The question of the morality of abortion has long been the subject of intense, sometimes acrimonious debate. Even people within the same religious or philosophical tradition often disagree on the issue. For example, there are Christians who are “pro- choice” and there are Christians who are “pro-life.” Both sides marshal biblical, theological, and philosophical arguments in support of their positions. The substance of the abortion debate seems to reduce to one tricky question: when does personhood begin? Christian experts in various (...) fields, such as theology, biblical studies, ethics, and philosophy, have protracted disagreements over this question. In this article we will apply insights from the current literature on epistemic peer disagreement to the abortion issue. We will assume that there is only one correct answer to the abortion question. However, after making a crucial distinction between rationality as understood by internalists versus externalists, we will argue that there is more than one rational answer to the abortion question, since there is more than one rational way to weight evidence. We will conclude that, in a case of disagreement between two Christians who are epistemic peers with regards to the morality of abortion, both parties can be rational in adhering to their respective positions, but that this does not entail or even support ethical relativism. (shrink)