van Zeebergh’s mind, but to no avail. On the contrary, relations subsequently seem to have hit
rock bottom, and van Marum quotes van Zeebergh as crying out “that if he had been able to
surmise that my plan had been to elevate the collections of Minerals in Teylers Museum to
such a (as he most improperly called it) colossal height, he should never have given his
permission to bring it together.” 113
Whatever way van Zeebergh might have told the story, the fact remains that van Marum
thereafter reduced his activities at Teylers Museum to a minimum - although he did remain its
director for many more years, until his death in 1837.
It is interesting to note that van Marum never severed his ties with the museum. Even after
1803 he continued to welcome important visitors for instance, such as the Emperor Napoleon
in 1811; he still oversaw the occasional acquisition for the museum’s collections; and above
all he continued to purchase books for the library — its premises were even expanded and it
was made more easily accessible to the general public in 1825.
Nevertheless van Marum’s main focus now was on botanical studies. To this end, he had
acquired a house with grounds which he christened “Plantlust” just outside the gates of
Haarlem, and began cultivating the plants he catalogued in 1810. As usual, he was not one to
do things by halves, and in this area too he corresponded with elite botanists from all over the
world, many of which — such as Joseph Banks — he had become acquainted with during his
previous travels. In 1816 he had an orangery built on his premises, and in 1817a hot-house.114
At the same time, van Marum was still the secretary of the Holland Society as well, and as
such became heavily involved in science policy at a national level, particularly during the
Napoleonic period and the establishment of the Dutch monarchy during the Restoration.
Even the politics however only had an indirect impact on the daily running of Teylers
Museum, certainly in the short term. What was far more important at this stage was van
Marum’s relative inactivity, which in turn meant that the collections he had built entered a
kind of “sleeping beauty” phase - they remained virtually unchanged for decades. And at the
same time, van Marum’s absence gave the kastelein more room to implement his own ideas
for the collection. This became all the more relevant when Wybrand Hendriks retired in 1819.
He was replaced by Gerrit Jan Michaelis, who took the fateful decision of purchasing
paintings - not just prints and drawings - for the museum. This paved the way for it to
gradually take the shape of a modem, public art museum.
Meanwhile, van Marum’s interest in botanical studies fit perfectly into his general approach
to the study of nature — to which we shall now turn.
11 “onverwachte verandering van denkwijze”; “dat indien hij had kunnen vermoeden dat mijn plan zoude
geweest zijn de verzamelingen van Delfstoffen, in Teijlers Museum tot zulk eene (zoals hij het zeer ongepast
noemde) colossal hoogte te verheffen hij nimmer tot derzelver aanleg, zijne toestemming zoude gegeven
hebben.” Martinus van Marum: “De Geschiedenis van de oprigting van Teyler’s Museum”, 1823-1833, Haarlem,
NHA, Archief van Marum, vol. 529, nr. 9, fol. 99-100.
114 For botanical activities see: M.J. van Steenis Kruseman, “Botany and Gardening,” vol. 3, Martinus van
Marum: Life & Work (Haarlem: Tjeenk Willink & Zoon, 1971), 127-174; Andreas Weber, Hybrid Ambitions:
Science, Governance, and Empire in the Career o f Caspar G.C. Reinwardt (1773-1854) (Leiden: Leiden
University Press, 2012), 98-100.
II Van Marum’s “Philosophy of Science”
1. He Kant be Serious
Van Marum, it seems, had little good to say about Immanuel Kant’s philosophy. So much at
least can be inferred from the transcription of a public lecture on mechanics van Marum gave
to a lay audience, in all likelihood consisting of more than 100 listeners, in 1796. As was his
habit, van Marum wrote out these lectures in their entirety. One can almost picture him
preparing this particular lecture, leafing through his German copy of Kant’s “Metaphysical
Foundations of Natural Science” which had been published some ten years earlier, and feeling
utterly stumped. Referring to one particular claim about attractive and repellent forces, van
Marum jotted down:
“It is utterly incomprehensible to me how a proposition that is so obviously in contradiction to
„ 1 1 5 what common sense so clearly teaches, can have found any advocates.
This, he then evidently decided, was perhaps a little too harshly worded, because he
subsequently struck out this passage. But the words that followed, although slightly more
diplomatic, were no less scathing, as he pondered:
“Whether Kant with all his cleverness really convinced himself by his ratiocinations of the
truth of this Proposition, has often seemed very doubtful to me.”
In other words, he considered all he read so incredulous that he doubted Kant himself actually
believed what he had written.
Van Marum’s statements are interesting for a number of reasons. Firstly, the fact that van
Marum devoted a considerable portion of his lecture to discussing - and deriding - this new
philosophy goes to show that Kant’s ideas were hotly debated in the Netherlands too, even
just a few years after their initial publication. Secondly, it might be reassuring to scholars
through the ages that Kant’s publications were considered both equally complex and puzzling
in their own time as they are by almost all subsequent students of Kant. Finally and most
importantly however, this episode reveals a lot about van Marum’s own views on knowledge,
and how one should approach the study of nature. More to the point, van Marum s rejection
of Kant’s arguments is not surprising if one realises that throughout his life, van Marum was a
strict adherent to the principles of empiricism, in the sense that he rejected any form of
speculation or any extensive body of theory that was not spawned by experimentation and
observation. In his eyes, even the mathematical formulation of theories could be more of a
hindrance than an aid. As he explained in his introductory remarks to another series of
lectures on physics which he gave before a different audience in 1779:
115 “Het is mij ten eenemaal onbegrijpelijk hoe eene stelling zo blijkbaar aanloopende tegens het geen het gezond
verstand zo duidelijke leert, nog eenige verdedigers kan gevonden hebben. ; below: Of de schrandere Kant door
zijne redeneering zich zelven waarlijk van deeze Stelling kan overtuigd hebben, is mij tneermaalen zeer
twijfelachtig voorgekomen.” “Openbare lessen in 1795 & 1796”, 12.12.1800, Haarlem, NHA, Archief van
Marum, vol. 529, nr. 12.