"Cogito ergo sum" - "I think, therefore I am": With this statement, Descartes established the rationalist thinking of the modern era. When Bruno Latour replaces the singular with the plural, he emphasizes that it is always collectives that think, and these collectives, according to Latour, also include inanimate objects and technology. The founder of political ecology supported this thesis in his groundbreaking interdisciplinary case studies on Pasteur's laboratory and the failed Paris public transport project Aramis. In Cogitamus, Latour illustrates his complex theory in fictional letters to a German student who mysteriously always misses his lectures.