 In the 17th century, observation and experiment were seen as “an inseparable pair” (Daston 2011, 82) and by the 19th century they were understood to be essentially opposed, with the observer increasingly seen as passive and thus epistemically inferior to the experimenter. In fact, already Leibniz anticipated this view stating that “[t]here are certain experiments that would be better called observations, in which one considers rather than produces the work” (Daston 2011, 86). This aspect of the distinction has been a mainstay of understanding scientific practice ever since.