 Finally, Street challenges the realist to specify what faculty or capacity might ground our capacity to arrive at independent moral truths, how the former evolved, and how the latter could plausibly have arisen as a byproduct of it. She claims that there is no plausible story to be told here, since the capacity to grasp independent moral truths would have to be “a highly specialized, sophisticated capacity” akin to the human eye, and no such entity could plausibly emerge “as the purely incidental byproduct of some unrelated capacity that was selected for on other grounds entirely” (Street 2006, 142–43). But the realist’s story needn’t take that form. The claim will be just that our capacity to grasp moral truths—like our capacity to grasp philosophical truths about metaphysical necessity, say—is simply a byproduct of our general capacities for critical reasoning, combined with the evolved capacity for forming and employing normative concepts in our thinking and decision-making.