Hora est! On dissertations
600.000 dissertations in Leiden University
Five centuries of dissertations in Leiden:
A mirror of academic life
If you attend a doctoral ceremony at a Dutch university these days,
you witness a ritual which concludes a research and writing process of
several years. Over the past century these ceremonies have always
centered around a dissertation. Many people are unaware of the fact that
the dissertation in its current form (1) had eight centuries of
predecessors. Various names were used in this long period, disputatiobeing
one of them.
We know how this ceremonial developed at universities in the Middle
Ages. Lectiones (lectures) were frequently concluded with a
scholastic disputatio. From the end of the thirteenth century the
questio disputata, which had started out as a report of the
discussion, acquired a more independent character. This meant that the
disputatio (2) was institutionalised. “After the initial
arguments pro en contra [presented by the magister]
a respondens took the floor to formulate and defend his position
and subsequently refute the counterarguments which the opponentes
put forward against his argumentation.”(3) In the determinatio,
which followed later, the viewpoints, arguments and lines of reasoning
were laid down.
The disputatio as a concept changes its form and
character in later centuries. It basically remains a public academic
debate about a clearly defined subject on the basis of a text at hand,
including – until the 21st century – a character acting as the
The texts of the dissertations handed down over the past five
centuries show a wide diversity. They range from one sheet of paper with
around ten propositions to volumes of over a thousand pages. Authorship
is often ambiguous; a disputatio dating from the seventeenth
century or earlier cannot always be attributed with certainty to a
specific author, even if it does have a title page. Well, even at the
end of the twentieth century the lament could be heard that the
supervisor had completed the dissertation, but that the Ph.D. student
had not yet written it up. In that respect there is nothing new under
For ages authors of dissertations have put their thoughts on paper.
As fledgling scientists or scholars they thus contributed to the
innovation of their discipline. Some of them were even awarded the Nobel
Prize (Marie Curie-Skłodowska in 1903). Universities collected these
writings and university libraries added them to their collection.
Moreover, they often used copies of dissertations defended locally to
trade them for dissertations, book series or journals from other cities
or countries, and hence acquire academic expertise from elsewhere. (4)
Leiden University library was no stranger to this custom of
exchanging books. It lasted until 2004, when the joint Dutch university
librarians terminated the exchange of printed editions. The Leiden
collection contains an estimated 600,000 dissertations, which is around
20% of the total number of books. (For this calculation I have put the
total number of titles at roughly two million and the total number of
volumes at three million.) More than three quarters of these 600,000
dissertations – mainly those defended at universities abroad – have not
been catalogued. (5)
Almost 100,000 of these 600,000 dissertations are works defended at
Dutch universities between 1575 and 2005. The Leiden collection of Dutch
dissertations is made up of 15,000 dissertations from Leiden, 12,000
from Utrecht, 10,000 from the University of Amsterdam, 5,000 from the
Free University in Amsterdam, 8,000 Groningen, 6,000 Nijmegen, 3,500
Delft, 3,500 Rotterdam, 2.300 Eindhoven, 1,800 Wageningen, 1,500
Maastricht, 1,200 Tilburg, several hundreds from Franeker, Harderwijk,
Breda, Bandung, Apeldoorn, Deventer, Kampen and Batavia/Jakarta. Several
thousands of these nearly 100,000 dissertations have never been
catalogued in Leiden. These are mainly dissertations from the
seventeenth, eighteenth and nineteenth century from the university
cities of Groningen, Utrecht, Amsterdam, Harderwijk, Deventer, Apeldoorn
The collection of international dissertations in Leiden cannot be
characterized in just a few sentences. Some 100,000 dissertations from
Germany, France, the United States and various other countries have been
catalogued normally and can be found among the other books in the
university library. It would not be easy to recognize them as
A major part of the international dissertations have been placed
separately in the central repository of Leiden University library. It is
a huge quantity: exactly 700 bookcases, amounting to a four kilometer
row of books. (6) I would estimate their number at around 400,000. Only
6,000 of these have been catalogued and put back into this huge
collection of dissertations; most of the 400,000 have never been
In summary, the Leiden collection contains some 600,000 dissertations;
of the 100,000 dissertations defended at Dutch universities 95% have
been catalogued and hence can be found in the on-line catalogue by title,
author, subject, discipline or university; of the 500,000 dissertations
defended at universities in other – mainly European – countries only an
estimated 20% have been catalogued. (7)
The situation described above raises five questions: Where did these
international dissertations originate and from which centuries do they
date? How did they arrive in Leiden? Why is it that so many of these
dissertations have never been catalogued? How complete are these
collections for each university concerned and how is the situation in
other Dutch libraries? What is the importance of the collection and are
there any treasures hidden among these enormous quantities? In the
following I will try to answer those questions.
City and period of origin
The dissertations are from about 170 cities. Twenty of these are outside
Europe (e.g. Algiers, Baltimore and Johannesburg). Most dissertations
are from Germany (70 universities) or France (35 universities).
Virtually absent are dissertations from Italy, Spain and England.
The oldest dissertations in this uncatalogued collection go back to the
late sixteenth century (Basel, Strasbourg). Thousands of them date from
the seventeenth and eighteenth century: from Duisburg, Erfurt, Frankfurt
(a/M), Freiburg (i.Br.), Geneva, Giessen, Göttingen, Heidelberg, Jena,
Kiel, Königsberg, Louvain, Marburg, Paris, Prague, Rostock, Tübingen and
various other cities.
How these dissertations found their way to Leiden is not a complete
mystery. Several nineteenth century annual reports of Leiden University
library refer to the acquisition of dissertations as part of an exchange
with other universities in- and outside the country. In view of the
numbers concerned the large majority of dissertations acquired in the
nineteenth and twentieth century must have been obtained through
exchange programs with other universities. I would not rule out that
this is also the case for many of the dissertations from the previous
centuries. There may well have been such an exchange even under a
librarian like Fredericus Spanheim (1672-1701). However, it stands to
reason that part of these works have entered the library as part of a
bequest or as a donation from professors, especially in the seventeenth
and eighteenth century. (8)
Why did the Leiden library keep these hundreds of thousands of
dissertations without ever cataloguing most of them? That is probably
due to four factors. First of all, the huge numbers pose a problem.
Besides, in the sixteenth and seventeenth century these works were not
considered to be of great importance, barring the dissertatio pro
gradu (for an academic degree). Thirdly, once a certain procedure
("do not catalogue separately unless otherwise indicated") had been
established there was a tendency to follow it for centuries. That may
have been the case in Leiden, too. And finally, the dissertations had
always been stored by city and by year, so you could easily find one if
you knew who had written it and in what city and what year the doctorate
had been obtained. At the end of the nineteenth century the status of
the dissertation changed and the titles of the Dutch dissertations (and
of a selection of the international ones) were properly entered into the
catalogue. In our day and age the academic significance of dissertations
is viewed in diverse ways. On the one hand there is criticism about the
huge quantities produced (250 per university per year is not exceptional);
on the other hand there is appreciation for the high standard of the
How complete is the Leiden collection of international dissertations
for each university represented?
Despite the huge quantities it is still better to speak of the degree of
incompleteness. Numbers vary enormously between universities: from
around a dozen dissertations (Annaberg, Buenos Aires, Ingolstadt, St.
Petersburg) to several dozens of bookcases full of them (Basel, Berlin,
Duisburg, Greifswald, Heidelberg, Jena, Kiel, Marburg, Montpellier,
Strasbourg, Tübingen, Würzburg). The thèses from Paris fill no
fewer than 120 bookcases. Obviously these are not all masterworks, but
in 2004 we found fifteen gems among this mass, including the
dissertation of Marie Curie, which in the year of its publication
brought her the Nobel prize. It was filed under the S among the Paris
dissertations of the year 1903. In the hundred years that had passed
since then nobody had taken the trouble of looking under her own name (Skłodowska).
Other Dutch university libraries have pursued widely varying policies on
international dissertations. In Groningen all dissertations are regular
items in the collection and in the catalogue. The Utrecht university
library has between 750,000 and one million international dissertations,
most of them uncatalogued. (10) They are from Germany, France, Belgium
The University of Amsterdam library held a clearance operation some
years ago: the collection of international dissertations (total shelf
length 2.5 km) was inspected first by their own subject librarians and
then by staff members of the Koninklijke Bibliotheek (Dutch national
library). Whatever was seen as important in the year 2000 was included
in the respective collections – totaling some tens of thousands of
dissertations. The rest was disposed of (in library terms: deselected).
What is the importance of the Leiden collection?
The importance of the collection of international dissertations in
Leiden cannot be overestimated. It could be used for various types of
research. Per city, per region or per period a researcher can see how a
specific field developed; how research in a certain specialty reached a
deadlock or, conversely, made huge advances; what issues were considered
of academic interest in a specific decade. If you want to do research on
German dissertations from between, say, 1750 and 1936, you can come
browsing in Leiden. It is possible to research the development of
medical science in France between 1900 and 1920. The thousands of
dissertations from the sixteenth and seventeenth century in particular
open up huge possibilities. The American historian Joseph Freedman did
research in these works in 2004 and came to some surprising conclusions
about changes in the academic process in the sixteenth and seventeenth
There is also a significance that goes beyond the Dutch national
borders. Some collections from university cities kept in Leiden are no
longer present at their place of origin. This may be simply because not
all old dissertations were retained (the Leiden collection of
dissertations defended in Leiden is also incomplete!), because the
universities no longer exist, because the library in question was
destroyed (some German cities in World War II), or because owing to
geographic changes preserving the 'old' cultural legacy was not given
priority (Breslau/Wrocław, Königsberg/Kaliningrad).
A search for well-known authors in this collection frequently leads to
the discovery of real gems. This happens on a weekly basis following
requests from researchers in Leiden, but findings also occur in other
ways. In 2004 Leiden University library staff members held a targeted
search for around a hundred named authors among the uncatalogued
dissertations. This led to dozens of discoveries: the first steps on the
research path of eminent scientists and scholars, including Nobel
laureates, such as Bergson, Bohr, Curie-Skłodowska, Durkheim, Einstein,
Hahn, Lewin, Planck, Plessner, Pirandello, Stresemann, Warburg, Weber,
Wegener, but also of a controversial researcher like Carl Gustav Jung.
It should be noted that these are in fact new acquisitions for the
Leiden library from an extant collection.
A similar search should actually be repeated every ten years. In 2015,
certain authors, fields and types of research will be viewed differently.
In the decades to come, frequent systematic research in this enormous
collection will presumably yield more than hundreds of highlights from
the academic world.
I use the word dissertation here
as a generic term, also covering the German
Inauguraldissertation and Habilitationsschrift,
the French thèse and the Dutch proefschrift
and their predecessors, even though I am aware that these
terms have different meanings.
In the same way disputatio is not the only
word used to describe this phenomenon: alternatives include
dissertatio, excercitatio and thesis.
Olga Weijers: Begrip of tegenspraak?
Analyse van een middeleeuwse onderzoekmethode.
[Understanding or contradiction? Analysis
of a medieval research method] (Mededelingen KNAW, NR 65 no.
6, Amsterdam (2002)
I use the past tense since Dutch university
librarians decided at one of their joint meetings in 2004 to
terminate the exchange of Dutch dissertations in book form.
The automatic exchange with universities abroad had come to
an end in 1990, although some universities still send each
other lists of dissertations from which specific items can
be ordered on an exchange basis.
These enormous numbers and percentages are the more
remarkable since the various histories written about Leiden
University library – most recently Magna Commoditas
in 2001- largely ignore this collection of dissertations. In
this latest jubilee book the word dissertation is not
They are located in the closed repository of the
university library, cases 4334-4483 and 5178-5729.
On the website of Leiden University library you can find a
list of the cities (plus the periods covered) from which
uncatalogued dissertations are available: http://athena.leidenuniv.nl/ub/bc/index.php3?m=37&c=288
This assumption was made by R. Breugelmans (september 2004).
It is supported by, e.g., the inscription “Ex legato Wepferi”
in the Heidelberg disputation by Johannes Ott from 1670:
Cogitationes physico-mechanicae de natura visionis. The
1754 Paris dissertation by Chaupin (De partium externarum
generationi inservientium in mulieribus naturali, vitiosa et
morbosa dispositione, theses anatomico-chirurgicae)
contains an ex-libris of Corn. Henr. Â Roy, medicinae
Lars H. Breimer & D. Breimer: A computer-based
international ‘Thesis-Line’? In: Trends in biochemical
sciences, vol. 20 (1995), pp. 175-176.
Information from J. van Kooten Niekerk of Utrecht
University library (e-mail, 9 May 2003).
See the contribution by Joseph Freedman in hora_est! On
dissertations. Leiden, 2005.