Historicists suggest that the historical record of scientific inquiry itself give us reasons to doubt the truth of even the best contemporary scientific theories. One recent line of thought holds that the most compelling version of such an historicist challenge is posed by a particular pattern in that record: our repeated failure to exhaust the space of theoretical alternatives well-confirmed by the evidence available to us at a given time. Scientific realists have suggested in reply, however, that the failure to recognize such “unconceived alternatives” might be more plausibly attributed to past scientific communities than to those of the present day. I will first argue that this response is rendered unconvincing by what historians of science already recognize as the most profound transformations of the organization and structure of scientific inquiry since the Scientific Revolution. I then go on to suggest, however, that confronting this question invites us to reconceive what really divides the two sides of a realism dispute genuinely worth having, in large part because the answer we give to it carries significant consequences for how we should actually go about conducting the scientific enterprise itself.