Abstract:Non-naturalistic moral realism holds a strong position on moral objectivity: it maintains that some of our moral judgments are true, and the moral facts that render these judgments true are independent of human stances or conceptions. This viewpoint aligns with everyday moral intuitions. However, critics like John Mackie argue that if moral realism holds, it becomes difficult to explain the widespread and profound moral disagreements observed in human life. This critique, known as the “argument from moral disagreement”, challenges moral realism based on the understanding of moral disagreement.In response, from the perspective of some moral realists, such as Russ Shafer-Landau and David Enoch, who uphold moral objectivity, contend that the argument from moral disagreement is difficult to sustain. They argue that the actual moral disagreements can be explained within the framework of moral realism: the factors shaping moral judgment are inherently complex, leading individuals to inevitably harbor cognitive biases and limitations—key drivers of such disagreements. From this perspective, moral disagreements arise due to cognitive deficiencies. Moral realists maintain that if humans had sufficient cognitive capacities and access to all relevant evidence, these moral disagreements would dissipate through cognitive advance. Anti-realists, however, counter that even under ideal cognitive conditions, moral disagreements remain conceivable and cannot be eliminated through cognitive advances. Yet, realists reject the possibility of such disagreements under ideal conditions, asserting that arguments from the ideal moral disagreements are inherently based on anti-realist assumptions. This, they argue, leads to the fallacy of “begging the question”. Besides, other arguments from moral disagreement rely on work in moral semantics or other fields, which are actually irrelevant to moral disagreement.By introducing the concept of “peer disagreement”, the question-begging issue of whether moral disagreements exist can be transformed into a question of understanding ideal moral disagreements. Peer disagreement refers to a situation where both parties have equal access to relevant evidence and are free from cognitive deficiencies. According to moral realism, moral disagreements should have rational resolutions. Evaluating these rational solutions requires a thorough understanding of how judgment differences arise. In the context of ideal moral disagreements, explanations offered by anti-realists appear more credible than those provided by realists. This suggests that it is more plausible to hold that moral realism cannot offer a realistic and rational resolution to peer disagreements. Unlike other fields commonly regarded as objective, morality presents a multitude of issues that remain subject to rational disagreements. This lends credence to the view that moral judgments are more plausibly explained by anti-realist theories—such as those emphasizing stances, emotions, and cultural influences—than by appeals to objective moral facts. Ultimately, the anti-realist position, which denies the existence of objective and independent moral facts, is comparatively more credible. In summary, compared to the meta-ethical framework of anti-realism, moral realists struggle to provide a convincing explanation for the emergence of ideal moral disagreements. This places a heavier burden of justification on moral realism in addressing the issue of moral disagreement.Moral disagreement is a significant moral phenomenon a moral theory that cannot adequately account for the pervasive and profound moral disagreements is hardly plausible. The argument from moral disagreement presented here, framed through the lens of peer disagreement, avoids the fallacy of begging the question. Simultaneously, it offers a critical challenge to moral realism by focusing on the very phenomenon of moral disagreement.
庄玄朴. 何种道德分歧论证会对道德实在论构成挑战?[J]. 浙江大学学报(人文社会科学版), 2025, 55(12): 76-88.
Zhuang Xuanpu. Which Form of the Argument from Moral Disagreement Could Pose a Challenge to Moral Realism. JOURNAL OF ZHEJIANG UNIVERSITY, 2025, 55(12): 76-88.
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