 As the preceding sections should have made clear, there is ample evidence that biological research does not fit a Popperian image of science according to which “The theoretician puts certain definite questions to the experimenter, and the latter, by his experiments, tries to elicit a decisive answer to these questions, and to no others. All other questions he tries hard to exclude” (Popper 1959, 107). According to Rheinberger, much experimental research in biology does not aim at testing pre-conceived theories. However, sometimes theories or theoretical frameworks are, in fact, adopted by the scientific community, while others are abandoned. Even if it is true that most research is not aimed at testing theories, research can still undermine some theoretical ideas and support others, to the point that one framework is chosen while another is rejected. How are such choices made? What principles guide them? And do the choices actually exhibit some kind of epistemic rationality, as most philosophers of science think, or do they merely reflect the interests or larger cultural changes in society, as many sociologists and historians of science think?