Adolphe Quetelet after a lithograph by Madou 1939

Famous Scientists: Adolphe Quetelet

A few weeks ago, I wrote about Bronze Age Peoples, describing how the archaeological evidence indicates that people lived then almost as long as we do today.  The Bronze Age is considered the beginning of civilisation.  By civilisation we mean a stable society, with towns and villages, with a system of commerce and agriculture, a culture and a governance, implying a hierarchy. What is observed, alongside the undoubted benefits of communal organisation and settlement, is the development of divisions in wealth and skills.  Differences emerge between rich and poor, worker and overlord.  Greek and Roman society had slaves to support their civilisation. By mediaeval times the feudal system fixed the entire population in different classes, depending upon their situation in life.  You might be a noble, lord of the manor, perhaps a freeman, or more likely a surf.  Your birth would foretell your destiny.

It is only very recently in history that we find people questioning the class divides.  By the time of The Enlightenment in the seventeenth and early eighteenth centuries, political thinkers had recognised the iniquities in society and sought to remedy them.  For example, in France the concept of Liberté, Egalité, Fraternité, fuelled the French Revolution in 1799. This new-found humanism influenced the thinking of contemporary scientists who  realised that the scientific skills of experimentation, data collection and rational thinking could be used as tools to cure society’s ills.

The brilliant Belgian mathematician, Adolphe Quetelet almost single-handedly invented the science of sociology, and in so doing established the rules of demographics and epidemiology.  Being a mathematician as well as a scientist, he was able to gather population data and, for the first time, reveal that social class, age, where you lived and what you did, all have an impact on longevity.  By using an early version of a census, he was able to show that many features of human existence that we think are self-determined are not.

Quetelet was one of the first people to suggest that we don’t have the free will we think we have.  We are all the victims of circumstance.  Yet, almost exactly 150 years after he published his famous book, Physique Social, while we are now drowning in social statistics, many modern politicians still find it very difficult to grasp this fact of life. In nineteenth-century Belgium, Quetelet was able to show that everything from age of death, height, mental illness and criminology could be predicted by looking at the situation in which people lived.  He realised that this correlation implied a cause – poverty, overcrowding, lack of education and diet.

We think of modern society as more equitable, health as a right, and looking after our own bodies as a subject of lifestyle choice. Many of us want the freedom to smoke, to drink, to eat doughnuts and few equate those choices to circumstance.  But the statistics do not bear this out. It is very difficult for us to escape our situation in life.  Quetelet maintained that,

Free will, whose effects are so capricious when one merely observes the individual, does not leave any sensible trace when one considers a number of people.[i]

In England today issues such as the north-south divide, racial prejudice and gender inequalities are all well documented. We know that re-balancing differences in longevity between the north and the south is not a simple matter. Levelling up will take years. It is likely to require radical changes in our education system, new communications, as well as new opportunities.  And even if all this is achieved, there will be no way to completely even-up differences between north and south due to climate and location.

One of the most obvious north/south health inequalities today relates to people who are overweight and obese.  Quetelet in the nineteenth century set very rigid guidelines for surveying the populous.  But, extraordinarily, in England in 2021 we have no systematic method of recording whether people are overweight.  GPs do make some records, but they are not complete and often wildly out of date.  When did your GP last weigh you? A House of Commons report in 2019 stated that the highest rates of GP recorded obesity occur in the north-east (12.9%), parts of Yorkshire (11.6%) and Merseyside (11.1%). But the same report acknowledged that the figures are wildly inaccurateiii.  We seem to live in a country where national figures of obesity, so closely linked to incidence of COVID-19 death, are considered unimportant.  National obesity figures are an underestimate of the true prevalence. In 2017 an NHS survey of a sample of English people produced obesity estimates of 27% of men and 30% of women. That means that approximately three times as many people on GPs books are obese than are recorded as such[ii].  This has huge implications for the way tackle the obesity crisis.

Quetelet would have immediately seen the links between obesity, unhealthy eating and low incomes and linked it to general health. Food poverty makes it almost impossible to eat a healthy diet.  A family in the lowest rung of deprivation would have to use three quarters of its disposable income on food, if it were to eat healthily (as defined by the Eatwell Guide).   Add other types of deprivation, such as levels of education, depression or lack of employment opportunity and it becomes clear that inequalities of health are very difficult to cure. The House of Commons Report says;

Areas with income deprivation are more likely to have a range of health conditions including serious mental illness, obesity, diabetes, and learning disabilities.[iii]

At present, our government seems to have little appetite to change anything. When in fact many commentators consider that they would have to change everything, in order to make a difference.  No wonder the true statistics are so difficult to find.  Commercial interests are still seen as sacred when it comes to legislation covering environmental, food or healthy initiatives.   It is difficult not to conclude that the UK in the second millennium has not progressed as far as we sometimes like to believe.

However, we can learn from more enlightened countries.  For example, it is no coincidence that Japan, long considered economically successful, now leads the world in longevity.  Prosperity has been shared.  Japan has modernised, but in a culturally sensitive way.  For example, the traditional Japanese diet, considered one of the healthiest in the world, is taught in schools.  Primary school children still have free school milk with their lunch, though today that milk is delivered in recyclable cartons. Part of the luncheon programme is that every child dismantles their empty carton, and folds it away neatly for collection and recycling.   Much effort is placed on teaching children and adults to live sustainably as well as healthily.  There are big connections between the two, that I will go into in future blogs.  Japan was able to act fast because it had the true obesity statistics at hand.  As soon as childhood obesity started to rise, they were able to do something about it.  Education for children and adults, food labelling and exercise all helped change the situation.   Since the introduction of these food education principles at the millennium, Japan has managed to turn back the tide of rising obesity far more successfully than almost any other first world nation.  And its long-lived population are the envy of the world.

A hundred and fifty years ago, Quetelet would have been able to pinpoint the flaws in our modern UK system and in the rhetoric of a modern a prime minister who told the House of Commons on the 22nd September 2020, just before COVID-19 started to rise exponentially into a deadly second wave, Our country is a freedom-loving country.” Doubtless, Quetelet would have responded;

The energy with which we defend our free will is paralysing us, so that we do not see the sociological impacts of different risk factors and in a way, this obscures us from using our reason wisely.  In addition, our belief in free will becomes an obstacle to our regulation of social phenomena, favouring inaction. i

I strongly believe that we can help ourselves to better outcomes. But, on a national scale, we cannot achieve health improvement and a more comfortable longevity for the majority of the population without the support, investment and understanding of government.  Healthy life expectancy in males in the North East is only 59.6 years compared to the England average of 63.4 yearsiii.  In South Tyneside male healthy life expectancy is only 56.8 years[iv].

A long and unhealthy old age is not an enjoyable prospect. Yet, it is not merely in old age that poor health can occur. Sadly, younger people often have to encounter privations very similar to those of the elderly.  Diabetes type 2 can give a 40-year-old the impaired eyesight of someone twice their age.  Smoking can bring debilitating breathing difficulties to a thirty-year-old.  Drunken driving was the cause of an estimated 8,680 people being killed or injured in 2018.  Injuries caused by road traffic accidents blight the lives of entire families. About 30% of injuries occur to those under the age of 24[v].

These inequities were understood in the 19th century, yet today, in the 21st century we still struggle to reconcile ourselves to the realities of social differences.  James van Drunen, in his monograph of 1919, assessed Quetelet’s contribution thus;

 Quetelet was able to see that social factors of all types were not easily observed without resorting to a rigorous analysis, that could break them down into their causative elements.  He was also the creator of the definitive method of statistical analysis in demographic research, the investigative procedures and the basic rules which have since been developed by numerous succeeding disciplines, providing a sound basis for insights and methods that we still use today. [vi]

Quetelet was a polymath and a cultivated man; intelligent, well read and lucid.  He pursued many different passions, all with equal skill. He wrote plays, an opera, he became an accomplished mathematician as well as a social scientist, before the word sociologist had even been invented. His contribution to the science of demography and thus epidemiology is vast.

[i] Adolphe Quetelet 1869 Physique sociale: ou, Essai sur le développement des facultés de l’homme (Social physics: or, Essay on the development of human faculties) Volume 1 C. Muquardt , Demography  Translations by Wendy Shillam see vi.

[ii] Health Survey for England 2017  Summary

[iii] House of Commons Health inequalities: Income deprivation and north/south divides Insight Guide

Published Tuesday, 22 January, 2019


[iv] South Tyneside website: Life Expectancy  quoting ONS 2015 figures

[v] Department of Transport 2020. Reported road casualties in Great Britain: final estimates involving illegal alcohol levels: 2018

[vi] James van Drunen 1919. Adolphe Quetelet, Turnhout Press; Translated from the French by Wendy Shillam 2019, London Library.

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Wendy Shillam

Trained in environmental and bio-sciences, Wendy Shillam is a registered clinical nutritionist, specialising in longevity.  She is the founder of the social enterprise Say Tomato! that provides free and trusted weight loss advice for women over forty.  This part of the blog is a precursor to publication of her book, Glorious Summer – the secrets of longevity.  You can read about it here.


2 thoughts on “Famous Scientists: Adolphe Quetelet”

  1. Thank you Wendy,
    Really interesting. I’ve not heard of Quetelet before. One of history’s overlooked proponents of wisdom and good endeavour.

    From what you say our culture is our downfall insofar as we highly prize our personal freedom, whereas the Japanese, an extraordinary nation in many ways, appear to have a very high regard for self-discipline and team spirit. I wonder where these national characteristics of thought and behaviour spring from, and what the prospect is for overcoming the elements within them that have mutated to do us harm?

    Politicians and the media are quick to label as ‘nanny state’, health initiatives that seek to curb excesses regardless of how sound the supporting evidence for them is. It is so easy to whip up a ‘four legs good, two legs bad’ response to polarise attitudes and frustrate change. As H. G. Wells said, “Human history becomes more and more a race between education and catastrophe” with the former losing ground.

    1. I’m always pleased to hear about someone who is that rarest of beasts – a famous Belgian. Quetelet was a very interesting and thoroughly charming and kind person, by all accounts. Not only did he formulate the mathematics we use today when we run medical trials he also inventned the Quetelet Index, advanced by Ancel Keys to become the BMI – another great statistical leap forward. I’ll be wrting about Keys next week.

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