Postscriptum**

Abstract

Lara Keuck and Kärin Nickelsen, the organizers of this special issue and its workshop, invited me to contribute a closing commentary, and I feel honored and pleased to do so. Now that the English version of the book that inspired it is forthcoming,¹ it might be better to look ahead instead of looking back. Therefore, I will try to convey in my concluding remarks less the air of a closure than that of an outlook on things to come. And I hope I will be forgiven the rather rhapsodic character of what follows.

I will organize my remarks along the three sections of the issue, Conjunctures, Traces, and Fragments, before concluding with a brief note on historical epistemology. But first, let me comment on the title of my new book: Spalt und Fuge, in English, Split and Splice. The title was chosen with deliberation. Spalten, to split, and fügen, to splice, are the two cardinal activities of experimentation. I consciously avoid the traditional notions of analysis and of synthesis. They are logical categories that have been imported into the practice of experimentation; they have not grown out of it, and they suggest neat divisions and equally neat fusions. Neither is characteristic of the experiment. Experimentation, as a process of finding one's way into the unknown, needs more practice-oriented categories in order to apprehend its moves. If you split a log, the wood resists, and the products of your wedging activity will show uneven faces, depending on the knots and inner structure of the trunk. The same holds true for the object of your experimental inquiry; knowledge of these structures is of utmost importance for experimental exploration. If you splice a rope or if you graft a twig onto your vine, the points of suture will remain visible as signs of a mutilation. So will the pieces of your experimental activity, if joined to form a whole again. And it is indeed of utmost epistemic importance for the ongoing experimental process not to forget that these sutures always are—and will have to be—provisional. The title of this phenomenology of experimentation, Split and Splice, aims at calling to mind these epistemic uncertainties, inherent in the life of epistemic things.