Eugenics in 1903 to his retirement in 1933, he published 50 papers on eugenics (Woiak, 2004).
Fears of a dilettante label drove relentless work ethic (Bartholomew, 2005) and production of specious work (Kevles, 1995). Both Pearl (1936) and Haldane (1957) discuss the superficially plausible, yet incorrect assertions made by Pearson in many publications. As former students, their critique offers an interesting insight. Writing two decades after his death, Haldane offers a perspective weathered by atrocities founded in eugenic beliefs.
Pearson repeatedly disregarded nascent lines of research that transpired to be fruitful, and vice versa. Refusing to consider other academic perspectives engendered shortcomings in Pearson’s work, leading Haldane to analogise his fundamentally incorrect theory of heredity to Columbus’s theory of geography (Haldane, 1957). The New World in his case was eugenics. Similarly, Pearl discusses Pearson’s obdurate nature, suggesting that genetics would have been more advanced by the time of his death had he not “unwisely questioned” Mendelian theory (1936, p. 662). An interesting opinion as he described his relationship with Pearson as “discipleship” (p. 664), and especially as Yule and Filon (1936), also former students, exalt Pearson in their contemporaneous account.
The most informative biographies of Karl Pearson are those published at the end of the 20thC, most notably Kevles and Porter, as they review Pearson’s life, work, and consequent impacts through a lens sullied by time. Earlier accounts reveal a stratum of eugenical understanding at the time; limited eugenical discussion, however, was not necessarily indicative of public opinion of the subject, nor suggestive that eugenics had besmirched Pearson. The biographies all conclude that Pearson’s work ethic was tantamount to a Stakhanovite and that he was a brilliant, yet obstinate, teacher. Formative influences in his political and philosophical thinking are also thematic, but earlier biographies rarely exceed rote descriptions, whereas later works explore the relationships between formative years and eugenic advocacy.
A First Study of the Statistics of Pulmonary Tuberculosis (Pearson, 1907) intends to establish whether disease susceptibility, specifically phthisis (pulmonary tuberculosis), is inherited at the same rate as other physical characteristics (p. 4). The verbose body of the paper tacitly suggests an ulterior motive for undertaking this study; a ‘scientific’ document to support eugenic theory and justify future eugenic policies. I have refrained from examining inference or subtext, however, as the final section explicitly confirms a priori allusions that the study is used to advocate for the need to preserve the “reproductivity of the mentally and physically fitter stocks” (p. 26).
Pearson’s inconsistently implements data within loquacious analysis that is thematic of The First Study. Initially, he statistically analyses data (a sample of just 384) from The Crossley Sanatorium, Frodsham, a lower-and-middle-class demographic from Manchester and Liverpool. Although recognising data limitations in the sample size and missing family histories (p. 5), he nonetheless predicts missing values, arbitrarily using Mendelian theory, before basing conclusions on this data. Further inconsistencies arise when Pearson compares unpublished data from New South Wales and Denmark to conclude that individuals belonging to the “artisan” demographic (lower-and-middle-class: another naming inconsistency) were more fertile if they were heterozygous for tuberculosis id est they were not symptomatic, but their children were.
Contradictions are a commonality in this paper. Two notable examples are Pearson’s use of Mendelian theory and his understanding of the role of the environment in diathesis of pulmonary tuberculosis. Firstly, Pearson introduces preliminary statistical analysis using Mendelian theory before suggesting the theory is unfavourable as observed results do not match predictions (pp. 9-10). Despite his repeated polemic, he continues to utilise Mendelian terminology throughout. His results also contradict the increasingly accepted Mendelian theory of inheritance at the time, and his continued use of Mendelian phraseology itself undermines his refutal of the theory. Further, Pearson begins with a critique on what he sees as the overstated importance of environmental factors in contracting tuberculosis, yet later acknowledges the importance of such factors in future data analyses (p. 24).
Pearson consistently casts assertions from inconsistent data. Throughout, he uses terms such as ‘probably’, ‘appears’ and ‘might’ following data analysis then draws conclusions that, given the seminality of the study, had significant real-world ramifications. The ambiguity and complexity within his data analysis, predominantly in terms of sentence structure, is juxtaposed by clearly worded conclusions that illogically follow. Thus, whilst it is not clear nor logical as to how Pearson arrives at conclusions, it is intelligible when he presents one and ultimately clear as to their intended effect. The use of the term ‘we’ stands out as it anchors Pearson and the reader to sections where an assertion is made or where specific data analysis supports such assertions. Given the eugenics undercurrent, ‘we’ provides an impersonality that removes Pearson from relating to the controversial subject at the time. He engages the reader yet makes sure to demarcate his personal involvement at key points, using the first person. Pearson perhaps relies on his reputation as an academic to assure the reader that contentious data and limited sample sizes do not undermine the study’s validity.
A startling aspect is the arbitrariness of data analysis. On the death rates from those affected by tuberculosis, Pearson states, “This is certainly more than 8% and probably less than 13%. I have taken 10% as a round number to start with” (p. 12). Although subsequently qualifying this decision in terms of negligible effects to correlation coefficients, the inclusion immediately casts doubt over data analysed thereafter. Farrall (1965) similarly notes that Pearson’s interpretation of the same correlation coefficient varies depending on whether it supports the thesis he is presenting (p. 256). The nascency of statistical science at the time meant challenging such capriciousness was often the privilege of the statistics vanguard, many of whom agreed with Pearson’s application of such methods to give credence to eugenic theories. Furthermore, Pearson almost solely references his own previous publications, including the journal Biometrika where published articles were subject to his editorial oversight. Given this arbitrariness and biased referencing, Pearson consistently undermines the validity of his conclusions.
“Preservation of the dominant reproductivity of the mentally and physically fitter stocks” (p.26) is the concluding maxim that elucidates Pearson’s view in The First Study. This perspective is also found in earlier publications such as The Ethic of Freethought, where Pearson takes the complementary position that the state should intervene in reproductive matters pertaining to “anti-social propagators of inefficient and unnecessary human beings” (Pearson, 1888, p. 417). Thus, conclusions drawn in The First Study are parti pris, and explain the specious, if not spurious, assertions made throughout. Kevles’s (1995) view of Pearson as a “besieged defender of an emotionally charged faith” (p. 36) is supported by the lengths Pearson goes to give credence to his preconceived views. Finally, there is an unavoidable irony of The First Study found in an earlier work, The Grammar of Science (1892), where Pearson states, “the judgement based upon [the facts] ought to be independent of the individual mind that examines them” (p. 6).
Eugenics was a history of ‘biometricising’ social vicissitudes to justify measures that would “perpetuate an imperially fit nation of British men” (Bashford and Levine, 2010, p.55). Karl Pearson viewed eugenics as a prodigious panacea. In reality, it was a denigrative solution to what he perceived as issues of race and class. Such ‘issues’ arose from an “elite state- socialist” (Norton, 1978, p. 23) perspective held by Pearson that, upon further investigation, cloak the raison d’etre of eugenics: fear. To describe the history of eugenics in one word does not preclude arguments for alternative explanations of the discipline. ‘Fear’, however, undergirded facets such as immigration, racism, and classism that recruited eugenics as a mechanism to abate these issues and their perceived vicissitudes, as Bashford notes, “fears of degeneration […] manifested in race-based immigration controls” (p. 50). The aim here is not to nullify the complex history of eugenics, but to present a view that encapsulates the presentiment of Pearson and his subsequent attempt to transform eugenics from “the playing field of dilettanti and controversialists into a serious branch of science” (Economist, 2014), through biometry and statistics.
Buchanan (2004) presents a compendious review of Porter’s (2004) biography of Pearson, describing the statistician as a “contrary modernist” who “wallowed in a sea of romantic self- consciousness” (p. 3). Such romanticism would have been more aptly described as quixotism until the development of statistics and biometrics towards the end of the 19th Century.
Buchanan, however, accurately describes the formative period of Pearson’s academic life and one where his rationale for eugenics emerged.
In 1879, Pearson travelled to Heidelberg, Germany, where he studied philosophy under Kuno Fischer. Noted for distinguishing empiricist and rationalist views of philosophers, Fischer influentially introduced Pearson and Friedrich Nietzsche to Spinozism. Predictably, the two held concurrent views on matters such as the necessity of hierarchy, political conflict as biological conflict, and agreed that “the creation or furthering of them (persons) is the highest end which men can now propose to themselves” (Nietzsche, paraphrased by Salter, 1915, p. 379). In Germany, “Pearson hoped to find a new philosophy, a new creed that would satisfy his need for something in which to believe” (Norton, 1978, p. 22), resulting in his acceptance of Spinozism. Critically, this philosophical dictum rests on rationalism which claims certain knowledge can be obtained in the absence of experience through principles of deduction.
Assuming ideas correspond perfectly to reality, Spinozism asserts that the laws of human nature “have the certainty, necessity, and the universality of the basic laws of mathematics” (Scruton, 2002, p. 39). An unsurprisingly prophetic statement given the eventual application of statistics and the use of rationalism to justify fears of class and race in eugenics. Ironically Pearson came to rely on empiricism, the counter perspective in a philosophical dualism, to convincingly disseminate rationalist eugenic thought through academic publications. It is, however, within one of Pearson’s first publications upon his return to England that his Spinozist rationalism perspective can be observed in its nascency.
In the absence of statistical and biometric justification and given Pearson’s status as an “elite socialist”, Anarchy (Pearson, 1881) appears more as a soliloquy of fear than a seminal statement in the eugenics creed. An introduction to his eventual Bildungsroman, Anarchy provides an insight into the mind of a preeminent facilitator of eugenics through an axiomatic discussion of the threat of Proletariat uprising in England towards the fin de siècle. The threat is really the fear that a revolution would be “an eruption sufficient to shake the foundations of society and our “glorious constitution”” (p. 269) and challenge Pearson’s social status.
Maintaining a classist lens, Pearson describes Proletariats as “dumb helpless masses” (p. 267) with little value for life expect for “sensual pleasure” of which they “have long ago drained the cup to its very dregs” (p. 269). He infers that Proletariats as “emaciated beings, weak and feeble” view reproduction as a maximand of existence and should they decide to act his “fear that the whole system of society would be paralysed” (p. 270) would be realised. The direct link between the ‘masses’ and fear of uprising does not escape reasoning that Pearson later develops eugenics papers: “dumb”, “weak and feeble”, and replete with “vices”. Contending such ‘issues’ of fear would require a “common religion to draw mankind together and save them from the approaching anarchy” (p. 271). As an agnostic, it would not be a significant stretch to suggest that Pearson viewed eugenics as that salvatory religion.
The ideas presented in Anarchy closely align with Philippa Levine’s analysis of eugenics through an anthropological lens. The Proletariat described by Pearson echoes descriptions of ‘savages’, the derogatory term often used to describe indigenous populations, as “unkempt and unclean, by turns cruel and sensitive, rational and violent” (Bashford and Levine, p. 46). Features of “savages” were central in eugenic discussions: capacity for reproduction, civilisation, and fitness. “Savages” became synonymised with ‘primitive’ and further racialised with the development of eugenics and supporting ‘scientific’ justifications. Levine suggests fear was also the basis of this view, specifically citing Galton who feared that primitivity “lurked within the confines of civilisations” and asserted that, “to have civilisation held back by the undesirable was unacceptable” (p. 51). Galton uncannily echoes Pearson’s view in Anarchy despite never having met at the time. Given their relationship and combined role in the expansion of eugenics, is worth briefly examining some of Galton’s work in support of eugenics as a history of fear.
In 1883, Galton published Inquiries into Human Faculty and its Development, a seminal paper in which he coined the term “eugenics”. Race is a recurrent theme in the paper, often appearing in tandem with pseudo-aphorisms that ‘inferior races’ “swamped” other races, leading to degradation and necessitating selectively breeding ‘superior races’ (Galton, 1883). Galton saw welfare aspects as partly responsible for such degeneration as they had disrupted the process of natural selection (Bashford and Levine, 2010). His consequential suggestion that “if a higher race be substituted for the low one, all this terrible misery disappears” (Galton, 1883., p. 386) could be a synonym, albeit conflating race with class, for “The upper classes themselves must take the revolution out of the hands of the lower and carry it through” (Pearson, 1881., p. 3). Fatalist thinking, such as linking degeneration to extinction, engendered responses including the appointment of the 1904 Committee on Physical Deterioration. This was in part due to fears that a decline in working classes would expose Britain from a military standpoint and weaken the defence of the empire (Bashford and Levine, 2010). The fear of degeneration was transnational and manifested in race-based immigration controls in the early 20th Century. For example, the US Immigration Act (1924) assumed that ‘inferior’ races bred at higher rates than their ‘betters’, congruent with Pearson’s view that Proletariat’s saw reproduction as a maximand. Ultimately, the views of Pearson and Galton were conceived separately yet shared the basis of fear.
Translating such views into actionable processes was contentious and baseless without empirical evidence. As Galton declared, “until the phenomena of any branch of knowledge have been subjected to measurement and number, it cannot assume the status and dignity of a Science” (Galton as cited in Pearson, 1912, p. 2). Justifying eugenic beliefs to a wider audience, therefore, appeared a Sisyphean task in the absence of scientific empiricism. Taken from ‘biologization’, meaning to make biological, ‘biometricising’ refers to the recruitment of biometric approaches (measurements and calculations related to human characteristics) to posit and support theses, in this case eugenic theses. ‘Biometricisation’ succinctly describes Galton’s view of gaining the status and significance of a science. And yet, even with this framework, fear remained and often manifested in vitriolic tirades from themselves and other proponents.
The infancy of biometry and statistics played to the advantage of those who conceived them. Papers based on such empiricism to offer explanations and solutions for social vicissitudes could be seldom challenged. A First Study of the Statistics of Pulmonary Tuberculosis (1907) elucidates this claim. Replete with inconsistencies, inaccuracies, and choice data to support conclusions, A First Study, based on a dataset of 384 people, ultimately asserts the need to maintain ‘fitter’ human stocks through selective breeding. Yet, just two years after publication, Pearson himself claimed, “real inferences cannot, I think, be drawn until we have a random sample of at least 1,000 cases” (Pearson, 1909., p. 55). The specious nature of The First Study led to Squire (1909) to respond, “the statistics upon which they (readers) had been, to some extent, obliged to rely were absolutely fallacious” (p. 60). Pearson’s choice to study tuberculosis is also interesting in observing convergences between himself and Galton. In the latter’s earlier work, he describes those suffering with tuberculosis akin to Pearson’s sardonic disquiet in Anarchy, “considerable proportion of very ignoble specimens of humanity. Some were scrofulous and misshapen, or suffered from various loathsome forms of inherited disease; most were ill nourished” (Galton, 1883., p. 26).
The acceptance of this approach can be somewhat attributed to middle-class radicalism. Often, Pearson occupied the same couches sociale as his readers. His ideas, therefore, were expected to engender a certain type of response that rested on the trust in the scientific author (Farrall, 1965). Coupled with the infancy and nuanced understanding of statistical analysis that was privy to a few, eugenic publications were often foregone conclusions that reflected authorial fears and an affinity with middle-class readers. Thus, the development of biometrics provided an accepted proxy to propose eugenic remedies to social vicissitudes in a time of shared fears. Despite a level of acceptance, near-desperate attempts to justify eugenic thinking remained, manifesting in fallacious statistical analysis and Pearson’s exclusive oversight of publications the Biometrika journal.
Mendelism and the problem of mental defect (1914) and Problem of Alien Immigration (1925) are later works of Pearson that similarly convey a feeling of desperation to convince readers, influence policy and ultimately quell his fears. If, eugenics had been his New World, population control was the Santa María. His specifications aligned with ethnonationalist views that were concomitant with fears that an increasing population of undesirable sects of classes and races amounted to a threat of national collapse; Pearson described the UK as a “crowded island” (Pearson and Moul, 1925, p. 1) being ‘swamped’ by ‘undesirable’ groups. After WWII, however, there was a shift in demographer and statisicians views of human populations that involved a move from ethnonationalist fears to discussing ‘overpopulation’ (Bangham and de Chadarevian, 2014) as a fear unto itself. The rise in overpopulation discussions suggested it was a persistent fear, albeit one that transcended ethnonationalist thought. It was now a fear now founded in a loss of control, from decolonisation, the advent of supranational organisations and rise of Marxism in former colonies. Given the gradual rejection of ethnonationalist fears that undergirded eugenics advocacy, it is hard to disagree that this transition was a realisation of an earlier portent, “eugenics is not a panacea that will cure human ills, it is a rather dangerous sword that may turn its edge against those who rely on its strength” (Boas, 1916, p. 478).
Eugenics was a history of fear implemented through biometricisation. The indispensible role of Pearson and Galton in realising the eugenics movement suggests the discpline was founded in their own views, namely social vicissitudes that they feared would challenge their position in society. Analysing their earlier works revealed an agency with which both proponents developed rationalist perspectives to argue for selective breeding. Such thinking was quixotic without scientific justification. The start of the 20thC, however, provided a perfect storm of middle-class radicalsim and biometricisation that provided an audience and empirical credence for eugenic ideas to flourish. Despite departures from the ethnonationalist undertones of the discipline, other fears that engendered the movement, specifically overpopulation, persisted with the decline of control British imperial control.
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