Adolphe Quetelet: Prophet of the New Statistics

background: OCR'ed and edited from 
https://apps.dtic.mil/sti/citations/ADA084771

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Material assembled by Professor F. N. David for her public lecture of April 29, 1980 as a contribution to the celebration of the 150th anniversary of the independence of Belgium.
'''

ABSTRACT 

Adolphe Quetelet (1796-1874) was born in Ghent and was eventually a
professor at the University there teaching mathematics, astronomy, geology,
physics and history of science. He was almost entirely responsible for the
Royal Observatory in Brussels being built in 1826, and became its director
in 1828. An able mathematician, he was concerned also with the collection
of data. In 1829 he drew up the plans for the Belgian census and in 1841
created the Central Statistical Commission. On a visit to London in 1834 
he became one of the founders of the London (later Royal) Statistical
Society and was the first foreign member elected to the American Statis-
tical Association when it began in 1839.

He devoted his whole life to showing how probability and statistical
techniques could be utilized in the development of scientific research
and in government administration. At the meeting of the British Statis-
tical Association in 1841 he listed more than forty topics which he
thought should be investigated using statistical methods -- including

He was the first bridge over the gap between theory and practice of
statistics and did much to create our modern statistical practices.

ADOLPHE QUETELET:
PROPHET OF THE NEW STATISTICS

F. N. David

University of California
Berkeley, California 94720

When I was a young thing at Grammer School we studied the history of
England, classical Gréece and Rome, and, to broaden our minds, we studied
what I might describe as the remaking of modern Europe, beginning with the
Napoleonic period, and continuing through the century. It was in this con-
nection that I first learned about the subject of my talk this afternoon,
and my only qualm is that although he was a Belgian and was responsible to
a large extent for molding and revivifying Belgian science, his thought and
influence was not confined to Belgium, and we really should be commemorating
a great European who was responsible in no small part not only for Belgium
Today but for inspiring and expanding European thought.

I speak of Lambert Adolphe Jacques Quetelet, member of more than 100
learned societies, including the Royal Society of London and the Adademies
of Berlin and St. Petersburg, one of the eight foreign members of the
Academy of Moral and Political Science of the Institut of France, recipient
of an almost innumerable number of decorations and honours. The thing of
which he was most proud was that he was a Belgian. He was born in Ghent
on February 22, 1796, and died in Brussels on February 17, 1874. His father,
who had traveled extensively about Europe as secretary to a Scottish laird,
and who had spent enough time in the United Kingdom for it to be prceble-
matical as to whether he had acquired British nationality, came to Ghent on
the death of his patron, married, and at the time of his son's birth was a
town official of some sort.

Belgium at that time (1796) was part of the Napoleonic Empire. Its
intellectual life had been strongly reinforced by the refugees who tempor-
arily or semi-permanently had exiled themselves from France. I might add
about these latter that it has often been declaimed about the Revolutionary Hl
and Napoleonic periods that the Sciences were never at war. Such theses
as these are based on the flow of correspondence regarding their researches.
between scientists all over Europe and it is often overlooked that a not
inconsiderable proportion of this correspondence concerns possible string-
pulling to try to get fellow scientists out of jail. Napoleon was inter-
ested in Science -- as is witnessed by the number of scientists that he
received as visitors to Paris -- but he did not put scientists to work on
his armaments preferring to gain his victories by new tactical deployment
which did not always work.

The poets and playwrights, who were particularly active in Ghent,
studied and were inspired by the medieval songs and chronicles of Flanders.
Several major poets of the new era lived there so the fact that the young
Quetelet wrote verse and composed the words of a musical drama is perhaps
not surprising.

Quetelet's father died when he was seven years old (1803). There was
apparently enough money for him to attend school at the Lycée at Ghent. He
did well at school and was clearly able in all forms of the arts, showing
at a Salon at the age of 16 a drawing which was the subject of favorable
criticism. However the family income could not have been extensive for at
the age of 17 he obtained a post at a college at Oudenarde, where he was
charged with carrying out a variety of teaching chores. We are told of him
that while he had been very good at mathematics at school and while his
teaching duties were mainly mathematical, mathematics occupied only second
place in his inclinations. He looked on them principally from the point of
view of the money which they would bring him from the giving of lectures and
tutorials. His dream was to shine as a poet and a painter and he spent his
spare time in various ateliers.

Quetelet returned to Ghent from Oudenarde after having stayed only one
year and with no new job to go to. The fall of the Napoleonic Empire (1814)
and the foundation of the kingdom of the Pays Bas caused considerable dis-
organization everywhere. A new city college was started in Ghent instead
of the Lycée and early in 1815 Quetelet became the mathematics teacher there,
at the age of 19. It was now that he came under the influence of Garnier
and that his scientific career really began. William, King of the Pays-Bas,
founded the University of Ghent in 1817 and Garnier was called from France to
occupy the chair of mathematics and astronomy. Garmmier made few significant
contributions to mathematics but he was widely read and knew all the avail-
able sources. More importantly he had a lively and intelligent wit and knew
how to inspire his pupils with the desire to learn. Quetelet, who wanted to
add to his scientific education said that Gamier's instruction really began
when he had lost sight of the blackboard.

In July 1819 he passed the University's first doctoral examination ever
with a dissertation in three parts -- one part astronomy and two parts geo-
metry, including the invention of the curve which he called the ''focale."
The dissertation was an occasion of rejoicing by the professoriat of the
University because of the impression which it made on the outside academic
world and they set themselves to get the young man a place worthy of his
talents. When M. Falck, the minister of public instruction, came in August
to lay the foundation stone of the new university building, they recommended
Quetelet to him with the result that Quetelet was named to a vacant chair of
mathematics in the Athenée at Brussels. Several learned scientists had already
been appointed there.

Quetelet did not, however, give up entirely the pursuit of letters for
some time. He joined the Literary Society, for whom he wrote some poems,
and became a member of a Committee concerned with the theatre, thus meeting
many of the distinguished refugees who had fled from France with the Second
Restoration. But these days mathematics was his chief occupation. Soon
after arriving in Brussels, Quetelet contacted Commander Nieuport who had
almost singlehandedly kept the interest in mathematical research alive in
Belgium. Quetelet submitted a paper to the Academy of Science and Letters
on further properties of the focale and Nieuport and Garnier combined to get
him elected to the Academy in 1820 when he was only 24 years old. He fol-
lowed his election up with several more geometrical papers presented over
the next three years. The Academy is said, at this time, to have been at a
low ebb and to Quetelet is given much of the credit for its renewed activity
and its contribution to the intellectual awakening which was taking place in
Belgium. Quetelet was obviously a man of parts in that in addition to
belle-lettres and mathematics, the Academy sent him in company with Kickx
to write a report about the Grotto at Hahn.

The crucial episode in his life was now almost on him. Quetelet seems
to have been a young man who possessed not only great ability and great
charm of manner, but he also had an almost uncanny prescience in being able
to see how various sciences might develop. Thus he know Mr. Falck, the ;
minister for public instruction, because it was by his influence that he had |
obtained his Brussels post. So he went to Falck and spoke to him of the
necessity of building an Observatory in Brussels. Quetelet had been inter- i
ested in astronomy for some years -- part of his doctoral thesis was on an
astronomy problem -- and he seems to have had little difficulty in persuading
his Academy colleagues that an Observatory would be a good thing. So he was
sent off to Paris in 1823 to find out what equipment would be necessary and
how to work it.

He stayed only a few months but they must have been exciting ones for
the young man. There he met Laplace, Poisson, von Humboldt, Fourier, Arago
and Bouvard, and must have had his first initiation into probability theory.
History does not relate, but it is obvious that also at this time he made his
first acquaintance with Statistics and Epidemiology. Both the Lancet in
London and the Annals of Public Hygiene in Paris were publishing statistical
investigations of various kinds. In Paris was the famous physician Pierre
Louis (1787-1872) justly described as the father of medical statistics and
there were many others. Laplace was playing about, without much success,
with the fittiig of the normal curve to the heights of French conscripts.
Arago and Bouvard were concerned with astronomy data. Quetelet seems to
have absorbed all that was going on. He contributed an article to the Revue
Encyclopedique before his return to Brussels where the Academy gave him the
task of taking charge of the Observatory project. He was then 28 years of
age. His work during the next ten years was phenomenal in output. The same
year as his return from Paris (1824), he was given a chair of higher mathema-
tics at the Athenée and he also started courses of popular lectures in experi-
mental physics, astronomy, and probability at the Brussels Museum. The next
year there were three new research papers in mathematics presented to the
Academy and the beginning of the journal Correspondance Mathematique et
Physique, in coeditorship with Garnier. (Six volumes were published between
1825 and 1830, Quetelet being the sole editor after the first two.) But 1825
was most noteworthy perhaps for the publication by him of the memoir 'Laws
of Birth and Death in Brussels" -- his first statistical demographic paper.
All this time he was also negotiating for the creation of the Observatory which
was officially approved in 1826. He was also organizing simultaneous observa-
tions on shooting stars to be made in Brussels, Ghent and Liege. I think
he picked up the idea of simultaneous observations when he was in Paris and
he was to put it to fruitful use in the years ahead. He presented three more
research papers to the Academy, one being on the geometry of three dimensions
and in addition he drew up a plan for organizing a Museum for Science and
Letters and gave a course there on the history of science. What did he do
in his spare time? Well, he found time to get married and to sire his first
child, his son Ernest.

Possibly after these frenzied three years he wanted a change. Anyway,
in 1827 he took himself off to England to purchase equipment for the Observa-
tory in London. He traveled a great deal about the United Kingdom visiting
Universities and Observatories for about two months. He made the acquaintance
of a great many English scientists among whom almost certainly were Charles
Babbage and Thomas Malthus. On his return to Brussels he was shortly after-
wards (January, 1828) named Astronomer of the Royal Observatory, Brussels.
I noted his first demographic paper in 1825 and as the years went by he swung
more and more to this side of science. This interest must have been accen-
tuated by his English visit, for the english had been busy in this direction
since 1662 and the talk would have been as to how to improve the census which
was first taken in 1801. When Quetelet returned to Brussels from England
he presented papers to the Acadmey called: ‘''Population, Births, Deaths,
Prisons, Poor-houses in the Kingdom of the Pays-Bas," and ''Statistical Re-
searches in the Kingdom of the Pays-Bas.'' This last work was divided into
parts: Population, Taxes and Trade, Books and Journals, Education and Chari-
table Institutions, Comparisons between different parts of the Kingdom. The
introduction was striking in that the author refused to confine himself to
statistical tables but insisted that such tables were the only true base from
which to study human societies. He ended by insisting that a complete census
of the population was necessary. Such a census was decreed in 1828 to take
place in 1830, and Quetelet acted as consultant to the Government on various
aspects of the collection. And again, in case anyone wonders what he did in
his spare time, we have a number of elementary texts -- 1826, Physics Course
in three volumes; 1827, popular treatise on Astronomy; 1828, Popular Instruc-
tion in the Calculus of Probability, this latter some 236 pages long. The
treatise on Astronomy was put on the Index Librorum Prohibitorum by the
Catholic Church, thus ensuring that it had a wide circulation.

When Quetelet was appointed Astronomer to the new Observatory in
January, 1828 he gave up his chair at the Athenée and with it the concomitant
teaching although he kept on with his popular lectures at the Museum for
another eight years. One would have thought that to push the construction
of the Observatory and the installation of the equipment would have been
enough, but that same year he became a member of the Commission for the re-
organization of public instruction. And he did not wait for the construction
of the Observatory to be finished before setting himself to work. In Septem-
ber he started taking geomagnetic observations in Brussels and in a country
house in Ixelles with a view to determining variation, and this led him on to
try to get observations made outside Belgium. So he set off with his wife on
various trips. Before going (1829) he presented to the Academy the last
purely mathematical research paper that he was to write. His biographers
note that his mathematical activity lasted ten years. Given that he did not
seem too dedicated to mathematics as a young man one is perhaps surprised
that the period lasted so long.

The first trip that Quetelet and his wife made in 1829 was to see Carl
Friedrich Gauss (1777-1855) at Gottingen. Gauss had been interested in geo-
magnetism almost since Quetelet was born but had been too active in other
directions to pursue the subject. Quetelet was born but had been too active
in other directions to pursue the subject. Quetelet told Guass what he was
after. This was a new idea to Gauss and so they set up Quetelet's apparatus
in Gauss’ garden and conducted a series of experiments. Gauss is said to
have been astonished at the results and said, 'These observations conform
to the precision of those in Astronomy." From January, 1831, the measure-
ments that Quetelet had asked for were made regularly at Gottingen. Quetelet
visited several other mathematicians and also spent eight days at Weimar
with Goethe, who was then eighty years old. He and the young Quetelet ob-
viously liked one another and there was a happy exchange of letters on his
return to Belgium after the visit. He set out again almost immediately.

The Belgian revolution of 1830 caught Quetelet by surprise, or so it is
said. He was in Rome when it happened, and he went on to Switzerland and
France. He stopped at all the observatories and made geomagnetic measure-
ments at each; these observations were presented in book form to the Academy
of Sciences on his return. When he passed through Paris he left a paper
describing his results which was published some years later (18353) in the
Annals of Chemistry and Physics. On arrival at Brussels he found the Obser-
vatory far from finished, it having been occupied by the volunteer forces in
the independence uprising. Further, and this in the circumstances is also
understandable, administrative difficulties got in the way of the work pro-
ceeding.

There must have been a tremendous muddle for a few months during the
splitting up of the kingdom of the Pays-Bas. From our point of view it was
helpful in that Quetelet found time to catch his breath, and to turn his wn-
doubted abilities to the consideration of many problems of the kind we would
now label as sociological. For as the Astronomer to the University he,
presumably, drew a salary, and his formal duties must have been few. He
set to work to try to sort out the laws governing the physical and moral
development of man, and so in 1831 and 1852 we have papers, "Law of the
Growth in Man,"' "Weight of Man at Different Ages,'' 'Influence of the Seasons
on Man's Faculties,"' and "The Inclination for Committing Crime at Different
Ages .''

It was perhaps the study of crime which led him on to what he called
"social physics.'' He had already written (1828), in his Statistical Researches
in the Kingdom of the Pays-Bas, "that what strikes one most is the frighten-
ing exactitude with which crimes occur. What a sorry state for the human
race. The parts played by the prisons, the fetters, the death penalty,
seem fixed with as much probability as the revenues of the state." He 
repeated these sentiments in 1832, adding that it was necessary to try to
make a reduction in crime.

There were a number of scientists at that time who were already inter-
ested in some of the aspects of the matters on which Quetelet wrote -- Laplace
playing about with the heights of French conscripts, and Malthus with his
concern for world demography, to mention only two. And previously for nearly
200 years men had been looking at birth tables and mortality tables. Count-
ing seems to have been alright for economic purposes, or to find out how
large an army could be mustered, but to look at sickness and death, even if
it was with the idea of trying to enact legislation to improve things, was
to be accused of questioning the inscrutable purposes of God. This intellec-
tual taboo had decreased from the era of John Graunt (1662) but it was still
strong in Quetelet's time. There was also the reluctance of the natural and
physical sciences to have anything to do with the social sciences, an
attitude of mind which still persists. Thus in 1835, a committee of the
French Academy of Sciences reported against any numerical method in medi-
cine "for each patient has his own individuality, problems in medicine are
always individual, the facts presenting themselves for solution one by one,
the treatment in each case depends on a happy instinct supported by numerous
comparisons and guided by experience.'' The great mathematician Poisson was
a member of this committee.

So Quetelet did not face a scientific world entirely at ease with his
new ideas. It is true that Laplace had written in the preface to his book
on probability theory that ''frequency regularities'' imply “constant causes"
in the world of the social side of humanity, and had hinted that a "moral
science'' might be developed, but he did little about it and Quetelet had
really only isolated attempts by many scientists to solve particular prob-
lems as his forerunners. Where his true genius lies is that he saw that by
correct enumeration, any "natural law"' could be investigated and while we
would not perhaps follow him down the path of the ''average man," we must pay
homage to his perspicacity, breadth of vision and statistical insight. Thus
we have him traveling about Europe persuading astronomers and geophysicists
to take various types of measurements with the insistence that these be made
in the same way at the same time. While on his travels, he realized that
the same dictum held for the study of vital statistics and he added it to his
list of objectives. In 1828 he became a correspondent for Brabant in the
Statistical Commission headed by E. Smits and remained a member after the
division of the Pays-Bas. He and Smits were responsible for the report on
the Census written in 1832. But astronomy, geophysics, vital statistics,
demography, and the social sciences did not be any means exhaust his interests.

The British Association for the Advancement of Science -- always
familiarly and affectionately referred to as the British Ass -- met first
in York in 1851. It met every year and in 1833 Quetelet received an invita-
tion to attend as the official delegate of the Belgian government. The
meeting was at Cambridge, so Quetelet went off there, stopping on the way
to deliver a lecture on mortality statistics in Paris. This Cambridge meet-
ing was one which was fraught with significance for the development of Stat-
istics. English statisticians were by and large to be found in the ranks of
the economists. This was entirely suitable for a country that Napoleon
Bonaparte had contemptuously described as a nation of shopkeepers. Quetelet,
on the other hand, was interested in statistics about anything and everything
and, in fact, took with him to Cambridge a list of many subjects which he
wanted his compéres to be persuaded would be amenable to statistical investi-
gation. The subjects ranged from the birth, death and criminality of man
right through meteorology and bioclimatology, the latter in order to be able
to predict when wheat would be ready for harvest and when flowers would
bloom. It says much for his charm of manner, persuasive powers and the
fact that he was previously acquainted with many that he was able to get his
ideas across.

Quetelet found that the British Ass was divided into five sections (A
through E) and that there was no appropriate section where statistics could
be discussed. Quetelet seems to have conferred with Malthus, Richard Jones,
a factory commissioner, a member of Parliament, and Charles Babbage. He
appears to have been on friendly terms with both Malthus and Babbage.
Babbage was interested in statistics from the point of view of the economics
of machines and his and Quetelet's lists of what might be accomplished by
statistical investigation did not coincide. After much discussion between
all interested parties, Babbage suggested that they should Jeclare them-
selves the sixth section F of the British Ass. The general assembly didn't
like this too well but accepted it subject to the proviso that "inquiries
of this section are restricted to facts, relating to commmities of men,
which are capable of being expressed by numbers."' The audiences attending
the meetings of the new section F were comparable in size with those attend-
ing other sections.

Thus Quetelet with his interactions with the English scientists had
started the ball rolling and eventually after he was back in Belgium, further
meetings of interested parties were held in London and the London Statistical
Society was formed in 1834. But Quetelet did not quite understand the
English. On his way back to Brussels he was asked to testify before a
parliamentary committee about the registration -- births, deaths, and so on --
of statistics. In answer to a question as to whether the English were in a
state of destitution in such matters, he replied at length stating "the
very basis on which all good legislation must be grounded has never been
prepared.'' When the Statistical Society was finally formed with the help
and approval of government statisticians, the Tories attacked this statement
and others he had made, and the Statistical Society was landed with the
following: ''The Statistical Society will consider it to be the first and
most essential rule of its conduct to exclude all Opinions from its trans-
actions and publications -- to confine its attention rigorously to facts --
and as far as may be found possible, to facts which can be stated numeri-
cally and arranged in tables.’ Quetelet was elected at once a member of the
Society and in the same year a corresponding member of the British Ass.

Did this Cambridge conference contribute anything to Quetelet's develop-
ment, or was it all one-sided? Well, Malthus died that year, so it is likel’
that conversations Quetelet had with him, recorded many years later, took
place at the conference. Quetelet wrote about the subject of these conver-
gations:

> Statistical documents should be exact and comparable. Comparison
cannot be established in the limits of a single kingdom. Differ-
ent figures are employed to express the same things and nearly al-
ways dissimilar classifications when the most rigorous uniformity
is necessary. This is especially remarked in classification by
ages, in dividing the populations into different professions, in
the nomenclature of diseases, and in that of crimes made known to
tribunals . .. . These disparities are so many obstacles to the
progress of statistics.

We should apologize to his shade since we are not there yet, though we are
trying. He clearly saw what was needed.

Arrived back in Brussels, he went home to the Observatory which had
started up in 1832 although personnel was sparse. Before going to England
he had instituted observations on sun-spots and on his return he created the
publications, the Observatory Year-Book and the Annals of the Observatory,
where the sun-spot observations were published along with others to which
they had led. He was offered a professorship at the new free University of
Brussels but refused. He was then elected perpetual secretary of the
Academy that same vear (1834).

I always have the feeling about Quetelet that sometime he must stop
to take breath and maybe he did just now, although I rather doubt it. But
surely now his lifework must have become apparent to him. There was the
work at the Observatory with observations to be made and conclusions to be
drawn not only about the stars but about climate and the tides of the sea.
There was the work at the Academy. There were the various statistical inves-
tigations concerning the human race and its behavior. And of course, just
as a makeweight perhaps, professorships entailing teaching courses such as
that he accepted at the new Ecole Militaire in Astronomy and Geodesy in 1836.
Here indeed we have a man for all seasons. 1835 was a period of more than
usual activity for him. On becoming Perpetual Secretary to the Academy he
occupied himself with setting the Academy records in order, in publishing
a Yearbook of the Academy, and in writing "Summary of the actual state of
mathematical sciences in Belgium," a paper which was presented to the
British Ass. in the next year, 1835. Quetelet was immensely proud of being
a Belgian and proud of the enormous strides which Belgium was making in
teaching and in developing the sciences. So the paper was probably a writing
down of all the things he had told his English friends during his Cambridge
visit. He also carried out promises that he had made and 1835 saw observa-
tions made on tides on the Belgian coast -- taken at the request of William
Whewell, Professor and later Master of Trinity College -- and hourly meteor-
ological observations made at the time of the solstices and equinoxes --
taken at the request of Sir John Hershel, friend of Charles Babbage. It
must have been about this time when he added a passionate interest in the
periodicities of terrestrial phenomena -- he probably caught it from Fourier --
to his two other hobby horses of multiplication of observations at the same
time and different places and of the standardization of nomenclature for
statistical categories. But 1855 will chiefly be remembered as the date of
the printing of his work in four volumes: On Man and the Development of
His Faculties; or Essay on Social Physics (later to be dubbed by August
Comte in 1838 as Sociology). This is the work which gave incalculable impe-
tus to the scientific world and made Belgian Science -- at least in the
social physics sphere -- a world leader. The four volumes were divided into
physical attributes, moral attributes, intellectual attributes, and a study
of the average man in the social system. I recall with a smile the London
Statistical Society the year before being denied any right to Opinions and
forced to adopt for its crest a wheatsheaf with the motto "Aliis Exterendum”"
-- to be threshed out by others. Quetelet was entirely and wholeheartedly
in favor of the concept of what he styled ''the average man.'"' 'Man carries,
from birth, in more or less the same proportions, the elements of all the
attributes that eventually develope. We have set down divergencies when
they exist but these prove the existence of a general law of development. I
believe it is not only not absurd to postulate this but even that it is
possible to determine the average man of a nation or of the human race."
Again we have, 'Man without knowing it and while he thinks he is acting with
his own free will, is subject to certain laws . .. . that he does not sus-
pect... . If the average man was determined for a nation, he would repre-
sent the type of that nation; if it were possible to determine him for the
whole set of men, he would represent the type for the whole human race."
Now whether we agree with this kind of approach towards solving the troubles
of mankind is at this point in time irrelevant. The important thing to
notice is that in his writings we are given a theory, we are given observa-
tions, and we are given fumblings towards the idea that there should be
some agreement between observation and hypothesis -- this latter an idea
which has not yet been accepted by many even today. Quetelet did not pro-
duce any new statistical theory. Given the way in which he spread himself
T would have been very surprised if he had. He followed the well worn path
first put forward by DeMoivre and attempted the binomial law under various
guises. But, and this is true with much that he did, he foresaw what was
needed to make commonsense of the data of experience even if he could not
carry out his ideas. Probably the Essay on Social Physics was the most
important book for us during the whole nineteenth century, not for what it
achieved but for the signposts which it set up for Quetelet'’s contemporaries
and their successors.

Having, as it were, cleared his mind by setting his ideas about the
average man on paper, Quetelet turned his restless intellect to other things
and did not return to the topic for at least ten years. He set himself to
celestial and terrestrial matters. In 1857 we have a catalogue of shooting
stars, the flowering of plants in 1839, on magnetism and on temperature in
1840, on meteorology in 1841 and a volume On Global Physics in 1842. This
last was an attempt to tie together global physics -- temperature, magnetism,
meteorology -- with the flowering of plants and the behavior of animals,
fishes and insects, and it won him considerable praise all over Europe.
Special reports on it were made to the British Ass. by Wheatstone and to
the Royal Society by Faraday. As usual, the purpose of his writing was to
encourage the taking of observations for the recording of natural phenomena.
The year before the publication of Global Physics (in 1841) Quetelet went
to the meeting of the British Ass. in July at Plymouth and had inserted in
the Proceedings a table of the Principal Phenomena to be observed -- 8 in
meteorology, 7 in physics, 2 in chemistry, 4 in botany, 5 in agriculture,
6 in zoology and 10 in man. and we have the remark, "The idea of filling
this gap in science has long made me sensible of the necessity of establish-
ing as complete an enumeration as possible of periodical phenomena. I have
thought it useful to submit it to the learned.'' At the same time, Quetelet
thought it time that the Belgians should all tell the same time. So between
1838 and 1839 -- at government request -- there were small telescopes set up
in five towns outside Brussels, 41 sundials in other towns so that everyone ‘4
told the same time. We also have an accurate determination of the difference
in longitude between Greenwich and Brussels. And as if this was not more
than enough for one man to encompass, he was lecturing on astronomy and geo-
physics at the Ecole Militaire, he was tutor to the Saxe-Coburg princes
during their visit to Brussels, 1837, and the government sent him in 1839 on
a mission to France to report on the conformity of the weights and measures
standards of Belgium with those of France. During his visit he took the
Opportunity to make some geomagnetic measurements.

Quetelet had been pressuring the Belgian government for some time to
set up a central statistical commission. The commission was created by
the minister Liedts in 1841 and since he had been a pupil of Quetelet's
in the far-off days when he taught at Oudenarde it was natural that he
should appoint Quetelet as its president. In his capacity as President,
Quetelet put forward a proposal to take a general census in 1846 of popu-
lations of men, of industry, and of agriculture. He is said to have taken
an active part in the preparations for this census, publishing an article
describing previous censuses.

This appointment possibly quickened his ideas about moral and political
science and turned him again to social statistics. In 1845, some eight
years after his tutoring, he published in book form the well known Letters
to H.R.H. the Grand Duke of Saxe Coburg and Gotha on the Theory of Proba-
bilities Applied to the Moral and Political Sciences in which he wrote down
what he had tried to teach the young princes. The first nine letters treat
elementary probability, the thirteen following deal with means and limits,
eleven more on the study of causes -- constant, variable and accidental --
and the last eleven on the utility of statistics, dealing for example,
among other things, with the mathematical relation between the fares paid
on the railway and the number of persons travelling. Statistics to him
was the force, both social and political. Obviously following from this
there are several memoirs on free will in the next three years culminating
in 1848 with further ideas about the average man under the title "The
Social System and the Laws which govern it.'' He tried to show the correl-
ation between physical characteristics and the mental aptitude of man.

Quetelet seems to have been uninterested in politics. The happenings
in Europe in 1848 drew from him two papers about the intervention of
governments in people's affairs -- he was against it but these papers are
not noteworthy except that they seem to be the only purely political
papers that he ever wrote. Again having cleared his ideas about the average
man with his further ideas about the social system and mortality tables ;
(1851) and tables of measurements of different parts of the human frame, he
temporarily turned his attention elsewhere. Probably the suggestion regard-
ing "atmospheric waves" came from Sir John Herschel. But Quetelet organized
the Belgian scientists, and later the Europeans, to take hourly readings of
barometric pressures, which led to the advancement of knowledge regarding
storms. Quetelet wrote a memoir called ''On the Belgian Climate" and when
Matthew Maury of Washington suggested an international conference to secure
uniformity of measurement and so on, Quetelet took up the suggestion with
enthusiasm. It was clearly what he had been preaching with regard to all
systems of measurement and he induced the Belgian government to hold a
conference in Brussels in 1853 "to establish a wuiform system of meteorolo-
gical observations for the sea.'' Quetelet was the elected president of the
conference.

As I have remarked several times, one of the main driving forces of
Quetelet was the recognition that statistical knowledge -- and therefore to
him social and economic improvement -- would only come through international
cooperation. He went to London, with the approval of the Belgian Central
Statistical Commission and met with scientists attending the Great Exhibition 
in Hyde Park in 1851. He put forward his international ideas, they liked
them, and it was decided that the first international statistical meeting
should be held in Brussels because of the excellence of Belgian statistics.
Quetelet was given the task of organizing the meeting and he got the Belgian
goverrment to designate it as an International Statistical Congress with
sectional organization and questions for discussion. The government was
responsible for the invitations. The Congress met in Brussels in 1853 and
Quetelet was elected President, a position which he held until his death.
His presidential address dealt with the need for some sort of unity of
terminology in official statistical publications. The Congress was clearly
a tremendous success since it kept on meeting all through the century, and
its influence on the statistics of government -- the bread and butter work
that rules all our lives -- was immeasurable. As usual Quetelet wrote a
paper for the Academy, after this first conference, on the influence of
academies, congresses and scientific conferences. So in 1855 we have a
scientist who through personal charm, immense intelligence, and an inordinate
capacity for hard work, had accomplished more than any ten other men in
pushing the reluctant along what he conceived to be the right road. Perhaps 
he had been happy doing it; probably given his career he had not stopped to 
think about personal ambition but had driven himself as if possessed by a
demon from one task to the next. The years from 1819 to 1855 were undoubt-
edly his career. And now Nature called a halt. 

In July, 1855, Quetelet suffered a mild apoplexy -- a head stroke. He
was found unconscious at his desk. As might be expected this did not con-
quer him. He set to work this time to frustrate his physical misfortune and
because of his affectionate subordinates and his loving wife he succeeded to
a remarkable degree. However his memory, which had been sharp and accurate,
' never really recovered. His prose from being lucid and compelling became
bungling and inadequate, with unfinished sentences. This handicap he
eventually overcame, although for a time his subordinates had to rewrite
his work. Worse still, he was aware of these things and he began to be
suspicious of people who he thought did not pay him sufficient respect.
He might have recovered completely had it not been for the death of his
wife and daughter. As it was, the remainder of his life brought little
that was new to the scientific world and the outpourings of books and papers
were merely revisions of his previous output. His son, Ernest, an able
astronomer in his own right, took over the direction of the Observatory,
although Quetelet remained the titular head until his death. Quetelet limi-
ted himself to meteorology, geophysics and statistics.

Quetelet lived 19 years after his head stroke and when he had gained
some sort of cohesion he played a useful part in the revisions of his books
and in the influence which he had over the statistical world, particularly
the English. Unable to preside over the 2nd Statistical Congress -- held
in Paris -- because of his illness, he presided over the rest -- Vienna
(1857), London (1860), Berlin (1863), Florence (1867), The Hague (1869),
and St. Petersburg (1872). At this last session, the members voted not to
have any more congresses, but to create an International Statistical
Institute with permanent headquarters and this still exists today. So he
lived to see part of his dream become reality.

He must have started on his global work fairly soon after his illness
for he came out with Global Physics in 1861, a revision of his previous
work with additions, a book on the meteorology of Belgium compared with
that of the world in 1867, a second edition of Social Physics in 1869, and
in 1871 Anthropometry or measurements of the different faculties of man;
this last a resume of the measurements he had made between 1849 and 1853
on different parts of the body. In addition he made mortality tables --
mortality tables of Brabant 1859 mortality tables in 1866, on mortality
during the tirst vear of life 1864, mortality tables and their development
1872. There were also a large number of papers comparing and contrasting
the statistics of different countries.

A vast amount of computation must have gone into all this work both
before and after Quetelet's illness. There was some talk with Babbage over
the development of a computing machine in order to reduce census data but
this didn't come to anything. As early as 1838 we have Babbage writing to
Quetelet: ‘I have been so heavily emploved on the great Calculating engine
that I have neglected my best friends.'' So one supposes that all the enor-
mous astronomical, geophysical and statistical computations were carried
out by mortals toiling with books of logarithms, books of multiplication
tables and probably the then modern equivalent of the abacus. It is strange
that we who have so much produce so comparatively little.

The two volumes which did not require any computation but which must
have given him satisfaction as a patriot were the 1864 History of Physics
and Mathematics in Belgium and the 1866 Mathematics and Physics in Belgium
During the 19th Century. These are very much expanded versions of the paper
he sent to the British Ass. in 1835.

I should not end, I think, without speaking briefly on Quetelet's
influence on the development of statistics in England. I have noted his
friendship and influence on Babbage and Malthus and to these I could add
William Farr, the first real epidemiologist. But I must also add two more:
Florence Nightingale, who almost singlehandedly reformed the health of the
British Army, and Francis Galton with his Hereditary Genius and the develop-
ments from it. Florence Nightingale's official biographer writes: Few
books made a greater impression on Miss Nightingale than those of Adolphe
Quetelet. A copy of Quetelet's Social Physics had been presented to her
with the author's hommage, respect and affection. She often spoke of
Quetelet in similar terms. His book was in her eyes a religious work -- a
revelation of the Will of God. In her annotated copy she enlarged the
title. The book was not merely an Essai Du Physique Sociale. It exhibited
"the sense of Infinite power, the assurances of solid Certainty and the end-
less vista of Improvement.'’ She wrote to Galton:

> You know how Quetelet reduced the most apparent carelessness to
ever recurring facts, so that as long as the same conditions
exist, the same "accidents" will recur with absolutely unfailing
regularity. You remember what Quetelet wrote -- and Sir John
Herschel reinforced the advice -- Put down what you expect from
such and such legislation. After x years see where it has
given you what you expected and where it has failed. But you
change your laws and your administering of them so fast and with-
out enquiry after results past and present, that it is all ex-
periment, see-saw, doctrinaire, a shuttlecock between two
battledores.

Perhaps that should be posted in every politician's office.

Quetelet was writing to Florence Nightingale until a few months before
his death, and she was exhorting him to get on with preparing new editions
of his books because the first editions were exhausted. He went off in 1872
to the St. Petersberg Statistical Congress and was received evervwhere with
great acclamation and honor. However, in 1873 when he was asked to organize
a similar congress for meteorologists in Vierma, he did not feel up to it,
although this was one of the things for which he had worked, and he was
represented by his son. His plan for the observation of terrestrial
phenomena was the central theme of the Congress. In spite of his refusal
to go to Vienna, there was nothing to indicate that his end was close. The
eclat with which he had been received at St. Petersberg had had a happy
influence on his morale and he appeared rejuvenated and continued to work
in a tireless way. However, in January 1874, he caught pneumonia and died
on February 17th. His biographer and friend wrote in his eloge:

> The loss of Quetelet has been vividly felt. His writings had
put him in rapport with savants of the whole world. His corres-
pondence was immense. He was known personally to the greater
part of those men who have made a name in science, letters and
the arts whether he had met them on trips to England or on the
continent of Europe, or whether they had visited him at the
Observatory . . . . Belgium should be proud of such a man.

And we might add not only Belgium but the rest of the world. It has
always been said that the stability of government rests not with the poli-
ticians but with the permanent civil servants. For politicians may come and
go, but the permanent civil service is permanent and there is little politi-
cians can do to alter what type of information it collects and how it col-
lects it. Quetelet's lifelong crusade made it almost certain that informa-
tion for government was collected properly and in a way that made in inter-
changeable between nations. We all owe him a trememdous debt of remembrance
and gratitude for his inspiration.