The early history of the three large National Museums in Leiden, the Netherlands, is characterized by Enlightenment principles such as education, instruction and foremost rationalism. However, it would be a mistake to think that the history of these museums can be adequately described by referring to enlightened, rationalist ideas only. Partly as a reaction on enlightened rationalism the Romantic movement developed at the end of the eighteenth century. It is argued that the nineteenth century history of the three large national museums in Leiden can best be understood as a process influenced both by reason and structure as well as by irrationality and ‘the absence of structure’. It is most likely that modern museum practices are also influe...