Discourse Networks 1800/1900 erases the boundaries between the sciences. The book is broken up into two sections: 1800 and 1900. The first epistemic break around 1800 occurs when what you call the Republic of Scholars dissolves in the wake of standard alphabetization. Your periodization into Renaissance/Classical, Modern and roughly Postmodern corresponds in large to Foucault's division of European culture in The Order of Things. The end of the third of these periods coincides, as Foucault states, with the end of 'man' as the central figure of knowledge. Around 1900 the medium book's monopoly on the word is broken by new media such as the gramophone and film. The result is that language becomes perceptible as a medium. Mathematical formulas from Euler and Bolzano serve as epigraphs, or mathemes, to each section. How would you characterize these two equations?

(Kittler goes to the blackboard.) I had the following in mind: a sine curve can be derived from Euler's equation, that is, it's an equation for analog output; Bolzano's, on the other hand, is digital. I originally had mottoes from Borges and Castañeda, but I thought they were too poetic. So I hid myself behind the formulas. Euler's formula, which is actually more complex than the simple sine wave I've just described, was indeed a breakthrough in mathematics. Both equations appeared some seventy years prior to the discourse networks which they describe. Euler's formula is from 1735 and Bolzano's non-convergent sum is from 1830. I wanted to place both systems in the shadow of their mathematical do-ability. Euler had described functions of growth such as constant growth and compound interest which are in effect the organic models introduced by Goethe and Herder in their literature. How does something grow? How does an individual grow more independent, more intelligent, more free? Goethe's question, for example, in Wilhelm Meister is a question of compound interest. Around 1900, the discrete systems from Bolzano to Claude Shannon begin to appear. The model is almost too simple because it establishes a binary opposition between binary and non-binary. I think it could be made a little more complicated today. Everyone wants to know what the discourse network 2000 looks like. I'm not in such a hurry, besides it can't be written. I would be more interested in 1700 because one can't just leave it at the Republic of Scholars. Dissertations have been written here in the past few years which make it clear that the late Baroque, that is the age of Leibniz and Descartes, is not so simple as Foucault and myself have made it out to be. These figures are part of our present. The mathematics upon which the gramophone, film or radio are based come from this time period. I'd like to write a book about Descartes and modern geometry — from Descartes to computer graphics.