Mental Deficiency Act 1913 (UK) and Karl Pearson’s Absence

Profesor Karl Pearson at desk in Francis Galton Laboratory for National Eugenics
Profesor Karl Pearson at desk in Francis Galton Laboratory for National Eugenics

I was reading Angelique Richardson’s 2014 TLS piece on the history of the Mental Deficiency Act 1913 (UK), which came into effect 1914 and was repealed in 1968. It inspired me to review that Act and to investigate any involvement by UCL biometrician and eugenicist Karl Pearson in its development and passage. What role did Pearson play in this Act?

We know a lot about the development of the 1914 Mental Deficiency Act (UK). Wikipedia offers a quick entre into the Act. For a more substantial introduction, see Larson (1991). His section “Invoking…” gives a very good summary of Parliamentary activity around this Act. Similar information is available via The Eugenics Archive.

  • Larson, Edward J. 1991. The Rhetoric of Eugenics: Expert Authority and the Mental Deficiency Bill. The British Journal for the History of Science 24:45-60.


In sum, the published evidence showing involvement of Karl Pearson and staff at the  Galton Laboratory for National Eugenics in passage of this Act is weak. There is a need to examine Pearson papers at a letter-by-letter level for related unpublished content to definitively answer questions about his role. In contrast, the published evidence showing involvement of the Eugenics Education Society (EES) is strong. They loudly congratulated themselves for their role in campaigning. Several lines of inquiry offer more details.

Francis Galton and the Mental Deficiency Act

In the last decade of his life, Francis Galton ( supported several strands of eugenics-focused activities. One was via a research centre (hence Pearson, with importance attached to this being legitimated by a university). A second was via an educational group (hence, the Eugenics Education Society, or EES). These two strands (research and educational) did not merge and did not work together as Galton might have planned (e.g., Farrall, Paul, Kevles). On Galton and the EES, historians disagree on Galton’s role. Most historians think Galton was a reluctant figurehead of the EES, as he tended to avoid overt campaigning in favour of education, or eugenics-in-theory rather than eugenics-in-practice (e.g., Waller). He certainly supported and encouraged EES, and basked in the glow of their praise for him. This wouldn’t be the first time a group took on a figurehead, then ran much further than their “founder” might have gone. In this interpretation, Galton functions as a patriarch for the more zealous EES.

Eugenics Education Society and the Mental Deficiency Act

Regardless of Galton’s specific work for EES activities, EES campaigning played a big role in efforts to pass a law in the UK with an eugenics agenda. Woodhouse (1982) provides an excellent discussion of the parliamentary debate and the involvement of EES (as well as other groups):

  • Woodhouse, Jayne. 1982. Eugenics and the feeble‐minded: the Parliamentary debates of 1912‐14. History of Education 11:127-137. DOI: 10.1080/0046760820110205.

On the July 1912 debate, to the Act is noted frequently, but are rarely cited. He specifically criticises the scientific basis of the underlying eugenics agenda.

Party support for the Act was mixed. The Parliamentary numbers published in show the Act with a significant opposition in the first round, when it was introduced as a private member’s Bill. However, there was near complete assent when the Government submitted its own version of the Bill and whipped voting. The pre-war decade was a period of considerable welfare reform by Asquith’s Liberal government. (For a quick entre, see welfare reform.) Eugenics legislation in this case fits into the “improving national efficiency” agenda of reforms in both left- and right-of-the-aisle parties. The right wing of politics was motivated further by a declinist narrative (failure of military interventions; economic competition with Germany and US). The Act creates a convergence of interests. More proximate triggers for this Act surely were (1) the 1912 First International Congress of Eugenics, in London and organised by eugenics campaigner Leonard Darwin, and (2) the report of a 1904-1908 Royal Commission on the Care and Control of the Feeble-Minded. The Government’s version of the Act implemented the Commission’s recommendations more or less in full.

Farrall (1969: 245) argues the passage of this Act represented the “high-water mark for the political effectiveness of the [EES] and the wider eugenics movement” in the UK. He points to Leonard Darwin as the EES’s driving force.

  • Farrall, Lyndsay Andrew. 1969. The origins and growth of the English eugenics movement, 1865-1925. PhD, University of Indiana. Reprinted as Farrall (2019).

Professor Karl Pearson and the Mental Deficiency Act

It appears Pearson had little involved in development or passage of the Mental Deficiency Act. None of the studies I’ve read about the Act mention Pearson being involved in campaigning, nor do they cite his private views on the matter of this legislation. In contrast, Porter (2004, 8) suggests Pearson “refused to compromise himself by joining any movements or by engaging in concrete politics.” I want to investigate the archives before making a more confident assertion, but I don’t yet see any evidence of Pearson’s engagement. I also want to check UoL records to see if Pearson took credit for passage of the Act when reporting to management, regardless of his actual involvement. 

There is a lot of evidence Pearson loathed the EES as unscientific and lacking rigour. He actively prevented staff under his supervisor from contributing to the EES (Farrall; Kevles). When pressed, Pearson seemed to insist on caution and more research through the Galton Laboratory of National Eugenics. Woodhouse (1982) does not mention (a) Pearson, (b) University of London, or (c) University College London in following lobbying of Parliament. The EES archive has no record of Pearson’s involvement. I would think it absurd to argue Pearson was unaware of the Act or that he had no view about it. But I think it’s plausible to suggest he might have chosen to remain outside the political fray and position himself as the sober, cautious, deliberative expert regardless of his views about the legislation. It’s also possible he disagreed with the Act for other reasons, or he worked behind the scenes. (A quick search finds people writing to Pearson about the Act, e.g., Ida Darwin 12/5/1912 UCL Pearson, but I’ve not found Pearson writing much to others. It does not appear he’s trying to steer the debate.)

I’ve searched Hansard for evidence of Pearson’s name or testimony used in the Parliamentary debates. Two hits. Neither to do with the Mental Deficiency Act:

  • – Pearson is mentioned in a floor speech by Mr J.W. Hills during a debate about the “Prevention of Destitution Act”. Hills cites Pearson for arguing that limits on child employment lead to reductions in birth rates for their families (less money=fewer children).
  • – Tuberculosis and Sanatorium Reform – the Galton Laboratory was working on inheritance of tuberculosis. In this evidence, Pearson was cited in a MP’s complaint that government bills were being prepared without sufficient the involvement of scientific expertise.

The interpretation of Pearson as stand-off-ish and the EES lobbying energetically is consistent with Larson’s (1991: 25) analysis of expert testimony in the Parliamentary debate, citing the importance of “civic-minded activists drawn largely from the professional classes,” rather than institutionally based professional scientists, in British political discourse.

Summary and Caveats

Thus, published research offers no evidence Pearson or the Galton Laboratory for National Eugenics played a role securing passage of the Mental Deficiency Act or contributing to the Parliamentary debate.

  • (Can anyone identify contrary evidence? Tweet me @profjoecain)

Some caveats. I’ve not scanned Pearson’s archives in their entirety for direct evidence yet. I’ve not scanned newspapers yet. Lobbying and influence takes many forms; my search has relied on secondary material and published Parliamentary primary sources. Many other avenues might have been used. But, I think this effort is enough to expect, at the very least, the burden of evidence to fall on the positive assertation.

I’m increasingly of the view that Pearson failed to carry much support in the UK eugenics community as a whole, and the Galton Laboratory was not a cornerstone for the eugenics political agenda in the UK. It might have been the functional equivalent of a think-tank, feeding its own material into ongoing debates, rather than maestro of a eugenicist orchestra.

This view helps explain why the fundraising Pearson ran to support the lab in the wake of Galton’s death proved disappointing and lacklustre. The original appeal was for £15,000, according to The Times. When all was counted up, £2,853 was pledged and £1,618 was actually received (correspondence). There are many ways to have influence in the world, of course. In this case, it seems to me, a directly interventionist assertion of influence by Pearson or others at UCL is not yet evidenced.

Related, I have yet to find any study examining the involvement of other parts of UCL or University of London in fostering passage of this act. Help here? Tweet me @profjoecain.